Biology Exam Review 2011

8/6/2019 Biology Exam Review 2011

http://slidepdf.com/reader/full/biology-exam-review-2011 1/18

Biology Exam Review 2011

Taxonomy: The practice of classifying organisms.Each kingdom is sub divided several times into progressively smaller groups; a taxon.

For ex; bobcatDomain ± largest taxon domain eukarya

kingdoms (6) animalia

phylum chordata class mammalia order carnivora

family felidaegenus lynx

species ± smallest taxon lynx rufus6 kingdoms:

bacteria, Achaea, Protista, Animalia, Fungi, Plantae

genotypic: similarities which are genetic in nature, ex; # of chromosomes.

Phenotypic system: classifying by physical characteristicscladistic system: use phylogenic similarities (evolutionary similarities) ex; evolved from dinos

Prokaryotic and Eukaryotic CellsProkaryotic: ³before´ ³nucleus´ (no membrane bound organelles) but have ribosome¶s. No

mitochondria or endoplasmic reticulumKingdoms: bacteria, Achaea

Age: 3.5 billion years agoDNA material: concentrated in an area called ³NUCLEOID´. Single loop of double stranded

DNA, some have PLASMIDS (genetic material)

size: size of mitochondria (1-10 um)

- multi cellular forms are very rarereproduction: cell division NOT by mitosis and meiosis, most commonly A sexual.

R espiration: many are aerobic (don¶t need oxygen)

Eukaryotic: ³True´ ³Nucleus´ (complex membrane bound organelles, los of diversity in cellstructure)Kingdoms: Animalia, Plantae, Protista, Fungi

Age: 1.5 billion years old (single celled original) , 700 million years ago multi cellular formedDNA material: In membrane bound nucleus, genome arranged in CHROMOSOMES

size: 100-1000 um

reproduction: cell division by mitosis and meiosis, sexual reproduction

respiration: most are aerobic ± require oxygen




Viruses: particulate that contains strands of DNA or RNA surrounded by a protective proteincoat and that act as mobile genes that parasitize cells.

- non living: lifeless outside living cell , chemical within a host cell they can replicate- no cellular structures, therefore not an organism

- can cause diseases

Structure: DNA or RNA + CAPSID (protein coat ± 95%)Shape of capsid:- polyhedral (polio)

-cyndrical (tobacco mosaic virus)

KINGDOMS

Kingdom Bacteria & Kingdom Achaea- both are prokaryotic cells

How are they classified?

1. Shape of an organism:- Cocci (singular-coccus)-spherical-Bacilli (singular-bacillus)-rod shaped

-Spirilla (singular-spirilla)2. GRAM STAIN (only bacteria)

positive: bacteria have thick protein layer on their cell wall; stain purple.negative: have thin protein layer on their cell wall; stain pink

Kingdom Plantae

Characteristics:-all are multi cellular

-eukaryotic-all obtain food by photosynthesis

- 3 main parts; stem (tissue that supports leaves, transports nutrients), leaves (carries nutrients),roots (reach for nutrients, water /anchor)

- all 3 are adapted to land, all need water energy and nutrients

Kingdom Fungi




- fungi are heterotrophs- feed by releasing digesting enzymes into their surroundings, then absorbing the digested

nutrients into their cells- majority of fungi are multi cellular

- bodies are made of HYPAHE (singular hypha)

Mushroom: hyphae packed tightly together, most of the organism is undergroundMycelium: loose branching network of hyphae (underground part)Septa: hyphae divided into cells by cross walls, porous, allowing cytoplasm to flow through the

hyphae from cell to cell.Hyphae: without septa appear to be large branching, multinucleate cells.

Zygospore (zygomycotes)

club fungi (basidiomycotes)sac fungi (ascoycotes)

imperfect fungi (deuteromycotes)

KINGDOM PR OTISTA 3 general types:

Protozoa: animal like protists, are heterotrophs that imjest or absorb their food. No cell wall.Vary in shape and size. Most can move.

For example: flagallates- live inside of termites to help them digest the wood they eatAlgae: plant like protists, autotrophs that carry out photosynthesis. Simple aquatic chlorophyll

containing organisms. Range in size. Algae have been on earth for more than 2 billion years.Algae classified into 6 phyla on the type of chloroplasts and pigments they contain.

Slime moulds and water moulds: difficult to classify, they produce spores(fungi), they glidefrom place to place and imjest food(protozoa). Cellulose cell walls(plants) 2 groups of slime

moulds (plasmodial and cellular) and 1 group of water moulds (oomycotes).

