Cells

I. Basic History_______ living thing, from the tiniest bacterium to the largest whale, are made of one or more cells!

Before the seventeenth century, no one knew that _______ existed.

Every

CELLS

I. Basic HistoryMost cells are too _______ to be seen with the _____________.

Not discovered until after the invention of the ____________ in the early 17th century.

smallunaided eye

microscope

II. Important ScientistsA Dutch drapery storeowner ________________________, became the _______ person to _________ and __________ MICROSCOPIC ORGANISMS and LIVING CELLS.

Anton von LeeuwenhoekFIRS

TOBSERVEDESCRI

BE

II. Important Scientists1665: the English scientist

_______________ used a microscope to examine a thin slice of ______ and described it as consisting of “a great many little boxes”. It was after his observation that Hooke called what he saw “_______”. They looked like “little boxes” and reminded him of the small rooms in which monks lived. So he called them “_______”.

Robert Hooke

cork

cells

cells

Illustration of Corkdrawn by Robert Hooke

II. Important Scientists1824: the French scientist

Henri Dutrochet, concluded that ______ and ________ tissue were always made up of cells.

1831: Robert Brown named the _________

plant

animal

nucleus

II. Important Scientists1838: German botanist

Matthias Schleiden concluded that all ________ are made of cells.

1839: German zoologist Theodor Schwann reported that _________ are also made of cells.

plants

animals

II. Important Scientists1845: Felix Dujardin studied

the living cell and noted it contained a material called _____________.

1855: German physician Rudolf Virchow induced that ALL cells come from _____________ cells.

protoplasm

preexisting

II. Important ScientistsThe COMBINED work of Schleiden,

Schwann, and Virchow makeup what is now known as the modern _____________.cell theory

III. The Cell Theory Consists of 3 Principles

1. All living things are ____________ of one or more _______.

2. _______ are the basic units of ___________ and __________ in an organism.

3. Cells come ______ from the _______________ of __________ cells.

composedcells

Cellsstructure function

ONLYreproduction

existing

IV. Two Types of Cells1. _______________ = cell that

contains a _________ and _______ ___________ ____________________

Ex: ________, fish, mammals, _________ and ________

EUKARYOTE nucleu

sother

plants insectshumans

membrane-bound organelles

IV. Two Types of Cells1. _______________ = cell that

_______ a _________ and _____ ___________________ __________.

Ex: _____________ organisms such as __________ and their relatives

PROKARYOTE nucleu

sother

lacks

unicellular

bacteria

membrane-bound organelles

V. Cell DiversityoNot all cells are _______.oCells within the same organism show enormous diversity in ____, ______, and ____________________.oYour body contains at least _____ different cell types!

alike

sizeshape

internal organization

200

VI. Cell Size:oA few types of cells are large enough to be seen by the _________ eye.o_______________ is the _________ cell in the body and can be seen without the aid of a microscope.

oMost cells are visible only with a ____________.

unaidedFemale

egglargest

microscope

VI. Cell Size:o________________________________:1. Cells are limited in size by the

_______ between their _____________________ and their ________.• As a cell’s size increases, its volume

increases much faster than its surface area.

• (see picture on the next slide!)

Most cells are small for 2 reasons RATIO

outer surface areavolum

e

VI. Cell Size:2. The cell’s nucleus (the brain) can

only control a certain amount of living, active cytoplasm.

VII. Cell Shape:o_________ of shapes

oThe _______ of the cell depends on the __________.

Variety

shape

function

VII. Cell Shape:o Ex: ____________ that

carry information from your toes to your brain are long and threadlike.

o Ex: ____________ are shaped like round discs that can squeeze through tiny blood vessels.

Nerve cells

Blood cells

VIII: Cellular Organizationo_______________________ are made up of many cells, each of which is specialized to perform a distinct function.o Digestion, movement, respiration,

filtering, etc.o__________________ DO NOT carry out ALL life functions, but rather depend on each other.

