1 CHAPTER 01 INTRODUCTION TO ANATOMY and PHYSIOLOGY ANATOMY & PHYSIOLOGY I
Anatomy and Physiology I Anatomy
Transcript of Anatomy and Physiology I Anatomy
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Dr. Linda Adamcheck FTZ 339
Anatomy and Physiology I
Anatomy: Study of internal and external structures of an organism and the relationship between
those structures.
1. Microscopic anatomy : cannot see with the naked eye
a. Cytology: study of internal cell structures
b. Histology: study of tissue
i. Tissue (def) groups of similar cells that perform a common function
2. Gross anatomy: visible structures
a. Surface anatomy – study of general form and superficial markings of an organism.
b. Regional anatomy (med school type) –study of all structures in an area in detail.
c. Systemic anatomy – study of structures of an organ system.
i. Organ system (def) 2 or more organs working together to perform a
common function.
Physiology – Study of the functions of an organism.
1. Cell physiology – chemical and molecular processes that take place inside the cells.
2. Systemic physiology – function of organ systems
3. Pathophysiology – study of the effects of disease on an organ system.
Levels of Organization (simple to complex)
1. Chemical or Molecular – forms organelles; functioning units in the cells.
2. Cellular – smallest living unit within the body
3. Tissue – group of similar cells performing common functions
4. Organ – 2 or more tissue types working together to perform a common function
5. Organ system – 2 or more organs working together to perform a common function or functions.
6. Organism – all of the organ systems in the body working together to maintain life. (Level highest
for humans).
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Organ Systems
System Major Function 1 IInntteegguummeennttaarryy
SSyysstteemm Protection (skin), surface receptors, Vit D synthesis,
Sweat & oil glands
2 SSkkeelleettaall SSyysstteemm Protection, support, blood cell formation, stores minerals (calcium)
3 MMuussccuullaarr SSyysstteemm Movement (Locomotion) & Expression #1 Function, support (posture), Heat production.
4 NNeerrvvoouuss SSyysstteemm #1 Perception of Stimuli, #2 Immediate response to stimuli, Coordination
Of other systems. (runs the show)
5 EEnnddooccrriinnee SSyysstteemm Long Term Changes (regulation of) in activities of other organs through chemical messages called hormones.
6 CCaarrddiioovvaassccuullaarr
SSyysstteemm TRANSPORT of blood cells & dissolved materials like
nutrients, wastes, and gasses
7 LLyymmpphhaattiicc
SSyysstteemm Involved in immunity – defense against infection and
disease. Houses most of our WBCs, also helps regulate fluid volume.
8 RReessppiirraattoorryy
SSyysstteemm Delivers gas to exchange surfaces between lung and
blood
9 DDiiggeessttiivvee SSyysstteemm Processes food and absorbs the resultant nutrients, minerals, vitamins, and water into blood.
10 UUrriinnaarryy SSyysstteemm Elimination of excess H2O, salts and wastes, especially Nitrogen waste (UREA)
11 RReepprroodduuccttiivvee
SSyysstteemm Mainly : Produces sex cells (egg & sperm) secondary:
produces hormones
Homeostasis – Refers to maintaining a constant internal environment without regard to
the external environmental conditions. USES LOTS OF ENERGY
Regulated 2 ways:
1. Negative feedback (99% done this way) – some change to homeostasis is perceived by the body
as negative, or not good, The body initiates a process to reverse that change. [there is an
acceptable range of deviation]
a. An example would be body temperature (body causes sweat and vasodilatation)
2. Positive feedback – There is a change in homeostasis, the body sees this as a positive or
necessary change and institutes mechanisms or changes to take you further away from
homeostasis.
a. An example is Uterine contractions (child birth), body produces Oxytocin
b. Another example is blood clotting to heal cuts.
c. Positive Feedback is episodic
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Language of Anatomy 1/17/08
Anatomical Position : Upright posture with palms facing forward.
Anterior (ventral)=toward the front of the body (in front of)
Posterior (dorsal)=toward the back of the body (behind)
Superior (cranial)=toward the head or upper part of the body (above)
Inferior (caudal)=away from the head or toward the lower part of the body (below)
Medial=toward or at the midline of the body or inner surface of an extremity
Lateral=away from the midline or the outer surface of an extremity
Proximal=Close to the origin of the body part or the point of attachment of a limb
Distal=Further away from the attachment point of an extremity
Superficial=toward or at the body surface
Deep=away from the body surface; more internal
Regional :
Appendicular= Limbs and Girdles that hold the limbs to the trunk.
Girdles
Pectoral girdle – holds arms
Pelvic girdle – holds lower extremities
Sagital Plane – Divides the body into right and left parts:
Mid Sagital plane = directly through the center of the body : equal sides
Para Sagital plane = divides the body into unequal right and left sides
Must use a reference point (nipple, etc.)
Frontal or Coronal plant – divides a specimen into anterior and posterior sections
Transverse or horizontal planes – divides a body into a superior and inferior sections
Body Cavities
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Serous membranes: thin, clear, shiny, wet membranes that wall off pleural and pericardial cavities
Parietal pleura (OUTER) : membrane that walls of the pleural cavity
Visceral pleura (INNER): membrane that walls off the pleural cavity and is attached to the
surface of the lung.
Parietal pericardium (OUTER) membrane that walls off and is attached to the surface of the
pericardium cavity
Visceral pericardium (INNER) membrane that walls off and is attached to the surface of the
pericardium
Axial portion of the body – 2 Major cavities or spaces
Anterior or Ventral Cavity
Dorsal or posterior Cavity
a. Cranial Cavity (smaller)
b. Spinal Cavity
Thorasic Cavity (superior) located from the 1st rib down to the diaphragm
a. Right Pleural Cavity
b. Left Pleural Cavity
c. Pericardial Cavity (heart)
d. Mediastinum – area of exclusion: area in the thoracic cavity that does
not contain the things NOT in the Pleural or Pericardial cavities
Abdominal Pelvic Cavity – Below Diaphragm
Peritoneum: serous membrane of the abdominal pelvic cavity
Parietal peritoneum – outer serous membrane
Visceral peritoneum – inner serous membrane that covers each organ
Retro Peritoneal Space – Behind, not enclosed space behind the peritoneum
Contains the Kidneys, Adrenals, Pancreas, a little of the small and large intestine.
Quadrants centered on the umbilicus
-mid saggital plane from breastbone to pubic bone
-transverse plane through navel
RUQ – Liver & Gallbladder
RLQ – Cecum (first part of large intestine), Appendix (on cecum)
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CHAPTER 2
Definitions:
a. Matter: anything that takes up space
b. Element – a unique substance that cannot be broken down any further by ordinary means
c. Atom – building block of elements – have sub-atomic particles
a. Proton (+)
b. Neutrons (no charge)
c. Electrons (-) : orbit the nucleus of the atom
i. 1st orbital (lower) has 2 or less electrons
ii. 2nd orbital and above have a max of 8 electrons
Chemical reactions are driven by the number of electrons in the Atom’s outer shell.
Ion: charged atom
Cat ions (positive charged Ions)
Anions (negative charged ions)
Carbon Atoms 6 Protons, 6 Electrons, 6 Neutrons
Definition: Molecule – combination of two or more atoms.
Patterns of Chemical Reactions.
Synthesis reaction: A + B = C A and B are smaller than C
Anabolism – sum of all the synthesis reactions in your body
Decomposition reaction: C = A and B (breakdown)
Catabolism – all the decomposition reactions in your body
Metabolism: Sum of all Catabolic and Anabolic reactions in the body.
PH: measures how acidic or alkaline a substance is.
Ph 7 is Neutral
Definitions:
ACID – something that gives up hydrogen ions.
Stomach acid Ph 1.5 – 2.0
BASE – something that can accept hydrogen ions
Human blood Ph 7.4
1. INORGANIC COMPOUNDS = compounds that do NOT contain carbon, except CO and CO2
a. Water H+-OH- (H2O) Ph=7 can give or take a hydrogen ion.
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i. Oxygen does not share electrons well which creates a slightly pos charge on the
Hydrogen side and a slightly neg charge on the opposite side. The water
molecules then have a weak attraction called a hydrogen bond that holds water
molecules together.
ii. Functions of water:
1. Stabilizes our body temperature
2. Protects us as a cushion and as a lubricant
3. All chemical reactions in the body take place in water (metabolism)
4. Solvent – dissolves solute – solution (eg. H2O +NaCl – solution saline)
2. ORGANIC MOLECULES – Contain Carbon, except CO and CO2
a. Carbohydrates
i. Contain carbon, oxygen and hydrogen.
ii. For every carbon and oxygen there are 2 hydrogens
iii. Building blocks of carbohydrates are monosaccharides
1. 5 and 6 carbons long
2. Example: ribose and deoxyribose - 5 carbons long
3. Example: Glucose and Fructose - 6 carbons > combined = sucrose
(sugar)
Monosaccharide Galactose plus Glucose = disaccharide Maltose
Any more than two are called polysaccharides (long chains of monosaccharides strung
together)
** polyglycogen – way we store carbohydrates – mostly glucose units.
Plants store carbs as starch (cellulose in plant cell walls)
iv. Functions of carbohydrates:
1. Structural components – building blocks for certain molecules.
2. #1 choice as an energy source (monosaccharide)
a. Di and polys need to be broken down first
3. Bulk – insoluble carbohydrates absorb water.
b. Lipids - Structure - Ratio of Oxygen is very low in lipids compared to carbohydrates.
Less polar or less charged and therefore they don’t dissolve in water.
i. Fatty Acids - Building blocks of lipids (12 – 20 carbons long)
1. Saturated fats have NO double bonds and are harder to break down
2. Non-saturated fats have at least one double bond between carbons
a. They are easier to break down
b. Trans-fats are artificially created double bond fatty acids and
cause cancer
ii. Glycerides
1. Glycerol (alcohol) You can attach a Glycerol to a Fatty Acid. One
molecule of Glycerol and One Fatty acid attached to it is a mono-
glyceride.
a. 2 = diglyceride
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b. 3 = triglyceride ** One glycerol and three fatty acid - this is the
way you store fat in your fat cells.
iii. Phospholipids
1. Di-glyceride (glycerol with two fatty acids) with a phosphate group and
something else on the water loving head.