UNIT 3Gas exchange:- single celled aerobic organisms do not have a respiratory system

- organisms need moist environments

- oxygen is dissolved in the water around the cell, diffuses through the outer membrane of

each cell thereby becomes available for cellular respiration.- at the same time carbon dioxide diffuses out

External Respiration: exchange of O2 and CO2 between air and blood

Internal Respiration: exchange of O2 and CO2 between blood and the cells of surroundingtissue

Cellular Respiration: complex series of chemical reactions that take place mainly in

mitochondria of cell.Medulla Oblongata : area of the brain responsible for controlling some of the bodiesreflexes. When the amount of carbon dioxide in the blood increases the medulla send out

nerve impulses to initiate faster movement of the muscles of the rib cage. Also, nerve

impulses are sent to the muscles in the diaphragm making it move more rapidly.- Increse CO2 levels because your exhaling around 4% CO2, , therefore inhaling around 4%

more CO2




How to Inhale and Exhale?In humans there are 2 muscular structures that control air pressure:

- intercoastal muscles: ventral surface of rib cage

- Diaphragm- muscle layer that separates the thoracic cavity from the abdominal cavity

Inhalation: Intercoastal muscles contract, lifting the rib cage up and out. At the same time,the diaphragm contracts and pulls downward. As the lungs expand, air moves in.

Exhale: Intercoastal muscles relax, allowing the rib cage to return to its normal position.The diaphragm also moves upward, resuming its domed shape. As the lungs contract, air

moves out.

O2 diffuses into blood and CO2 diffuses into lungs

Tidal Volume : volume of air inhaled and exhaled in a normal breathing movement

Respiratory reserve volume : additional volume that can be taken in beyond regular tidalinhalation

expiratory reserve volume: addition volume that can be forced out of the lung

vital capacity: tidal vol + inspr. Res. Vol. + exp. Res. Vol

residual volume: amount of gas in lungs and passageways bloodstream to the lungs

Transport Vessels3 types in mammals;

1) Artery, arterioles (small artery) all carry blood away from heart,MOST carry oxygenated blood (except pulmonary artery carry deoxygenated blood)

3 different structural layers :

Outer ² covering of connective tissue with some elastic fibres (pg 290)

Middle-think, circular bands of elastic fibres and smooth muscle (can expand and snap

back, helps to continue pumping blood)

Inner- single cell thick, smooth epithetical cells, help reduce friction

2) Vein, venules (small veins) all carry blood towards heart, MOST carry deoxygenated

blood

(except pulmonary vein carries O2 blood)

contains 2 times as much as blood as arterial system

blood is travelling slow after reaching capillaries, veins cant contract therefore above theheart, gravity will pull blood back to heart, below heart, muscle contractions and one way

valves (prevent backflow) assist the blood in returning to the heart. (veins lack elasticity, still

has the 3 layers)

3) Capillaries: where exchange of gasses/nutrients occurs. (pg290)

small, wall is single and endothelial cell layer, diameter just large enough for a blood cell.

Capillary wall regulates movement of fluids and other materials into and out of blood

stream*** remember that in a closed circulatory system, blood is always contained in capillaries

and never flows out to bathe the bodies cells directly

(diagram) gasses, foods, wastes, hormories are exchanged across capillary wall between blood and interstitial fluid bathing each cell of body




Open Transport System: system where the blood does not always stay contained within blood vessels. (Grasshopper)

- Circulate slowly- cannot provide rapid delivery of materials around the body

Closed transport System: blood does not bathe cells directly, but is pumped within a

network of vessels.- Animals need faster blood flow to transport respiratory gasses

Double circulatory: blood is pumped through the heart twice during every complete cycle.- Humans

Single circulatory: blood travels through the heart only once during every complete cycleControl of Heartbeat

SINOATRIAL NOTE (S-A Node/ Pacemaker) ² generates electrical impulse that spreads

over 2 atria, causing them to contract = 70 times/min

ATRIOVENTRICULAR NODE (A-V NODE) ² located near atria, between 2 ventricles

also generates on electrical impulse causing contraction of both ventricles

Electrocardiodiagram (ECG) ² used to measure change in voltage produced by electricalsignals

ACETYLCHOLINE: sent out to e decrease rate of firing of SA node.³Fight or flight´: nervous system releases adrenaline, when in attack, defence or escape.

Adrenaline, increases heart rate, increases blood flow to muscles causing more O2 to themuscles.