Multicellular organisms

Individual cells

VIII: Cellular Organizationo ________ = a group of cells

functioning together to perform an activity.o Ex: muscle and nerve tissueso Ex: Plant tissues = stem and root

o ________ = groups of two or more tissues that function together.o Stomach, leaf of a planto Cooperation among organs makes life

functions within an organism efficient.

Tissue

Organs

Summary Cells Tissues Organs

VIII: Cellular Organization

Microscope Basics

Always carry a microscope with one hand holding the arm and one had under the base.

What’s my Power?

multiply

powerocular

lenspower

objective

o To calculate the power of magnification, __________ the _______ of the _____________ by the _______ of the ____________.

Ocular lens (10X)Objectives

(4X, 10X, 40X)

O

O O

oLow PoweroOcular lens = 10XoObjective = 4X

oTOTAL magnification for LOW power = _________

What’s my Power?

40X

oMedium PoweroOcular lens = 10XoObjective = 10X

oTOTAL magnification for MEDIUM power = _________

What’s my Power?

100X

oHigh PoweroOcular lens = 10XoObjective = 40X

oTOTAL magnification for HIGH power = _________

What’s my Power?

400X

oWe can see better details with ________ powers of magnification, but we can’t see as much of the image.

Comparing Powers of Magnification:

HIGHER

Which of these images would be viewed at a ______________ of magnification?

higher power

Microscope Pictures

Compound Light Microscopeso You will be using a compound light

microscope in several labs.o These microscopes have a

maximum magnification of 400Xo So you __________ see most of the

organelles like ribosomes, Golgi bodies, lysosomes, etc.

o More powerful microscopes are needed (2000X plus)

CANNOT

Common Problem . . . AIR BUBBLESAIR BUBBLES

AIR BUBBLES

Stained Onion Cellso Can you identify the cell walls?o Can you identify any other

organelles?

Stained Cheek Cells

Elodea – Typical Plant Cells as seen with the light microscope

Animal Cell

Nucleus

Rough ER

Golgi Body

Mitochondria

Chloroplasts

Ribosome

Cytoskeleton

How to Make a Wet-Mount Slide1. Get a clean slide and cover slip from your teacher.2. Place ONE drop of water/iodine in the middle of the slide. Don’t use too much or the water will run off the edge and make a mess!3. Place the edge of the cover slip on one side of the water/iodine drop.4. Slowly lower the cover slip on top of the drop.

5. Place the slide on the stage and view it first with the LOW power objective. Once you see the image, you can rotate the nosepiece to view the slide with the different objectives.

Let’s give it a try . . .1. Turn on the microscope and then rotate the

nosepiece to click the LOW power objective into place.

2. Place a slide on the stage and secure it using the stage clips. Use the coarse adjustment knob (large knob) to get the image into view and then use the fine adjustment knob (small knob) to make it clearer.

3. Once you have the image in view, rotate the nosepiece to view it under different powers. Draw what you see on a piece of paper.

BE CAREFUL WITH THE LARGEST OBJECTIVE! Sometimes there is not enough room

and you will not be able to use it!

Organelles of the Cell

NucleusAppearance: Large ovalLocation: variesFunction: control center for all cell functions

CytoplasmAppearance: clear fluidLocation: inside the cell membrane

Function: suspends organelles site of chemical reactions

NucleolusAppearance: Round structure inside the nucleus

Location: inside the nucleus

Function:Site of RNA synthesisProduces ribosomes

Plasma (Cell) MembraneAppearance: surrounds cellLocation:

Plant: in cell wallAnimal: outer layer

Semipermeable Composed of lipids & proteins

Function: controls materials in and out of the cell

Smooth Endoplasmic ReticulumAppearance: mesh of hollow sheets

Location: connected to the nucleus and plasma membrane

Function: Smooth: produces lipids

RibosomesAppearance: small, dense granules

Location: Free in the cytoplasm; attached to the rough ER

Function: Synthesize proteins

Golgi BodyAppearance: Flattened sacs

Location: Near the ERFunction: Temporary storage, packaging and secretion of proteins and fatsProduces lysosomes