2. Glycolipids : similar but with carbohydrates on the di-glyceride
iv. Steroids : not very polar and therefore does not like water
1. Ring structure of rings of fatty acids
a. Examples
i. Cholesterol – steroid type of lipid
ii. Bile salts (produced in liver and stored in gallbladder.
This is an emulsifier (helps fat get more soluble in
water)
iii. Sex hormones : estrogen and testosterone : building
blocks are fatty acids.
v. Vitamins Fat dissolving vitamins A, D, E & K lipid in nature : Cofactors for
some processes
1. A: vision
2. D: bone growth
3. E: Anti-oxidant (ties up free oxygen radicals)
4. K: clotting factor
vi. Functions of Lipids
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1. Protection
2. Insulation
a. Thermal
b. Electrical
i. Myelin – fat based compound on the outside of nerves
that is like wire insulation.
3. Regulation
a. Steroid hormones regulate processes
4. Structure – all our cells have membranes made up of phospholipids
5. Energy source (#2 choice)
c. PROTIENS – carbon, hydrogen + oxygen +nitrogen (sets them apart)
i. Huge molecules
ii. Building blocks – amino acids (there are 20 different amino acids)
iii. Two – dipeptide, three – tripeptide,
iv. Protien – polypeptide start at about 10 amino acids and up to about 10,000
v. PROTIENS WORK BASED ON THEIR SHAPE
vi. ** The order that the amino acids are in is called the primary structure of that
protein.
vii. Twisting like a helix or bending in parts is the secondary structure.
viii. If the amino acid folds back on itself it can form into a Globular or tertiary
structure.
1. Tertiary structure is achieved when alpha helix or beta pleated regions
of the polypeptide chain fold upon one another to produce a compact
ball-like, or globular molecule.
ix. If two or more proteins are together it becomes the 4th or quaternary structure.
1. Hemoglobin is a 4 globular proteins together.
x. PROTIEN FUNCTIONS
1. Regulation
a. Hormone proteins
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b. Enzyme protein (catalyze protein)
2. Transport (hemoglobin)
a. Also in cell membrane that transmits across the membrane
3. Protection (antibodies)
4. Contraction
a. Actin and myosin (in muscle cells)
5. Structure (hair, nails, outside layer of skin, etc.)
a. Tendon (muscle to bone)
b. Ligument (bone to bone)
6. Energy source – last choice for energy.
d. Nucleic Acids – organic molecule C+ H + O + N + P (phosphores)
i. Largest molecules in our body
ii. DNA and RNA
1. ***Building blocks of nucleic acids are nucleotides.
Phosphate/Ribo-sugar/nitrogenous base
Phosphate and Sugar are the rails of DNA
Every three base pairs of DNA is the recipe for an amino acid, and therefore proteins.
ENERGY COMPOUNDS
1. ATP Adenosine Tri-Phosphate
a. One base is called ADENINE and is attached to a RIBOSE SUGAR the attached to
phosphate groups (phosphate with 4 oxygens).
b. Recycling molecule. Stores energy in the oxygen bonds holding the phosphate
groups together.
c. Cleaving off the third group leaves ADP (ADENINE DI-Phosphate)
d. Cleaving off the second group leaves AMP (Adenine mono-phosphate)
e. Each successive energy release is lower
f. Cyanide stops ATP formation / Arsenic is an ATP imposter
CELLS 1/31/08
Cells are the structural and functional unit of the body
Divided into Intracellular and extracellular
The cell membrane determines what passes into and out of the cell.
A. Membrane Structure (the fluid mosaic model)
a. Membrane lipids (made of fatty acids, therefore non-charged region
i. Phospholipids
ii. Cholesterol – structure of cell wall (steroid lipid)
1. Stabilizes phospholipids but still allows flexability
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b. Membrane proteins page 69
i. Integral proteins – go entirely through the cell membrane
ii. Peripheral proteins – go partway through the cell membrane
iii. Some have carbohydrate chains on the extracellular side, ALL OF THE
CARBOHYDRATES OF THE CELL TOGETHER ARE CALLED GLYCOCALYX
1. Their function is to lubricate the outside of the cell (protection function)
2. Glycolipid : when carbohydrates are on the phospholipid
iv. FUNCTIONS of MEMBRANE PROTIES
1. Channel Proteins : can help polar substances through the membrane
2. Some of the cell membrane proteins are enzymes that catalyze
processes of the cell.
3. Receptors – all hormones have to bind to receptors.
4. Intercellular joining (cell junctions) – intergral proteins fuse with each
other
5. Cell-Cell recognition : Glycoprotein (proteins bonded with sugar chains)
serve as identification tags – recognized by cells (like white cells)
6. Attachment to cytoskeleton (structure inside cell) – proteins attach it to
the walls
v. Cell membranes are not-rigid – have the consistency of olive oil – they have
flexibility and move around (non-static)
c. Membrane projections page 70,93,94
i. Microvilli – minute finger like projections like extensions or projections of the
cell membrane.
1. Function: increase surface area of the cell to provide faster diffusion
2. They don’t move
ii. Cillium – much longer than microvilli
1. Constructed with 9 pairs of protein tubes and 2 in the middle (9+2)
2. Found mostly in the respiratory system, moves mucus and uses ATP
3. Moves in one direction
iii. Flagellum – ONLY in one place (sperm cell)
1. Much longer than cilium
2. Can be used back and forth – propels the cell
d. Membrane Transport
i. Permeability
ii. 2 major groups of processes - ACTIVE and PASSIVE transport (in general passive
transport does NOT require ATP
1. Passive Process
a. Diffusion – Tendency of molecules to move from an area of
higher concentration to an area of lower concentration
i. The molecule that diffusion is following is concentration
gradient from high to low
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ii. Lipid soluble diffuse through the membrane (oxygen,
alcohol)
iii. NON Lipid solute – go through proteins
b. Osmosis – movement of water through a membrane from area
of greater concentration of water to an area of lesser
concentration.
c. Facilitative diffusion – uses a non-channel protein to help
substances diffuse through the membrane by changing the
protein’s shape. (proteins work by their shape)
i. Molecule binds to protein, protein changes shape, then
the molecule is released into the cell
1. Specific shape : molecule will only go from area
of higher concentration to low concentration
(along the concentration gradient) example is
glucose, ions, amino acids
2. Rate of diffusion is based on the number of
transport proteins for that substance.
d. Filtration – passive process NOT run by concentration gradient.
i. Run by a pressure gradient
ii. Things want to move from higher pressure area to
lower pressure area
iii. Kidney works by filtration
2. Active Process (Carrier Mediated Transport)
a. Active transport – membrane proteins use ATP to move
substances across a membrane: used because:
i. To move something AGAINST its concentration gradient
ii. To move WITH its concentration gradient but FASTER
b. Vesicle – Membrane bound bubble
i. Endocytosos : the membrane wraps around something
extracellular and takes it into the cell.
1. Pinoctosis : liquid
2. Phagocytosis: solids
ii. Exocytosis: the vesicle (membrane) wraps around
something intracellular and takes it out. It fuses with
the cell wall and releases it outside the cell.
Definition: Co-Transport: taking two substances from one side of the cell membrane and
transporting them to the other side of the membrane.
Counter-Transport: swapping two substances across the membrane. Both
substances have to attach before they will move. (sodium-potassium pump)
If you use ATP with this transport, it becomes active transport.
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CYTOPLASM - That material inside the cell that is between the cell membrane and the nucleous.
1. Cytosol: mostly water with dissolved ions (charged atoms), small proteins and building
blocks of other organic molecules.
a. Small proteins are sometimes enzymes and therefore a lot of reactions occur (Rx)
2. Organelle: tiny specialized structure inside the cell. Each of these organelles will perform its
own function. TWO MAJOR GROUPS OF ORGANELLES: Membranous and Non-Membranous
a. Number and type of organelles inside the cell are dependant on what the job is.
b. Mitochondria: Rodlike double-membrane structure, inner membrane folded into
projections called cristae. HAS ITS OWN DNA and divides like bacteria
i. Site of ATP synthesis.
ii. 1 Molecule of glucose is converted into pyruvic acid and 2 molecules of ATP
during the anaerobic stage, then with oxygen (aerobic stage), 34 ATP
molecules are produced.
c. Ribosomes: Dense particles consisting of two subunits, each composed of ribosomal
RNA and protein; can be free or fixed to the rough endoplasmic reticulum.
i. Rough ER Endoplasmic reticulum, if it has ribosomes on it
ii. Smooth ER Endoplasmic reticulum if it does not have ribosomes.
d. Endoplasmic reticulum: membrane system. Makes a pathway and connects the
membrane to the nucleus. (like a subway to the nucleus).
i. Functions
1. Rough ER produces proteins for export, can synthesize
phospholipids and cholesterol.
2. Smooth ER site of other lipids including steroids. ALSO does
detoxification and functions as a storage area.
e. Golgi Apparatus: stack of smooth membrane sacs
i. Function
1. Packages, modifies, segregates proteins for secretion from the cells.
It can put these products into vesicles (this is the site of vesicle
production inside the cell.)
f. Lysosomes: membranous vesicle sacs made by golgi apparatus that contain acid
hydrolysis (breakdown enzyme)
i. Function
1. Site of intercellular digestion
g. Peroxisomes: Membranous sacs of oxidase enzymes; HELP WITH DETOXIFICATION
h. Microtubules: cylindrical structures made of protein
i. These form another organelle called Centiole
ii. Support the cell and give it shape.
i. Microfiliments: made from proteins that are involved with contraction (Actin,
myosin)
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i. Involved in muscle contraction and other types of intracellular movement.
This helps form the cell’s cytoskeleton, cilia and flagella if present.
j. Centrioles: paired cylinderacle bodies composed of 9 triplets of microtubules.
i. Function
1. During cell division, they go to opposite sides of the cell and form
spindles. This establishes where the cell is going to divide.
k. Cytoskeleton: made of tubular proteins (microtubes and microfilaments)
i. Definition – A framework for the inside of the cell, utilized to attach things
to.
ii. Anchored to proteins in the cell wall
iii. Extensions of the cytoskeleton become microvilli and cilia
3. Nucleus
a. Surrounded by nuclear envelope {a double membrane structure}
i. The outer membrane is part of the endoplasmic reticulum
ii. Has discreet pores (steroid hormones go right through the membrane)
b. Fluid portion – neucleoplasm
c. Solid center – nucleoli
d. Rest of solid material – chromatin
e. Information comes out of the nucleus as messenger RNA
f. Nucleoli (us) are solid non membrane bound and made from Ribosomal RNA
i. Makes Ribosomes
g. Cromatin – DNA proteins called histones
i. When the cell is ready to divide, the DNA wraps around the histones, then
coils up and then coils around itself into a SUPERCOILED DNA this is called a
Chromasome
h. GENERAL FUNCTIONS of the Nucleus
i. Control center of the Cell
ii. Place where ribosomes are made
iii. Transmits genetic information
iv. Provides the instruction for protein synthesis
HYSTOLOGY -Tissue
4 BASIC TYPES OF TISSUE
1. Epithelial Tissue : covers surfaces and lines cavities
2. Connective Tissue:
a. Fills up spaces
b. Provides structural support
c. Transports materials
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d. Stores energy
3. Muscle Tissue
a. Movement
b. Heat
4. Nervous Tissue – carry information to destinations in the body through electro-chemical
impulses.