Cardiac Output: amount of blood pumped by heart, total level of work of muscles2 factors affect C.O:

1) heart rate = beats/min2) stroke volume (SV): blood forced out of heart with heartbeat

C.O = SV x H.R ; volume/beatBlood: collection of cells that are specialized for specific functions

2 elements;1. Plasma- fluid portion (55%) ± water ,proteins, dissolved gasses

2. Formed portion ± cells

RBC - 44% blood volume- function: o2 transport

- mature R.B.C ± no nucleus, with lots of pigment of haemoglobinhaemoglobin: picks up O2 in areas of high O2 concentration, and releases O2 in areas of low

concentrationRbc transports in CO2 blood: 9% is carried in plasma, 45% combines with water

O2 : measured in terms of partial pressure (usually highest in lungs, and lower in body tissues)

- low partial pressure Hg releases O2 - high partial pressure binds O2

Acidity:

high acidity release O2Low acidity bind O2

White blood cells: (leucocytes)- take up 1% of blood

- colorless, no nuclei




2 TYPES:macrophages: eating cells, ³innate immune response¶, can pass through capillary walls to engulf

pathogens

Lymphocytes: non phagocytic, acquired immune response (enables body to recognize then fendoff pathogens) T cells: thymus gland, B cells: bone marrowAntibody: produced by body, able to recognize foreign antigens carried by invading pathogens.

- only BIND with one antigenPlatelets: NOT cells, component of formed portion of blood, no nucleus, break down quickly in

the bloodBlood Plasma: medium in which blood cells are suspended

- 92% water - 7% proteins

- .14% organic substances- .93% inorganic ions

Blood group Preoten marker, antigen Antibody in serum GenotypesA A Anti b IaIa or Ia i

B B Anti A IbIb or Ibi

O None Anti A , Anti B Ii

Ab A and B None Ia Ib

Digestive System:

Mouth: - equipped with teeth

- surface of tongue covered with papillae (house tastes buds)- uvula: soft palate prevents food from entering pharynx

-saliva: secreted by 3 pairs of salivary glands assist in chemical process of digestion. Moistens, lubricates food so it will pass to digestive system.

Esophogas - food passes into tube called esophagus

- lines with circular and longitudinal muscles along its length ; 24cm- muscles work together to push food along

- musin: lubricant is secreted by a number of small, tubular glands located in the back of thethroat

Stomach - muscular j shaped, sac like organ whose interior lining is packed with millions of gastric

glands.

- Glands: secrete gastric juice important in digestion3

rdlayer of muscle fibres: oblique layer

chime: physically broken up good mixed with gastric juices

pyloric sphincter: contracts and relaxes to control flow of food leaving stomach

Small Intestine - subdivided into 3 regions Duodenum: U shaped, shortest and widest of regions, lacks layer of oblique muscle.

- Pancreatic and bile ducts open into duodenum




- important site for further chemical breakdown of partially digested materials.- Permanent, circular fluids in nocuous membrane.

- Folds increase surface area of intestine.

V illi: serve to further increase absorptive surface of intestinal tract

Lacteal Vessel: carry larger fat particles that are absorbed from intestine.

Flow into vessels of lymphatic circulatory system Jejunum: contains more folds and intestinal glands- break down remaining proteins and carbohydrates so the end products can be absorbed

Ileum: 3m long, contain fewer and smaller villi. , function is to absorb nutrients, pushremaining undigested material in large intestine

The Large Intestine - caecum, colon, rectum, anal, canal

- 1.5 m long, it is much shorter than small intestine- diameter is greater

- caecum: blind end of large intestine- appendix: organ that plays no role in digestion but fights infection

undigested food colon water, minerals + bacteria = feces- passes into rectum and anal canal which is last 20 cm of intestine

anus: rings of circular muscle called anal sphincters.

Ph Levels: Regulation of Digestive Enzymes: Nerves and hormones (chemical regulator secreted in one partof body and transported by bloodstream to another part, causing a response)

- Gastrin: stimulates digestive glands to secrete musin, pepsin, HCI, lipases-Secretin: presence of chime in duodenum stimulates duodenum to secrete it into bloodstream,

arriving at pancreas, stimulates cells to release an alkaline fluid containing NA2CO2 and NaHCO2, which increases pH from 2 to 8. (If the pH did not increase, none of the enzymes of

the intestine would function due to a too acidic environment)

Enzymes:




Leaves :

- primary organs responsible for photosynthesis

- PHOTOSYNTHESIS : plants absorb carbon dioxide and give off oxygen

- both photosynthesis and respiration require leaf to exchange gasses with

environmentSTOMATA : small structures in cuticle that help gasses to pass in and out of leaf

STOMA: consists of a pore bordered by a pair of guard cells, these cells allow the

pore to be opened to permit exchange of gasses.