MitochondriaAppearance: usually bean shaped with folded membranes (greater surface area – hence more energy)

Location: many mitochondria in a cellFunction: Powerhouse of the cell (energy production ATP)

VacuolesAppearance:

cavities filled with fluid Location:

Plant: usually 1 large water- filled vacuole (maintains structure)

Animal: many tiny vacuolesFunction: storage of water, starch fats,

etc.Two types:

Contractile vacuole: removes water and wastes

Food vacuole: breaks down food

Water Vacuole

LysosomesAppearance: egg shaped, membrane- bound structure

Location: ONLY found in animal cells

Function: Contain digestive enzymes that break down molecules aid in digestion of nutrients break down destructive cells (bacteria)

CytoskeletonAppearance:

network of thin, fibrous proteins (microtubules & microfilaments)

Location: entire cellFunction: acts as sort of a scaffold to

provide support for organelles helps maintain cell shape

MicrofilamentsAppearance:

long, threadlike proteinsLocation: a part of

cytoskeletonFunction: associated with

muscle contractions in large organismsassociated with cell movement

MicrotubulesAppearance:

thin, hollow cylinders of proteins

Location: a part of cytoskeleton

Function: provide shape and rigidity to the cellAssist organelles to move from

place to place within the cell

CiliaAppearance: thin hair-like projections

Location: formed from specialized microtubulesAttached to outside of cell

Function: aid in movement and locomotion (lungs and intestinal cells)

FlagellaAppearance: whip-like tails

Location: formed from specialized microtubulesAttached to outside of cell

Function: aid in movement and locomotion (sperm)

ChromatinAppearance: strings of “spaghetti”

Location: inside nucleusFunction: uncoiled DNA; involved in duplicating cells. Coils into chromosomes during cell division.

ChromosomesAppearance: coiled chromatinLocation: inside nucleusFunction: contains genetic information (DNA)

CentriolesAppearance: two small structuresLocation: found inside the centrosome (only in animal cells)

Function: moves chromosomes during cell division

Plastids (plants only)

Appearance: varies; have own DNA

Location: ONLY in plants

Function: based on type: Leucoplast (store starch), chromoplast (store pigments), chloroplast

Chloropast (plants only)

Appearance: small, circular, green (contains chlorophyll-green pigment)

Location: ONLY in plants

Function: site of photosynthesis

Cell Wall (plants only)

Appearance: made of cellulose; rigid, strong, stiff structure

Location: surrounds cell membrane (ONLY in plants)

Function: support and protectionAllows H2O, O2, CO2 to pass into and

out of cell

NOTE: All the ____________ work together!For example, after some proteins

are made by the ____________, the rough ER transports these proteins to the ___________________, then the Golgi makes vesicles that can fuse with the cell’s plasma membrane to release proteins to the _______________ outside the cell or used within the cell.

organelles

ribosomes

Golgi apparatus

environments

*ANIMAL CELL

Golgi body Smooth ER

Nucleolus

*Lysosome

Chromatin

Nucleus

*Vacuolemany small ones

Plasma Membrane

Rough ER

Microtubule

Mitochondria

*Centrioles

Ribosomes

Microfilaments

*PLANT CELL

*Plastid Microfilaments

Nucleolus

Plasma Membrane

Chromatin

Nucleus

*Cell WallRough ER*Chloroplast

Smooth ER

Golgi body

Mitochondria

*Water Vacuole

Ribosomes Microtubule

Plasma Membrane

I. Maintaining Balanceo_______________________________?oCells need to maintain a balance

by controlling material that move in and out of the cell _______________.