A. Epithelial Tissue
a. Characteristics
i. Cellularity – composed almost entirely of cells. Only a little bit of non-living
material in the basement membrane (cellular glue)
ii. Polarity – 2 distinct surfaces
1. Apical surface – free edge
2. Basal surface – that side that is attached to the body
iii. Attachment to other cells – cell junctions
iv. Avascularity – not attached to blood vessels
1. Usually not very thick – nutrition by diffusion
v. Regeneration – high capacity to regenerate
b. Functions
i. Protection – need multiple layers (outside layers dead)
ii. Control permeability – any substance that enters or leaves your body has to
pass through epithelial cells.
iii. Providing sensation – nerve receptors grow into it.
iv. Produce secretions – layer the inside of the gland that makes the product.
c. Cell Junctions
i. Tight junctions = integrated proteins fuse on the walls of two cells together
(stomach wall)
ii. Gap Junctions = fusion of channel proteins between cells – provides a direct
connection between two cells for rapid movement. (Cardiac muscle cells –
spread ions very quickly from cell to cell)
iii. Desmones (like spot welds) = button-like plaques that are attached on one side
to the cytoskeleton on the inside of the cell and on the other side to another
desmone using “linker” proteins. (skeletal muscles). Tight but scattered.
d. Classification : shape of cell and # of cell layers
i. Flat cells : squamous
ii. Tall cells: columnar
iii. Squarelike cells: cuboidal cells
iv. One cell layer is called simple
v. Two or more layers is called stratified.
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Cell classifications that we will be studying:
Ciliated pseudostratified columnar cells (Trachea)
Nuclei all over the place, Some are goblet cells (make mucus)
Simple squamous (LUNG)
Simple cuboidal (Kidney)
Simple columnar (Stomach)
Stratified squamous (Skin)
Transitional epithiliam (Ureters, ability to expand and contract, they get thick and thin)
2/12/08
1. Simple Squmous Epithelium – single layer Flat cells
i. Lines ventral body cavities
ii. Alveoli of lungs
iii. Thinnest tissue in the body (allows fast diffusion)
iv. Lines inside chambers of heart and vessels
b. Functions
i. Reduces friction (when wet) – makes serous fluid
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ii. Performs absorbtion
2. Stratified squamous epithelium – multi layer flat cells
a. Location
i. Skin
ii. Mouth, throat, esophagus, rectum, anis, vagina
b. Function
i. #1 – Provide physical protection against abrasion, friction
ii. Protection against pathogens, chemicals, etc.
iii. Keeps water in
3. Simple Cuboidal epithelium – single layer equal sided cell
a. Location
i. Found in all glands (kidney)
ii. LARGE nuclei in the cell
iii. The apical edge is the outside edge
iv. The basement membrane is attached with non-cellular glue like substance
b. Function
i. Secretion (glands secrete)
ii. Minor absorption
4. Simple columnar epithelium
a. Location
i. Stomach, small and large intestines, gallbladder and ureters
ii. Some are modified and called goblet cells (they produce mucus)
iii. Have microvilli for absorption
b. Function
i. #1 – absorption (clue is the microvilli)
ii. Secretion (mucus), protection
5. Ciliated pseudo stratified columnar epithelium – looks like multi layer but it is not
a. Location
i. Nasal cavity, bronchi & trachea (cilia is the clue)
ii. All columnar epithelium have goblet cells (mucus production)
b. Function
i. Protection and secretion
6. Transitional epithelium
a. Does not fit in other categories
b. Found in urinary bladder lining
c. These cells look like multi layer cuboidal
d. When the bladder is expanded they look like sqamish
e. Function: allows bladder to expand and contract
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GLANDS
TWO GROUPS Endocrine and Exocrine Glands (the majority are exocrine)
Differences:
Exocrine glands secrete their product into a tube
Endocrine glands secrete their product into extracellular fluid.
They do this so it can be picked up by the blood
They usually secrete hormones
MODES OF SECRETION Merocrine, Apocrine, and Holocrine (MAH)
Merocrine: only secretes the product, uses exocytose. (cells produce product and release in
vesicles.
Apocrine: Some of the cell is secreted with the product (mammary glands), cell repairs itself
Holocrine: The cell lyces – cell and product secreted
Cell division replaces cells
Oil glands in skin
CONNECTIVE TISSUE General Functions
1. Fill up spaces
2. Protect
3. Support
4. Store Energy
5. Heat
Consists of Cells and the Matrix (cells are living, matrix is non-living)
MATRIX
-------Fibers and or ground substance
a. Protein fibers (three types) Collagen, Elastin and Reticular
1. Collagen Fibers – most common protein in the body
a. Microscopically looks like rope (function follows form)
i. Flexible, strong along long axis, NOT ELASTIC, imparts those qualities to the
tissues they are in
2. Elastin Fibers
a. Terciary, flexible, some strength, elastic
3. Reticular Fibers
a. Very fine, very thin collagen fibers
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b. Branch with each other (branched network)
c. Use them as a strainer (filter things)
i. Spleen is almost all reticular fibers
d. Support other things (support WBCs in certain tissue)
4. GROUND SUBSTANCE
a. Varies in consistency from a fluid to a semi-solid (example – blood (fluid) and
cartilage (semi-solid))
Made of 1. Proteoglycans and 2. Hyaluronic Acid
1. Proteoglycans (absorb water) can be a constituent of ground substance
a. Gives the tissue the quality of resilience
i. Discs between vertebrae
2. Hyaluronic Acid: very slippery, like Teflon
a. Found in joints.
CELLS – the living material
In most cases the cells are secreting the matrix
Suffex definitions:
-blast – actively secreting matrix
-clast – actively breaking down matrix
-cyte – maintaining the matrix
Classifying connective tissue is done by:
1. Type and amount of matrix
2. Type of cells
Four major categories of connective tissue
Connective Tissue proper
Cartilege
Bone
Blood (liquid matrix)
2/24/08
Connective Tissue Derived From:
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1. Fibroblasts
a. Connective tissue proper. Two categories Loose and Dense
b. Loose connective tissue proper:
i. Areolar Connective Tissue
1. Thin, Gel like matrix
2. All 3 fibers are present
3. Has white blood cells in it.
4. Adipocytes (fat cells, another kind of connective tissue
a. Functions:
i. Wraps and cushions organs
ii. Attaches skin onto the rest of the body (hypodermis)
iii. Underneath other epithelium
ii. Adipose Cells (Fat) – Large open looking cells
1. Not a lot of fibers
2. Each cell contains a drop of Triglyceride (Matrix of adipose)
a. Does not secrete the matrix itself.
3. The nucleus is pushed to one side of the cell by the Triglyceride
4. Kinds of fat:
a. White Fat – will become yellow as you get older.
b. Brown Fat – Only in infants and very young children
i. Between the shoulder blades and around the neck
ii. Looks brown because they have a lot of mitochondria +
high blood supply.
1. Function: For head production
5. Functions of adipose connective tissue
a. Stores fuel
b. Insulation
c. Helps to support and protect the organs
d. Location: found in the hypodermis (along with aeolar tissue
e. BIG cells found around organs.
iii. Reticular loose connective tissue
1. Short black fibers and the cells that secreted them are attached. These
cells are reticulocytes
2. Found in spleen (filters), in Lymph nodes and as the framework for bone
marrow.
3. Functions:
a. Filter in spleen and lymphnode
b. In bone: framework for blood cell formation (marrow)
c. DENSE CONNECTIVE TiSSUE 2 types : Dense Regular and Dense Iregular
i. Dense regular – parallel bunches of collagen fibers tightly packed together.
1. - Fibers that are more closely packed together.
2. In between are the fiberblasts that secreted that material
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3. Found in tendons (muscle to bone) and Ligaments (bone to bone)
4. Hard to heal because it is less vascular
5. Functions
a. Provide firm attachment
b. Conduct the pull of the muscles
c. Stabilizes the relative position of bones
ii. Dense irregular
1. Has irregularly arranged collagen fibers and elastin fibers (made by a
fibroblast)
2. Identification done by exclusion – looks like a mess
3. Found in the dermis (layer 2) under the stratified squamous epithelium
a. Capsule of visceral organs
b. Nerve sheaths (muscle)
4. Functions:
a. Provides strength to resist forces applied from many directions
b. Helps prevent overexpansion.
2. Chondroblasts – cells that make cartilage
a. Cartilage: ground substance – firm gel, fibers run through
b. Cells secrete gel and fibers, surrounding itself, then they stay there. Leaves a hole
where the cell lives. The hold is called a Lacuna.
c. Cells holes identify cartilage, then look at the ground substance to identify the type.
ID Cartilage:
1. Cells living in holes?
2. Fibers in the ground substance?
a. No = hyaline cartilage – tough, flexible, reduces friction
i. Found covering bones in joints, trachea, nose
ii. Most of the skeleton was hyaline cartilage before it was
bone.
3. Function: provides stiff but flexible support, reduces friction between
surfaces.
d. TYPES:
i. Elastic Cartilage
1. Cells living in holes
2. Short black fibers
3. Found in pinna of ear (external), epiglottis, and auditory canal
4. Function:
a. Gives support but tolerates distortion without damage
5. VERY LITTLE circulation in cartilage
ii. Fibro Cartilage
1. Cells living in holes
2. Densly packed bunches of collagen
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3. Fibers in matrix
4. Function
a. Very strong
b. Resists compression
c. Prevents bone to bone contact
d. Limits relative movement
5. Meniscus – a wedge like piece of fibro-cartilate in knee, holding the
bone in place found in pubic synthesis
3. Osteoblast Cells - Compact bone and spungy bone.
a. Matrix of bone – has organic and inorganic componants
i. Organic component: collagen fibers
ii. Inorganic component: calcium phosphate salts (hydroxyapatite)
iii. Strong and somewhat flexable
iv. Looks like tree rings under a microscope because of the way the osteoblast cells
secrete the matrix
b. Osteoblasts line up around a blood vessel
i. They secrete their product, form a layer of bone leaving the cell inside a hole
(lacuna)
ii. Tiny canals connect one lacuna to the next layer (lacuna)
c. Function – support, protection, stores calcium and other minerals.
i. Blood cells made inside the bone.