- surfaces of leaf cell are moist to permit gas exchange to occur by diffusion

across the membrane

- In photosynthesis, oxygen is released into intracellular air space and can be used

for respiration

- Carbon dioxide released by respiring leaf enters intracellular space and can be

taken up by photosynthesis

Stems:

- contains small pores

- Stomata where gasses can enter the leaf

LENTICELS: arrangements of cells that provide openings from the environment

into tissue of stem.

- oxygen diffuses through stomata or lenticels into intracellular air space of the

plant, from there can reach every cell in the stem.

- In the plant, oxygen dissolves in the water of the moist cell membrane and then

diffuses across membrane into the cell.

- Carbon dioxide diffuses across cell membrane into intracellular air space then out

through pores.




Transportation in the plants:

TRANSLOCATION: movement of materials from one part of the plant to another

XYLEM: formed when certain plant cells thicken, providing structural support to

the plant.

Transportation in Xylem:

- roots take in water through root hairs and epidermal cells by osmosis

- water flows through cell walls, into intracellular spaces within the root and enters

xylem

- water then transported in the xylem tissue up the tissue into the stem, water and

materials move by diffusion

- materials enters leaf, conducting vessels, branch into lots of veins.

- from end of each vein, water and minerals diffuse into cells of leaf.

- 99% of water that reaches leaf is lost through transpiration




Root Pressure:

- roots build up pressure that forces water upward. 2 reasons for this:

1. Cells actively pump water into xylem tissue

2. Cells transport ions and in turn create concentration gradient that causes water

to move into xylem by osmosis.Cohension Tension:

- mechanism may act to pull water up the plant from above

- each molecule of water vapour evaporates from a stomata on the surface of the

leaf into air, another molecule is behind it.

- 2nd molecule moves up to replace first

- water will move up the xylem even when there is no transpiration taking place

from the leaves.

Mineral Transport:

- minerals are transported within plants in the xylem tissue- water moves into the roots of the plant by osmosis

- movement of minerals against concentration gradient proves mechanism other

then diffusion is at work in transport minerals in plant roots

Phloem...?

Mass flow theory:

- 2 membranes that are permeable to water but not to sucrose are connected and

immersed in water to form a closed system.

VASCULAR SYSTEMS

human vascular systems: consists of tubes that transport water, dissolved foodand oxygen throughout bodies; pushed around a heart.

Plants: specialized tissue for transporting material from one location to another

within the plant.

- Tissue consists of internal system of tubes that transport water and food

through plant.

Vascular Bundles: (Xylem and Phloem)

- Transport material within plant

DICOT STEMS: bundles form a discontinuous ring of vascular bundles.

MONOCOT STEMS: vascular bundles are scattered throughout the stem of theplant in no discernible pattern.

Structure of Xylem:

ANGIOSPERM: long, mainly hollow tubes formed by non living cell walls of tracheids or

vessel elements.




Stem Types:

Stolons: (runners)

produce new plants where the nodes in the stem touch the ground (strawberries)

Rhizomes: underground, horizontal structures stems. (iris)

Tubers: Enlarged rhizome section (Potato)Corms: bulbous underground structures (Dormant in winter)

Development in the Meristem:

Meristem: small regions of unspecialized tissue that divide by mitosis. When a cell in the

meristem divides, one of the two resulting cells remains in the meristem, the other

becomes part of the human body.

2 main types of meristem tissue:

1. Apical Meristem: located in roots and shoot tips of plants

- division results in growth of roots, leaves and flowers.- in root, protected by root cap

- in stem, protected by terminal bud

2. Lateral meristem: results in growth of tissue beneath the bark of tree stems

Most woody plants have 2 kinds of lateral meristems:

a. VASCULAR CAMBIUM: produces xylem and phloem cells in the stems and roots

b. CORK CAMBIUM: produces a tough covering for the surface of stems and roots (bark)

Hormonal Control of Plant Growth:

1. Promoter Hormones: cause growth (auxins)

2. Inhibitor Hormones: block growth (Ethylene)

Plant Tropism:

Tropism: directions growth response to unequal stimulation from the external environment

3 major kinds that are effected by light, gravity and touch.

PHOTOT ROPISM: growth of plant affected by light. Most plants are POSITIVE

PHOTOT ROPIC ² grow towards the light , roots are NEGATIVE PHOTOT ROPIC

GRAVIT ROPISM: response to gravity. Roots = negative (grow downwards)shoots and stem = upwards

THIGMOT ROPISM: response to plants to touch, behaviour caused by specialized cells in

epidermis of the plant. (Ex. Vining plants)

nastic movement: caused by stimulus that is not directional




Pedigrees:Sex Linked Inheritance:

Some traits passed from one generation to the next depend on the sex of the parent carrying thetrait. Transmission of genes that are located on one of the sex chromosomes, X or Y is called sex

linked inheritance.

Only on the x chromosome x linked . Only on the y chromosome y linkedEx. Color blind man marries a heterozygous female, what is the possibility that the offspringmay be colorblind?

Let XH

represent the allele for normal . Let Xhrepresent color blindness.

Xh Y

XH Hh Hy

Xh h h hy

50% normal ,50% colorblind

Autosomal Inheritance

Diseases/Disorders that are transmitted on any chromosome except the sex chromosomes.Autosomal Recessive Inheritance

Need both alleles to have the disorder ; ex. Tay SachsMeiosis

Meiosis is a type of cell division, occurs only in reproductive organs in the sex cells (sperm +

egg). Each human gamete contains 23 chromosomes.22 AUTOSOMES (general characteristics)1 sex chromosome (determines sex)

- Begins with diploid number, ends with haploid number




he organelles in eukaryotic cells allow them to perform more complex functions thanprokaryotic cells, which don¶t have these little organs. If you don¶t know much aboutorganelles, don¶t worry ± you¶ll be learning more in an upcoming instruction.

Some of the organelles in eukaryotic cells are:

y The Nucleus ± the ³brain´ or control center of the cell. It contains DNA, whichmakes up genes. That DNA gets transcribed, or copied onto messenger RNA.That messenger carries a copy of the genes orders for certain protein production.These orders go to the protein factories.

y Ribosomes ± These are the protein factories. They follow instructions frommessenger RNA (remember that the messenger RNA got its orders from theDNA). The instructions tell the ribosomes to make specific proteins. Note, thisparticular organelle is found in prokaryotes too!

y Endoplasmic Reticulum (ER) ± structures that modify proteins produced in theribosomes. Not all of the proteins made by the ribosomes need changing, butthose that do get ³altered´ here.

y Golgi Apparatus ± This structure will make even more changes to the proteinsthat already got changed when they were in the E.R. Remember those proteinswere made in the ribosomes, changed once in the E.R. and will be changedagain in the Golgi Apparatus. The Golgi also acts as a post office by packagingand shipping proteins to other parts of the cell or out of the cell.

y Mitochondria ± structures which produce the cell¶s energy, a.k.a. powerhouses

of the cell.

y Chloroplasts ± structures which allow plants to trap sunlight and carry outphotosynthesis.

There are some important differences between prokaryotic and eukaryotic cells.

Size

Eukaryotic cells are, on average, ten times larger than prokaryotic cells.




Enzyme Place Whereenzymes acts

Substrate Products Origin of Enzymes

Salivaryamylase

Mouth Starch Maltose Salivary Glands

Pepsin (likeslow pH 2)

Stomach Protein Peptides Stomach glands(Pepsinogen +HCI pepsin)

Lapase (likes apH 8)

Small Intestine

pH 8

Fats Glycerol + Fattyacids

Stomach glands ± (BUT doesnot becomeactive until insmall intestine)

Pancreaticamylase

Small intestine Starch Maltose Pancreas

Pancreaticlipase

Small intestine Fat Glycerol + fattyacids

Pancreas

VariousEnzymes

Small intestine Proteins, RNA,DNA, sugars,etc.

Variousmonomers

Small intestine,glands,pancreas, etc.

Unit 5Scientists involved in evolution theories:

Natural Selection: Causes change in the allele frequencies of a population, which can lead toevolutionary change. For example: Ayana the tall.

Acquired Characteristics:Divergent Evolutions:

- pattern of evolution in which species that were once similar to an ancestral species diverge or become increasingly distinct.

Convergent Evolution:- pattern of evolution in which similar traits arise because different species have independently

adapted to similar environmental conditions.

Surace area: volume ± smaller the better

Biology Exam Review 2011

Documents

Transcript of Biology Exam Review 2011