4. Tissue with a liquid matrix
a. Hematopoietic stem cells
i. Matrix (liquid) – plasma
ii. Blood cells suspended in the plasma
iii. No nucleus (red blood cells)
iv. WBCells – have nucleus
v. Small specs seen (platelets)
vi. Cardiovascular system
b. Functions – transportation of gasses, nutrients, wastes and other substances.
i. Cells made in another connective tissue
ii. Matrix not secreted by cells
iii. Moving matrix
Muscle Tissue
a. Characteristic – very cellular, very vascular
b. Function – movement , heat, support, protection
c. Classification: striations / non striations voluntary / involuntary
1. Skeletal muscle – striated, voluntary muscle
a. Long cylindrical cells
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b. Multi nucleated, obvious striations
c. Location : attached to bones combines with connective tissue and nervous tissue
d. Function: move or stabilize, heat production, protects internal organs, guard entrances
and exits of body.
2. Cardiac Muscle – striated, involuntary
a. Characteristics: cells are much smaller than skeletal muscles, cells tend to branch,
unicucleated, on a good slide you can see junctions (dark lines) called intercalated discs.
b. Some desimosomes and gap junctions (channel proteins)
c. Location: heart
d. Function: circulate blood and maintain blood pressure
3. Smooth Muscle – non-striated, involuntary muscle
a. Characteristic: cells are spindle shaped
b. Unicellular, big ovals
c. Location: anywhere you have a tube there is a smooth muscle – blood vessels,
respiratory, digestive, etc.
d. Function: move “it” through tube or control diameter of tube
e. Smooth muscle can be confused with dense regular connective tissue but connective
tissue collagen is wavy, smooth muscle is NOT WAVY
f. In dense regular, fiberblasts are flat, nucleus in smooth muscle is bigger and rounder.
Nervous Tissue -
1. Location: Brain, Spinal Cord, Nerves
2. Main Cell and Supporting cells
a. Neuron – cell body has nucleus, organelles. SOMA – name for cell body
b. Cell has extentions (2 types)
i. Dendrites – short extentions, one or many. Dendrites Deliver information.
ii. Axon – long extension, one per neuron. Axon take info Away.
3. Supporting Cells – group of 5 (to be discussed later)
a. All called Neuroglia
b. Function is to support neuron.
Membranes – combo of connective tissue and epitheal tissue
Four types. Mucus, Serous, Cutaneous, and Synovial
1. Mucus – lining cavities open to outside
a. Epithealium is usually stratified squamous or simple columnar
b. Loose connective tissue is areolar
c. In mucus membrane, Loose tissue is called Lamina Propria
2. Serous – simple squamous on top of loose connective tissue (areolar mainly)
a. Pleura, pericardium, peritoneum.
3. Cutaneous – skin
a. Stratified squamous on top of dense irregular
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b. Property of dense irregular is to stretch in different directions.
4. Synovial Membrane – epithealium on top of loose connective
a. Lines synovial joints (joints that have cavities (knee, elbow, hip)
b. Friction reduce synovial fluid
i. Very slippery
Integument System
1. Introduction: Largest organ system by weight
a. Includes skin, hair, nails, some glands and smooth muscles
b. General function: protection from foreign particles and chemicals, keep H2O in body,
temp control 2 ways sweat (vaso-dialate and vaso-constrict.)
c. Vitamin D production
d. Detection of Stimuli
e. Excretion – get rid of salts, water, organic waste
f. Blood reservoir – 5% of total blood volume.
2. Hypodermis: areolar loose connective tissue. 2/28/08
3. Epidermis – not vascular – stratified squamous on basement membrane
a. Cells of epidermis:
i. Keratinocytes
1. Produce keratin- fibrous protein that helps give skin its protective
properties – makes skin impenetrable to H2O
ii. Melanocytes – synthesize pigment (melanin – brownish, black pigment)
1. Gives color to skin and hair
2. Darker color = greater production of melanin
3. ¾ Keratinocytes = ¼ melanocytes
b. Stratum Basale (deepest layer)
i. Wavy baseline border (one cell layer thick)
ii. Melanocytes located here, sending pigment to layer of cells (exocytosis)
iii. Making layer above this
c. Stratum Spinosum
i. Several layers of cells
ii. Maybe a few mitotic
iii. Gearing up to make protein
1. Pre-kertin
d. Stratum granulosum – no more cell division at this point
i. Cells are alive on the basal side, dead on the apical surface.
ii. 3-5 cell layers thick
iii. Cells start to flatten
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iv. Granules – keratohyaline =>keratin + Lamellar bodies – Lamellar bodies filled
with lipid, as they die they eject lipids.
v. Organelles start deteriorating.
e. Stratum Lucidum
i. All the cells are dead
ii. Only a layer or two thick
iii. No longer see granules
1. Granules turned into the fibrous protein (keratin) and taken over the
cell (protein mold of the cell)
f. Stratum Corneium – thickest layer
i. All cells are dead
ii. Cell junctions: Desomones
iii. De-squamation (top layers flaking off)
iv. Lipids coat cells to keep them from drying out.
Thick Skin – has all five layers and a very thick strato-cornium (hands, palms, soles of
feet)
Thin Skin – no strato lucidum and all layers are thinner. (rest of the body)
Think skin is more flexible. **Hair only grows on thin skin
Callus – areas of increased friction, you will have thicker stratum corneum
SKIN COLOR
Melanocyte – makes pigment from yellow-red to brown-black.
Melanin migrates to the apical portion of the cell.
Albinism – genetic lack of pigment (have melanocytes but not the genetic information
for pigment production
Cyanosis – bluish grey tinge in skin of people not getting enough oxygen
Jaundice – yellow coloration of skin and whites of eyes due to bile pigment called
bilirubin
Carotenes – coloration from carrots
4. Dermis – two layers: Dense irregular tissue
a. Papillary Dermis – blood vessels that supply the epidermis.
i. Superficial receptors (light touch)
ii. In thick skin the dermal ridges push up on the dermal papilla – creates
fingerprints.
b. Reticular Dermis (majority) Stretch marks are tears in the dermis, wrinkles are folded collagen fibers
i. Deeply – blends into the hypodermis
ii. Dense irregular tissue
1. Collagen and elastic fibers in all directions
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iii. Lines of cleavage: in some areas the fibers (collagen) go more in one direction
then the other.
iv. Flexure lines – dermis kind of slides around. Dermis is better anchored in joint
side so it has to bend (fold at joints)
5. HypoDermis: areolar tissue – loose connective tissue and adipose tissue.
a. Attaches the skin to the underlying tissue
b. Fat storage tissue
c. Sub-cutaneous area – very vascular
6. Accessory structures
a. Hair structure
i. Shaft – above the epidermis
ii. Rood – everything below the epidermis
iii. Hair bulb – deepest end
iv. 3 layers of hair
1. Cuticle – outermost layer
a. 1 – 2 layers of overlapping cells (like roof shingles)
b. Hard keratin in them
2. Cortex – majority of hair – hard keratin
3. Core – Medula - soft kertin
v. Hair colored by same mechanism as skin
vi. Folicle: tunnel that hair grows in
1. Invagination of epidermis into the dermis around the follicle
Types of Hair: Terminal Hair – normal, thicker hair
Vellus hair – fine hair everywhere else.
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Glands in the Skin
1. Sebaceous Gland – Exocrine gland (Holocrine)
a. Secretes sebum into the hair follicle
b. Lubricates hair
c. Hair wicks sebum to skin surface
d. Has some antibacterial function
2. Sweat Glands – Exocrine gland
a. Mericrine sweat gland: Found everywhere (99% of sweat glands)
i. Secretes to surface through pores
ii. Functions:
1. Temperature control
2. H2O waste control
3. Antibacterial function
b. Apocrine sweat gland:
i. In hypodermis
ii. Sends product to hair follicle
iii. Only found in axillary and genital region
iv. Secretion has fat and carbs
v. Function: scent
3. Ceruminous glands – exocrine, found in dermis
a. Produces cerumin, a brown, tannish wax
b. In ear, used to trap foreign things
4. Mammary Glands : Apocrine exocrine gland
a. Secrete onto epidermis
Smooth muscle in dermis layer:
Connects the bottom 3rd of the hair follicle to the papillary layer of Dermis
Pulls the bottom of follicle, causes the hair to stand up straight.
Triggered by fear and cold
Vestigial function (no longer useful to us)
NAILS:
Nail body visible attached portion of the nail
Nail Bed underlying structure
Nail root Part of the nail imbedded under the skin
Eponychium cuticle – portion of stratus corneum on
the proximal nail body
Hypochium portion of stratus corneum under the
free edge
Lunula white half-moon at the proximal nail
body
Nail is made in the stratum basale invaginated into the dermis.
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Skin Cancer:
1. Basal Cell Carcinoma
a. Most common form of skin cancer (30% of white people will get it.)
b. Stratum basale cells invade Dermis/hypodermsi
c. Slow growing
d. Cured by surgical excision (99%)
2. Squamous Cell Carcinoma
a. Stratum spinosum
b. Grows rapidly and metastasizes if not removed
c. Involves head, ears, lower lip, hands
3. Melanoma – cancer of melanocytes
a. Most dangerous
b. Highly metastic and resistant to chemotherapy
c. 5% of skin cancers
Skeletal system – bones + cartilage + tendons (muscle to bone) + ligaments (bone to bone)
Functions:
1. Support – rigid support
2. Protection – shield organs
3. Movement – joints
4. Storage – calcium, phosphoras
5. Blood cell production
A) Tendons and cartilage
a. Hyaline cartilage most associated with bone cartilage
i. Grows appositionally (from inside to out by laying down layers)
ii. Injury repairs by interstitial growth (
b. Perichondrium – 2 layer membrane that surrounds cartilage
i. Outer layer is dense irregular connective tissue
ii. Inner layer – a row of chondroblasts
B) Classification of bones
a. Bone shapes
i. Long bones – longer than they are wide
ii. Short bones – about as tall as they are wide (wrists and ankles)
iii. Flat bones – no cavity inside (skull, sternum, ribs)
iv. Irregular bones (vertibra, some facial bones, ethmoid)
v. Sesamoid bones – bone that grows within a tendon (patella-kneecaps)
1. Acts as a fulcrum and gives more mechanical strength.
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C) Bone terminology
a. Epiphysis – ends of long bones
b. Diaphysis – long portion of long bones
i. In an adult there is a line between the epiphysis and the diaphysis called the
epiphyseal line. In immature bone it will be a line of hyaline cartilage called the
epiphyseal plate (growth plate.
c. Medullary cavity – hollow cavity in diaphysis (bone marrow area)
i. Bone marrow types
1. Red marrow – bone marrow that is actively producing blood cells
2. Yellow marrow – bone marrow that has stopped producing blood cells
and is now used for fat storage.
3. In adults, red marrow is only found in the proximal epiphysis of long
bones and in the marrow of the axial skeleton.
4. In children, all marrow is red marrow.
d. Outer layer of bones has 2 layers (periosteum)
i. Outer layer is dense irregular connective tissue
ii. Inner layer is a layer of osteoblasts (same as cartilage but with different cells)
iii. Periosteum connected to bone by fibers
1. Sharpey’s fibers – collagen fibers of the bone matrix that become part
of the outer layer of the periosteum making the connection of the layer
so strong it can take part of the bone with it when forcefully pulled off.
e. Endosteum – inner lining of bone, looks like the second layer of outer layer but has both
osteoblasts (actively making bone), and osteoclasts (actively breaking down bone).
i. The outside layer of the edosteum (toward center of bone) is covered with
articular cartilage (hyaline).
f. Calcium phosphate – major inorganic component of bone (glue).
g. Compact bone
i. Systems – functional units of compact bone = osteons
1. Contain a number of concentric rings
2. Osteon has a hollow center (central canal) that contains the blood
vessels. (Haversian canal)
3. Between the lacuna where the osteoblasts are, there are tiny tunnels
called canaliulis that allow nutrients and waste to difuse to and from the
cell.
4. Individual layers within an osteon are called concentric lamellae.
ii. Volkmann’s canals are canals perpendicular to central canals that bring in blood
vessels.
iii. Circumferential lamellae – concentric layers of bone around the outer area of
the bone.
1. Fed by arteries in or near the periostomine
iv. Interstitial lamellae – small bits of compact bone between the osteons
1. Fed by vessels in Volkmann’s canals.
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h. Spongy bone
i. Trabeculae – functional unit of spongy bone
1. Inside the struts of trabecula are lacuna in bone
2. Blood supply comes from Volkmann’s canals
a. Trabeculae built around these blood vessels
b. No osteons
ii. Most spongy bone in epiphysis (ends) of long bone
1. Some inside irregular bones
iii. Tiny bits of spongy bone line the inside of the medullary cavity (diaphysis or long
area of long bones)
D) Bone development or growth a. Develops through a process of ossification (turning other tissue into bone)
i. Intramembranous ossification
1. Model – Dense irregular connective tissue
2. Bones – Skull bones and clavicals
3. Proceeds from the inside out
4. Growth process
a. Blood vessels grow into the Dens. Irreg. Conn. Tissue model
i. They bring the osteoblasts with them
b. Osteoblasts begin turning the model into bone from the inside
out
c. Creates spungy bone out to the edges of the model
d. At the edge, the osteoblasts line up: makes a periosteum
i. A row of osteoblasts on the layer of dense irregular
connective tissue.
e. The periosteum on the outer edge of the spungy bone directs
the production of compact bone.
5. Ossifies dense irregular connective tissue (skull bones and clavicals)
ii. Endochondral ossification
1. Model – hyaline cartilage – has a perichondrium around it
(chondroblasts and dense irregular connective tissue)
2. Bones – all the rest
3. Proceeds from the outside out
4. Growth process
a. Chemical message sent to cartilage model that tells the
chondroblasts to die.
i. About 90% will die (all in the perichondrium)
b. Blood vessels grow into the perichondrium and osteoblasts
replace the dead chondroblasts and thereby turning it into a
periosteium.
i. Begins to produce dense bone
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c. Matrix inside the hyaline cartilage begins to break down
allowing blood vessels to invade and grow into the center of the
cartilage model. Then the remaining matrix in the center begins
ossifying (spongy bone)
d. As the spongy bone center is formed, osteoclasts go in and
begin to breakdown the bone to hollow out the center of the
bone which becomes the medullary area.
e. There are several ossification points. The diaphysis is primary
and the two epiphysis are secondary.
f. The epiphysis is created the same way as the diaphysis except
there are no osteoclasts; spongy bone is solid throughout.
g. The 10% of chondroblasts that did not die become the cartilage
layer between the diaphysis and the epiphysis. This is the
ephyseal plate (growth plate).
Bone Growth 1. Bones that have ossified intramemberously grow appositionally (adding layers to
outside).
i. The process of ossification proceeds toward the fontanels.
2. Bones that ossify endochondrally grow both appositionally and endochondrally.
i. Bones get thicker by growing appositionally
ii. Bones get longer by growing endochondrally
1. Epiphyseal plate growth – as the cartilage grows, the layer behind
ossifies.
Bone Remodeling 1. Goes on all the time (all bone in the body is replaced every 7 years)
2. Remodeling is the process of changing the thickness or shape of the bone.
a. Response to
i. Growth
ii. Stress
iii. Calcium needs
iv. Fracture
b. Growth – as the bone grows, the hollowing out of medullary cavity is
remodeling of that bone.
c. Stress – (gravitational stress)
i. Use it or lose it – if we don’t have the weight bearing on our bones, they
will stop growing.
ii. Decreased stress:
1. Osteopenia (thinning)
2. Osteoporosis
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iii. Increased stress
1. Bone growth at stress points.
2. The angle of the trabeculae (spongy bone) run in the line of
stress to optimize strength.
d. Calcium reservoir
i. Through hormonal messages we can take calcium from blood and
deposit it to bone OR if the blood is low on calcium, then hormonal
messages will take calcium from the bone.
ii. Carried out by osteoblasts and osteoclasts.
e. Fracture – most common bone pathology
i. Heals well due to vascularity (6-8 weeks for an uncomplicated fracture
ii. Upon a fracture bleeding occurs creating a fracture hematoma
iii. Initially the model for ossification is the fracture hematoma
iv. Re-growth of blood vessels occurs.
v. Brings fibroblasts and chondroblasts into the area
vi. Forms fibrocartilage (fibrocartilaginous callus formation)
vii. Osteoblasts ossify fibrocartilage (bony callus)
viii. Bone re-modeling occurs but bone is never exactly the same
ix. Healed bone is stronger because of the fibrous nature of fibrocartilage
vs hyaline cartilage.
Vertebral Column
Cervical 7
Thoracic 12
Lumbar 5
Sacrum 1 (5 fused)
Coccyx 1 (4 fused)
Spin Curvature
At Birth – Primary Curve
Holding head up – secondary curve
Standing produces a 2nd secondary curbe (lumbar)
Function: Help to align the central body over a point axis
Act with the discs to absorb shock.
Curvatures in the lateral plane – no curves in normal spine.
Any curves laterally are called scoliotic cuves.
Curves laterally in the thoracic area compressing the space inside the thoracic
cavity. (Developmental Problem)
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1. InterVertebral Disks
1. Anulus Vibrosis – fibro cartilage.
i. Made in layers around the nucleus
1. The bundles of collagen fibers are interwoven together.
2. As you put more pressure on the disk, the fibers get tighter around the
gell.
2. Nucleus pulposus – thick jell
3. The jell can bulge or herniated through the disk. Mostly happens L4-L5 and L5-S1 Also
C5—C6.
2. Skull Bones
1. Function: Protect the brain and guard the entrances to the digestive and respiratory
systems
2. 22 Bones
i. 8 form the cranium
1. Occipital, Parietal(2), Frontal, Temporal(2), Sphenoid, Ethmoid
ii. 14 associated with the face
1. Maxillary (2), Palatine bones(2), Nasal (2), Vomer, Inferior Nasal
conchae (2), Zygomatic(2), Lacrimal(2), Mandible
iii. 7 additional bones associated with the skull
1. Hyoid, Auditory ossicles(7)
3. 4 Major Sinuses: Frontal, Sphenoid, Ethmoid, Maxilla
i. Function: lighten the various skull bones and provide extensive area of mucus
emithelium.
4. Sutures: Lambdoidal, Sagittal, Squamosal, Coronal
5. The Orbit is composed of 7 bones: Frontal, Zygomatic, Maxilla, Palatine, Sphenoid,
Ethmoid, Lacrimal
Joints
Joints are classified in 2 ways, by Structure and Function
Structural classification parameters:
1. What tissue type is holding the joint together
2. Does it have a joint space (space within the joint bounded by a fibrous border)
Functional classification has only one parameter: How much movement is in the joint?
1. Snyarthrosis – no movement
2. Amphiarthrosis – little movement
3. Diarthrosis – freely movable (most of our joints)
Structure Classified Joints:
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Fibrous Joints – three types
1. Sutures : held together by dense fibrous connective tissue
a. No joint space – ex. Between skull bones
b. Functional category – synarthosis
2. Syndesmosis: bones held together by a ligament
a. There is a greater distance between the bones then in sutures
b. No joint space
c. Example: radio-ulnar or distal tibio-fibular ligamants
d. Functional cagegory – Amphiarthosis
3. Gomphosis
a. Pegs sitting in sockets – teeth
b. Bones held together by a ligament ( periodontal ligament)
c. No joint space
d. Teeth in maxilla and mandible
e. Function category – synarthosis
Cartilaginous Joints – Two types
1. Synchondrosis
a. Bones held together by hyaline cartilage
b. No joint space
c. Example – costo-sternal joints and epiphyseal plates
d. Functional category – amphiathrosis
2. Symphysis
a. Held together by fibrocartilage reinforced with ligaments
b. No joint space
c. Example – pubic synthesis and disks between vertebral bodies.
d. Functional category – amphiarthosis
Synovial Joints ( six types ) 1. All held together by a joint capsule reinforced by ligaments
a. 2 part joint capsule
i. Outer fibrous portion which is continuous with the periosteum
ii. Inner synovial membrane which produces synovial fluid
b. All bones in this category have articular (hyline) cartilage on their ends
c. All have joint space filled with synovial fluid
d. Synovial fluid is secreted by the synovial membrane and has the consistency
of molasses and is high in hyaluronic acid
e. If functions to lubricate the joint, absorb shock, and provide nutrients to the
articular cartilage.
f. There are Bursae associated with these joints. A bursa is a fluid filled pocket
created by synovial membranes in or near a joint.
g. Their function is to reduce friction between tendons or ligaments or bones
and the surrounding tissue.
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h. Continuations of these bursae surrounding tendons is called a tendon
sheath. – this insures smooth motion of tendons.
2. Functional category – Diarthosis – all are freely movable
a. Some are more movable then others.
b. If the joint only moves in one plane it is monoaxial
c. If the joint moves in 2 planes it is biaxial
d. If the joint moves in all three planes it is triaxial or multiaxial
e. Six types
Joint Description Example movement
Gliding Flat surfaces gliding across each other Manubrioclavicular joint. Biaxial
Hinge Gate and post Elbow and Knee Monoaxial
Pivot Bony process that rotates within a bony ring C1 on C2 Monoaxial
Ellipsoidal Modified ball and socket. Instead of
spherical heads they are ellipses
Atlas-occipital joint Biaxial
Saddle Like a rider over a saddle Carpo-metacarpo Biaxial
Ball and Socket Spherical head in a concave cup Hip and Shoulder Multiaxial
Type of motions possible at joints:
1. Flexion – Movement in the Anterior – Posterior plane the decreases the angle
2. Extension – Movement in the Anterior – Posterior plane that increases the angle
3. Abduction – Movement Away from the longitudinal axis (midline) of the body
4. Adduction – Movement toward the longitudinal axis of the body
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5. Rotation – spinning about a fixed point
Special movements
6. Lateral Flexion – side bending of the vertebral column at the cervical or lumbar regions.
7. Inversion – twisting motion of the foot which turns the sole medially
8. Eversion – twisting motion of the foot which turns the sole laterally
9. Dorsiflexion – motion at the foot which elevates the toes and sole
10. Plantarflextion – motion at the food with elevates the heel
11. Opposition – motion of the thumb touching the other digit
12. Reposition – motion of the thumb away from the other digit
13. Protraction – Movement of the mandible anterior
14. Retraction – Movement of the mandible posterior
15. Elivation – Movement of the jaw or scapulae in the superior direction
16. Depresion – movement of the jaw or scapulae in the inferior direction
17. Supination – movement of the palm to face anterior when in the anatomical position
18. Pronation – movement of the palm to face posterior when in the anatomical position
19. Circumduction – A combination of movement including flexion, extension, abduction, adduction
and rotation, usually at shoulder and theoretically possible at the hip.
Ribs Ribcage: Form a fused cage the will not bend laterally but will flex anterior and posterior to a
degree.
1. First 7 pairs of ribs articulate directly with the sternum through their own costal
cartilage. These are called Verterosternal Ribs.
2. Pairs 8,9, 10 use common cartilage to attach with the 7th ribs costal cartilage. These
are called Vertebrochondral Ribs
3. Pairs 11 and 12 float and are called Vertebral Ribs
4. Posteriorly, al l ribs articulate with the thoracic Vertebrae.
End of Section 2 for lecture test.
SECTION 3
Membrane Potential Electrons stored on the (-) side of a batter and will flow toward the (+) side.
The negative and positive side of a battery is separated, this is called a Charge Separation.
The difference between the positive side and the negative side is the Potential.
A cell is similar to a battery, the inside of the cell is one side and the outside of the cell is the
other side. The cell wall is the charge separation.
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Inside the cell there are many proteins that carry a negative charge.
The Ion with the largest concentration inside the cell is Potassium (K+)
The Ion with the largest concentration outside the cell is Sodium (Na+)
The charge inside the cell is more negative then the charge outside the cell,
This charge difference is the cell’s RESTING MEMBRANE POTENTIAL and is -70mv.
Potassium inside the cell wants to move outside the cell by diffusion and some does leak out.
Sodium outside the cell wants to move inside the cell by diffusion and some does leak out.
There are transport proteins which are ATP dependant (active transport), and pump Sodium out
and Potassium into the cell. These counter-transport membrane proteins are called the
sodium/potassium pump. This counter transport moves 3 Sodium ions out at the same time as moving
2 Potassium ions in (3 Na / 2 K). This pump maintains the resting membrane potential at -70mv.
A cell that is at rest is defined as a cell which is not being stimulated and has a potential of -70mv
DEPOLARIZING: CAUSING THE CHARGE (RESTING POTENTIAL OF -70MV) TO BECOME MORE POSITIVE (MOVE TOWARD 0 VOLTS)
REPOLARIZING: CAUSING THE CELL TO GO FROM A MORE POSITIVE STATE BACK TOWARD THE RESTING MEMBRANE POTENTIAL (-70MV)
HYPERPOLARIZING : DOING SOMETHING THAT MAKES THE CHARGE MORE NEGATIVE THAN THE RESTING POTENTIAL VOLTAGE.
Some cells use the resting membrane potential to do something. These “electrically excitable” cells are
muscle cells and neurons (nerve cells).
Stimulation can be Mechanical, Chemical, and Electrical
When you stimulate an electrically excitable cell, the MEMBRANE will respond by temporarily changing
its permeability to ions.
1. The size of the stimulus (weak or strong) will determine which ions and how much the
permeability will change
2. Weak stimuli will give rise to local potentials also called Graded Potentials
1. Event is short in duration
2. Confined only to the part of the cell membrane that is stimulated
3. At THAT point the cell membrane will become more permeable to Sodium (Na+) and
sodium will enter the cell at a higher rate then at rest. As the cell becomes more
positively charged from the Sodium ions it begins to Depolarize.
4. If it is weak stimuli, then it will cause depolarization no further than 56mv.
5. When the cell is done responding to the stimulus (the area that was more permeable
to Na+) goes back to its original permeability and the sodium/potassium pump pumps
out the excess Na+ and the cell is returned to its resting potential of 70mv.
3. Strong Stimuli give rise to Action Potentials
1. These events are long in duration
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2. They effect the entire membrane of the cell and may spread to the next cell.
3. Radiating out from the point of stimulus, the membrane will become more permeable
to Na+ and then more permeable to K+
4. The strong stimulus, by definition, is one that can depolarize a cell to -55mv. This
number is called the THRESHOLD and is a magic millivoltage at which action potential
begins.
i. The cell will depolarize to +30mv, then repolarize to -70mv, then hyperpolarize
to -90mv. That whole thing is the ACTION POTENTIAL.
ii. When the cell is done responding to the stimulus at -90mv, the
sodium/potassium pump will bring the membrane potential back to -70mv
5. The threshold is the point where electrically triggered protein gates open.
i. At -55mv the majority of the Sodium channels open allowing Sodium to come
rushing in.
ii. At +30mv the Sodium channels close and the Potassium channels open allowing
potassium to rush out of the cell which plunges the voltage down to -90mv.
iii. At -90mv the potassium channels close and the sodium/potassium pump brings
the cell back to the resting potential (-70mv)
6. Refractory period
i. Absolute refractory period: When the membrane is generating an action
potential and it is within the periods of depolarization and/or repolarizaiton.
1. You cannot cause a second action potential during this time
ii. Relative Refractory Period: If the membrane is in the hyper polarization phase of
the action potential, you can restimulate if the stimulus is STRONGER than the
original stimulus.
4. Weak stimulus cannot cause rise to action potential, but if you give a cell multiple weak stimulus
very close together before the cell can completely recover from the first stimuli and by this
adding stimulus the voltage rises to 55mv it will trigger a strong stimulus and therefore action
potential.
1. This effect of weak stimulus is where the term Graded Potential comes in.
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Muscle
Functions
1. Generates Heat
2. Protection
1. Movement
2. Guards entrances and exits
3. Helps maintain posture
4. Guards body organs not
protected by bone
Fascia: fibrous connective tissue that
wraps around outside of muscle and
separates muscles from each other.
Epimysium: outer covering of muscle
itself that holds a bunch of fascicles
Fascicle: consists of an outer wrapping
called perimysium which holds the
muscle cells inside.
Sarcolemma: muscle cell membrane
(muscle cell is a multi nuclei cell), also
Myofibril: Long cylindrical fiber consisting of 2 kinds of proteins, ACTIN and MYOSIN
o Myosin: thick filament
o Actin: Thin filament
o The bands visible on a muscle cell are related to way Actin and Myosin are organized
Sarcoplasmic reticulum is the endoplasmic reticulum of the muscle tissue.
Sarcomere: functional unit of muscle contraction:
A discrete unit of a myfibril
Funs from Z-line to Z-line
1. Dark band contains both Actin and
myosin and is called the A-band
2. A band runs from the beginning of
the myosin filament to the end of
the myosin filament
3. Where there is only myosin is called
the H band
4. M-Line is the center of the H-zone, a protein staple that holds down the myosin
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Actin Filament: Thin filament, G-Actin molecule Has a special site called an active site Tropomyosicn: thin twisted rope line filament that covers the active sites on the G-Actin F-Actin: two strings of G-Actin together.
Troponin – Three glovular molecules: One has an affinity of G-Actin, One has an affinity for tropomyacin and one has an affinity for calcium.
Myosin Fiament: Thick Filament
Holds an ATP
Head has an affinity for the
active sites on G-Actin
Sliding filament theory: Actin is pulled by and over the myosin filaments
1. Cross Bridge attachment: when the
myosin head attaches to the Actin
2. The myosin head pivots and moves
the Actin
3. To disconnect the head, there must
be an ATP that attaches to the
myosin head
4. The ATP is broken down and the
energy is ready
5. Will go to the next Actin
6. At full contraction there is no H
zone
i. Z lines are close together
ii. I band is smaller
7. Terminal system: ATP dependant
pumps store calcium
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8. Shortens until actin overlaps in H-Zone, It cannot get any shorter than the length of the myosin (A-
Band)
9. To relax, calcium is pumped back into the terminal systerna
Rigor Mortis: Stiffing of individual muscles
Begins 3-4 hours after death
Peaks at about 12 hours
Begins to dissipate after 48-60 hours
Mechanism
1. Death
2. No further ATP production
3. Calcium leaks out of the terminal systerna
4. Muscle contraction occurs
5. No ATP present to allow myosin heads to release
6. Eventually the structure breaks down and the muscle relaxes
Sequence Excitation Contraction (how the whole thing is triggered from the nervous system)
Axon (nerve) is attached to muscle cell.
Action potential carried onto the muscle cell.
Synapse – transfer of an action potential from one cell to the next by chemical means.
Neurotransmitter – Chemical substance that can cause an action potential on a cell membrane
Made by the axon. Accetocoline released by presynapsis and binds to post. Action potential
spreads.
Electrical event:
Action potential brought inside the muscle cell by the T-tubule
As the action potential goes past the terminal systerna, they release their calcium
Calcium is spread around.
MOTOR UNIT: axon & all the muscle cells that it attaches too.
The number of motor units activated determines the amount of force.
Individual muscles in ONE motor unit are spread out in the muscle
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The individual muscle rule: All or None: each motor unit is either fully contracted or not
contracted at all.
The smallest muscle uses 4 motor units and the larger muscles use as many as 100.
Small motor units give more control (hands)
Everything up to the myosin head pivot is in the lag phase.
In whole muscle – tension (how much shortening you have in the whole muscle) is dependent on how
many motor units are contracting in that muscle.
Stimulus Motor Units Whole muscle
Sub Threshhold No contraction No tension
Threshold Max contraction Some tension
Sub Maximum Max contraction More tension
Maximum Max contraction Max tension
There are two ways to control the amount of muscle tension
1. Multiple motor unit summation
1. Larger and larger stimuli to contract more motor units
2. Progressively larger stimuli at same intervals
2. Multiple wave summation
1. Same size stimuli but given at a faster and faster frequency
Tetany: sustained maximum muscle contraction
-no relaxation
Incomplete tetany: a small amount of relaxation
Complete tetany: cannot sustain due to fatigue
Fatigue is unavailability of ATP
Ca pumped back into sarcoplasmic reticulum
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Origin- Attachment point that does not move when the muscle contracts
Belly – The middle of the muscle mass itself
Insertion – When the muscle contracts, the insertion moves toward the origin
Control of the amount of tension that a muscle transmits is governed in two ways:
1. Multiple motor unit stimulation
i. Bigger and bigger stimulus, using more and more motor units up to max when all
motor units are contracted.
2. Multiple wave stimulation
i. Same size stimuli at a greater and greater rate of stimuli.
Fatigue: inability to provide enough ATP for continued contraction
Incomplete tetani – some relaxation
Complete tetani – no relaxation
Treppe – a warmup phenomenon of muscle
Less contraction when muscle is “cold”
Terminal cisternae warm up to release full calcium and time for calcium to spread out in the
muscle.
Muscle tone: in all whole muscle some motor units are always turned on (keeps them “warm”)
When a nerve is severed – muscle loses tone
Decreased muscle tone can lead to atrophy which is a decrease is muscle cell size
In other words – muscle cells decrease in size with no use.
Hypertrophy – opposite of atrophy: muscles grow larger with use, the cells grow bigger due to
more myofibrals.
Iso = same
Isometric – no change in length – generating tension with no shortening of the muscle
-the muscle cannot overcome the load.
Isotonic – same force
Lifting – same tension with muscle shortening because it overcame the load.
Most muscle actions involve both isotonic and isometric contractions.
** When you have actin and myosin in an ideal relationship, your muscle is at its strongest point. There
is a length – tension relationship. When the muscle is in mid-length, the muscle is at its strongest.
Energetics
ATP is Broken down to ADP and the energy is stored as Creatin Phosphate which is more stable.
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In aerobic activity (peak activity), Creatin phosphate is broken town to convert ADP to ATP which uses
the stored ATP.
Slow twitch vs Fast Twitch muscles
Slow twitch fibers contract more slowly but they are more aerobic so they can maintain their
contraction longer.
Fast twitch fibers contract faster but are more anaerobic and therefore they can’t sustain their
contraction of any length of time.
Most muscle cells are a little of both.
Conditioning:
Strengthening muscles become more effective users of oxygen.
Conditioning can actually teach fast twitch muscles to become a little more aerobic
When seen, slow twitch muscles ten to more redder while fast twitch muscles tend to be white.
This is due to myoglobin [slow twitch] helping store oxygen in the muscle
-Cardiac vs smooth vs skeletal (see book)
Nervous System:
Function: maintain homeostasis
Monitoring internal and external sensory input
Central nervous system – brain and spinal cord & nuclei
Peripheral nervous system – cranial nerves and spinal nerves
o Sensory [afferent] arriving information
o Motor [efferent] exiting information to muscles and glands
Motor information
Skeletal muscles, Cardiac Muscles, Smooth Muscles, Glands
o Somatic (controlled consciously) – skeletal muscles
o Autonomic (automatic control) – cardiac, smooth, glands
Neurons
These cells are similar to normal cells but cannot divide because they have NO CENTRIOLES
o Neucleous = group of cell bodies in the central nervous system
o Ganglia = group of cell bodies in the peripheral nervous system
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Dendrites: direct information toward cell body (also
called a Soma)
Branches of the dendrite are the dendritic spine
Axon is the nerve fibers and the attachment point to the
nerve cell is called the Axon Hillock.
The axon terminals or synaptic bulbs are also called the
terminal boutons (those pesky French)
1) An axon can conduct an action potential to a dendtrite of
another neuron
2) An axon can conduct directly with the cell body of
another neuron
3) An axon can synapse with the axon of another neuron.
Neuron Functional Classification
1) Many Dendrites : One Axon
a. Main neuron of the CNS
b. Uses as a muscle neuron
c. Interneurons (between nerves in the CNS)
d. Has myelin sheaths
2) Bipolar neuron – special sensory
a. No myelin sheath
b. One dendrite, one axon
3) Unipolar neuron
a. Dendrite becomes the axon
b. Sensory neuron (general – heat, cold, touch)
c. Have myelin sheaths.
Helper Cells
Neuroglia (Also called glial cells) – support cells
1) Astrocyte – only found in CNS
a. Star shaped
b. Processes connected to blood vessels and axons
c. Functions
i. Structure holds up and holds together the axons and blood vessels
ii. Completely covers the blood vessels and therefore creates the blood brain
barrier
2) Ependymal cells- only found in CNS
a. Line the cavities of the brain
b. Functions
i. Make cerebral spinal fluid
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ii. Circulate cerebral spinal fluid using cilia
3) Microglia
a. Phagocytes of the Central Nervous system
b. These are a modified type of White Blood cells called macrophage
4) Oligodendricytes – only in Central nervous system
a. Cellular extensions, only wrap around axons (the sheaths)
b. Make myelin sheaths in the CNS
5) Schwann Cells – peripheral nervous system
a. Wrap around the axons, form the myelin sheath in the PNS
b. Entire cell is wrapped around the axon
c. Each can only wrap around one axon.
Axon Sheaths
1) Both Oligodendricytes and Schwann cells make myelin
2) Myelinated axons look white
3) On myelinated axon, the axon is resting in the Schwann cell like in a pillow, but it is not “jelly
rolled” and they look grey.
Myelin functions
1) Protects and insulates axons from other axons
2) Greatly increase the speed (150 times over non myelinated axons)
Neurotransmitter
Released by presynaptic terminal
Acetylcholine sterace (enzyme) – breaks down acetylcholine
Floats around in extracellular fluid
Acetycholine – [exititory post synaptic potential] -When neurotransmitter is exititory
Opposite effect would be Inhibitory post synaptic potential
A mixture of neurotransmitters and inhibitory types – higher concentration rules.
Neuromodulator: [not a neurotransmitter]
Substance that influences the sensitivity of neurons to neurotransmitters
Influence speed
Secreated by axons on axons
Pre Synaptic Facilitation – between axons, speeds up action potential
Pre Synaptic Inhabition – slowing down action potential
Central Nervous System
Brain
Spinal Cord
Neuclei
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1. Brain
a. Cerebrum (newer brain) –largest
i. 2 hemisphere (right and left)
ii. Lobes (names for bone it is under)
1. Frontal
2. Parietal
3. Temporal
4. Occipital
iii. Structure
1. Fold – gyrus
a. Pre-central gyrus – frontal side
b. Post central gyrus – parietal side
2. Groove – sulcus
a. Lateral sulcus – separates temporal from parietal, frontal
b. Central sulcus – connects longitudinal fissure to lateral sulcus
(divides frontal/parietal)
3. Fissure – very deep groove
iv. 3 basic regions 1. Cerebral cortex – outside (grey matter) 1/8 inch thick.
a. Conscious mind
b. Motor areas, sensory areas and association areas
c. Recognition and integration of all sensory input
d. Functional areas of the Cerebral cortex:
i. Prefrontal area
1. Most anterior, association area, motivation,
mood, emotional control, behavior, personality
ii. Premotor area
1. Located just anterior to precentral gyrus
2. Staging area for motor functions
3. Decides (plans) which muscles to contract, in
what order, how strong
4. Sends the plan to the primary motor cortex
iii. Primary Motor area
1. In precentral gyrus of frontal lobe
2. Controls voluntary movement especially fine
control
3. Functions are arranged topographically from
medial to lateral. (pyramidal system)
4. Distributed disproportionately because the face
and hands require finer movement
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5. Right primary controls right side and left
controls right.
iv. Primary sensory area
1. Conscious perception, identification of pain,
pressure, temperature and touch.
2. Afferent fibers carry this information from
sensory receptors in skin and proprioceptors.
3. Proprioceptors are special pressure receptors
that send information about the position of
body parts in space.
4. Located in the post central gyrus of the parietal
lobe. Just posterior to Central sulcus
v. Sensory association area
1. Located posterior to the post central gyrus
2. Integrates and analyses different sensory inputs
with past sensory experiences.
vi. Visual association area
1. Posterior to the sensory association cortex and
anterior to the primary visual cortex within the
occipital lobe.
2. Integrates and analyses the information coming
from the primary visual area.
3. Interprets based on past visual experiences.
vii. Primary visual area
1. Most posterior within the occipital lobe
2. Cerebral medulla – deeper (white matter)
a. Myolaned axon fibers-Allows efficient and rapid movement of
information
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b. Collections of cell bodies - Nuclei
c. Efferent fibers take info out to the motor units
d. Afferent fibers bring info in from sensors
e. Connects to other parts of the cerebral cortex and to other
parts of the CNS.
f. Three categories of tracs:
i. Association fibers: connect areas of cerebral cortex in
the same hemisphere
ii. Commissural fibers: connect the hemisphere to the
other
iii. Projection fibers : connect the cerebrum to other parts
of the brain and the spinal cord.
3. Grey nuclei – islands of gray matter deep inside the white matter area
v. White matter is myolated axon (information moves at high speed)
vi. Grey matter – unmyolated axon, cell body, dendrites
1. Integration center – (decisions are made)
2. Peripheral (outer part of brain)
b. Wernicke’s area – Speech Area
i. Usually in the left hemisphere (85-90%)
ii. Responsible for understanding and formulating speech
c. Broca’s area (motor speech), on the same side as wernicke’s area
i. Programs sequence of motor contractions to speak
ii. Plans for speech sent to primary motor area
iii. Fed by the middle meningeal artery (susceptive to stroke)
MEMORY 3 types
1) Sensory – very short memory, 1-2 seconds unless something stands out
2) Short term – a few seconds to a few minutes.
a. Limited by the amount of information
b. Lost with distraction
3) Long term memory
a. Important short term memory is stored
b. 2 types
i. Declarative – stores facts
ii. Procedural memory – development of skills (riding a bike)
Diencephalon area of the brain
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Thalamus, Epithalmus, Hypothalamus + midbrain and brainstem are the “Old Brain”
1) Thalamus – largest part
a. 2 egg shape structures
b. Intermediate mass – connects the two structures
c. Sensory information gets sent to the thalamus – The thalamus routes the action
potentials
d. Gives you a crude sense of what’s coming based on the amount and intensity of
data
2) Epithalamus – posterior to the thalamus
a. Has the pineal body which plays a role in puberty and is the #1 regulator of
sleep/wake cycle (melatonin)
3) Hypothalamus – underneath (inferior) to the Thalamus
a. MOST INFERIOR part of the diencephalon
b. Has groups of nuclei divided by function
c. Mammillary bodies – nuclei which are involved with olfaction and swallowing
d. Pituitary Gland (sits in the Sella Tercica)
i. #2 part of the sleep/wake cycle
ii. Infundibulum (bridge to pituitary gland)
iii. MASTER ENDOCRINE GLAND
iv. About 11 other functions
BRAIN STEM –
1> Midbrain – Smallest part of the brainstem
1. Corpora quadrigemini
i. 2 superior colliculus (nuclei) : Visual Reflexes
ii. 2 inferior colliculus: Auditory reflexes
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2. Cerebral peduncle – descending nerve tracs from cerebrum down to other parts of the
brain and spinal cord.
2> Pons – inferior to midbrain – part of transit system for ascending and descending tracs
1. Inside pons are nuclei that regulate respiration
2. 3rd sleep/wake center
3> Medulla Oblongada
1. Ascending and descending tracs.
2. Nuclei for involuntary movement
i. Breathing, heart, sneezing, blood vessel dilatation, swallowing, coughing,
vomiting
3. Information for sense and motor cross here
4. Cranial nerves leave here.
Coordinated Functions- many parts of the brain work together
1) Reticular Formation
a. Responsible for arousing and maintaining consciousness and the sleep/wake cycle
b. General anesthesia work through this part of the brain
c. No activity here and consciousness is turned off
2) Limbic System – Diencephalon and cerebrum
a. Emotion, mood, visceral responses to emotion (like puking), pain and pleasure centers
b. Strong tie to taste, smell, feremones
c. Lesions here can result in extreme appétite
d. Smell and food tied to emotions
3) Cerebral Nuclei – The breaks for muscle contraction
a. Basal Nuclei – group of functionally related nuclei located in the cerebrum and the
diencephalon
i. Plays a roll in starting, stopping and monitoring movement
ii. Inhibits unwanted movement
iii. Unnecessary movment called dyskineses
1. Tics, excessive eye blinking, head bobs
2. Choreas – brief purposeless movements of head and extremities
Cerebellum Posterior and inferior to the cerebral hemispheres
1) 2 hemespheres held together by vermis
2) Arranged similarly to cerebrum
3) Connected to brain by 3 big “cables”
a. Cerebellar peduncles – nerve tracs
b. Feeds into brainstem
c. Superior, middle and inferior pairs
4) Compare intended movements with the actual movements and makes corrections.
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a. Effected by alcohol
b. Problems here can create poor tone.
3rd Hour Exam ends here.
SPINAL CORD
Covered by Dura Matter, arachnoid matter and pia matter
From foraman magnum to L-2 (solid cord)
31 pairs of nerve fibers
2 enlargements at the Cervical and Lumbosacral
These provide extra wiring for upper and lower extremities
Conus medullaris – a tapering of spinal cord to a tip at L-2
A piece of fibrous connective tissue that connects the conus medullaris to the coccyx is
called the Filum Terminale
Cauda equine – the splay of nerves at the distal end of spinal cord (horses tail)
Anterior root or horn carries motor information
Posterior root or horn carries sensory information
Ganglion on posterior root has sell body of sensory nerves (Unipolar Neuron)
Meninges – 4 – 5 layers
Mexix – a single layer
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1. Dura Matter consists of 2 layers
a. Periosteal layer
b. Meningeal layer
2. Arachnoid matter
3. Pia Matter – directly attached to the brain
Subdural space has veins
Subarachnoid space has arteries
-There is cerebral spinal fluid
Ventricles – spaces in brain
1. Lateral Ventricles (left and right)
2. Third Ventricle – in diencephalon around the intermediate mass of
thalmus
3. Fourth Ventricle - connected to via cerebral aqueduct
Appendable cells : cells that line the ventricles and produce CSF
Choroid plexus : complexes of appendable cells and blood vessels
Lateral aperture in the 4th ventricle is an opening that allows CSF into the subarachnoid
space.
Arachnoid Villus: where the CSF goes into the subdural matter where it goes back into
the bloodstream
Functions of the CSF
Cushions
Helps feed the brain (contains glucose, the brain’s favorite food)
Peripheral Nervous System
Cranial nerves
Spinal Nerves
Axon- Schwans Cells (myelin Sheath, covered with Endoneurium)
Fasicle – bunches of nerves
Endoneurium – holds many fasicles
Ganglia
Cranial nerves – numbered anterior to posterior I. Olfactory nerve – (smell) olfactory trac, olfactory bulb – purely sensory
II. Optic Nerve – crosses at optic chasm – visual cortex – purely sensory
III. Occulamotor – motor to eye muscle (4 muscles) – purely muscular
IV. Trochlear – motor to eye muscle (1 muscle) – purely muscular
V. Trigeminal – Senses forehead, cheek, jaw, motor – mastication (chewing) – sense and
motor
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VI. Abducens – motor to eye muscle (1 muscle) purely motor
VII. Facial nerve – motor for facial expression, sensory for anterior 2/3 of tounge - motor
and sense
VIII. Vestibulochoclear – hearing and balance – purely sensory
IX. Glossopharyngeal – swallowing, throat (motor), Taste 1/3 posterior tongue, Sense to
throat (gag reflex) – motor and sensory
X. Vegas nerve – longest cranial nerve. Motor – throat, thoracic, abdominal organs.
Sensory – taste: posterior 1/3 + thoracic and abdominal organs – sensory and motor
XI. Accessory- Motor – trapezius and sternocleidomastoid – purely motor
XII. Hypoglossal – motor to tongue
Acronym for nerves:
On Old Olympus’s Towering Top A Fallen Viking Goes Valiantly Across Hills
Motor/Sensory Acronym
Sum Say Marry Money But My Brother Says Be Brave Marry Mary
Spinal Nerves
Each spinal nerve except C1 has a specific area of sensation.
Dermitone – area of sensation that can be traced back to a specific nerve.
Mixed nerve – carries both sensory and motor
1. Posterior: serves posterior motor and sensory
2. Anterior serves anterior motor and sensory
a. Brachial plexus (upper extremities)
i. Originates from spinal nerves C5-T1
ii. Braids together Five major nerves
1. Axillary nerve – deltoid
2. Radial nerve – triceps, wrist, finger
3. Musculocutaneous – brachialis, Biceps brachial
4. Ulnar nerve – wrist flexers, finger flex
5. Median nerve – wrist flexors, and muscles of palm and hand
b. Lumbosacral Plexus – L4 in common
i. Lumbar Ventral - spinal nerves L1-L4
ii. Sacral – Ventral rami of spinal nerves L4-S4
iii. Produce nerves for lower extremities
c. Femoral Nerve – motor to anterior thigh muscle
d. Sciatic nerve – Longest peripheral nerve
i. Posterior to thigh and splits into 2 nerves
1. Tibial nerve – muscles of posterior or thigh leg and foot
2. Common fibular – lateral and anterior muscles of the leg and foot
Reflexes Most basic function the nerve system can do
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Componants
1. Sensory receptor
2. An afferent (sensory) sensory
3. An integration area or association nerve (only contained in spinal column)
4. An efferent or motor neuron
5. An effecter organ (skeletal, smooth, cardiac muscle or gland)
Pain Withdrawl
a. Same side flextion
a. Remove a limb from painful stimuli
b. Flexure muscles
b. Same side inhibition to extension
a. IPSP (inhibitory pre-synaptic synapse potential)
c. Opposite side extension
Stretch reflex – stretch receptors.
Autonomic Nerves – involuntary motor, cardiac, smooth
2 motor neurons together from a ganglia
No upper motor neuron (all reflexive)
Four major differences between sympathetic and parasympathetic
1. Sympathetic chain ganglia – on both sides of spinal cord (close)
a. 1st Cell body lives in the lateral horn (T1-L2)
b. 2nd Cell body lives in sympathetic chain ganglia
c. THEREFORE Pre ganglia nerves are short, post ganglia nerves are long
2. Parasympathetic
a. 1st cell body located in either in brain stem nuclei or in sacrael portion of the
spinal cord and is MUCH LONGER than the post ganglionic neuron
b. For one stimulus you get less items responding
THEREFORE:
1. Sympathetic T-1 to T4
2. Sympathetic Preganglia SHORT, Postganglia LONG
3. Sympathetic One stimulus effects many organs due to ganglionic chain
4. Parasympathetic Brainstem or S2-S4
5. Parasympathetic Pre ganglionic neuron LONG, Postganglionic SHORT
6. Parasympathetic One stimulus effects one or two organs