How do cells maintain balance

HOMEOSTASIS

I. Maintaining Balanceo_______ molecules like water, oxygen, and carbon dioxide can move in and out of the cell _______.

o_______ molecules like proteins and carbohydrates ________

o___________________

Small

freelyLarge canno

tEliminating wastes

I. Maintaining Balance

Structure of the Plasma (Cell) MembraneoAll cells are surrounded by a ____________________.

oFunctions like a GATE, controlling what _______ and _______ the cell.

oThe cell membrane is ________________ or selectively permeable.

plasma membrane

ENTERS

LEAVES

semipermeable

Structure of the Plasma (Cell) MembraneoA ____________________________ only allows certain molecules to pass through.

oSome substances easily cross the membrane, while others cannot cross at all.

semipermeable membrane

oMade of a thin layer of ________ and __________o Made mostly of

_______________ molecules (Phosphate + Lipid)

o Phospholipids are a kind of lipid that consists of 2 FATTY ACIDS (_______) and PHOSPHATE GROUP (_______)

Structure of the Plasma (Cell) Membrane

lipidsprotein

sphospholipid

tailsheads

oCell membranes consist of TWO phospholipid layers called a ________________


LIPID BILAYER

oWater molecules surround ______ sides of the cell membrane.oPolar __________________ sticking

TOWARD the water (____________)oNonpolar __________ point AWAY

from the water (______________)


both

phosphate heads hydrophil

iclipid tails hydrophob

ic

oThe cell membrane is constantly being _______ and ______________ in living cells.


formed

broken down

oMoving with and among the phospholipids are cholesterol, proteins, and carbohydrates.o _____________oNonpolar, found among the phospholipids to help prevent the fatty acid tails from __________ together.

oHelps with structure and homeostasis

III. Lipid Bilayer

Cholesterol

sticking

III. Lipid Bilayer

o__________:o Found on the surface of the plasma

membrane = __________ signals to the inside of cell.

o Embedded in the plasma membrane = structure and support of cells shape, and _______ large substances in and out of the cell.

III. Lipid BilayerProtein

transmit

move

III. Lipid Bilayer

o_______________:o Attached to proteins, helps cells

identify _____________________o Ex: help disease fighting cells

recognize and attack a potentially harmful cell

III. Lipid BilayerCarbohydrates

chemical signals

Cellular Transport

oAll particles move and have _______ energy (energy of motion)

oMovement is ________ and usually in a ________________o Cells are mostly made of water and there

is a constant flow of ions and particles.

Cellular Transport

kinetic rando

mwater solution

1. ___________________ = movement of molecules across the membrane by using the molecules _________ energy. The cell exerts ___ energy!

2. __________________ = transport of materials against the concentration gradient and requires _________________.

IV. 2 Types of Cellular Transport

Passive transport

kineticNOActive

transport

cellular energy

o3 types of passive transport:1. ___________ = the net movement of

___________ from an area of __________ concentration of particles to an area of _________ concentration of particles

V. Passive Transport

Diffusionparticles

HIGHER

LOWER

oMolecules move __________ until they are _________ distributed.

oDiffusion continues until the concentration of substances is uniform throughout.

Diffusion . . .randomlyequally

o_____________________ = continual movement but no overall change in concentration.o Movement of materials

into and out of the cell at equal rates maintains its dynamic equilibrium with its environment.

Diffusion . . .Dynamic equilibrium

BALANCE

oDiffusion depends on the ________________________o __________________________ is the

difference between the concentration of a particular molecule in one area and the concentration in an adjacent area.

o Ex. Gas exchange in the lungs (oxygen from air to blood and carbon dioxide from blood to air)

Diffusion . . .

Concentration gradientConcentration gradient

2. _______________________ = type of passive transport that increases the rate of diffusion with the use of __________________

oEx: Facilitated diffusion of glucose

V. Passive TransportFacilitated diffusion

carrier proteins

Facilitated Diffusion . . .

3. _________ = the diffusion of _______ molecules from an area of HIGH water concentration to an area of LOW water concentration

V. Passive TransportOsmosiswater

oOccurs in response to the concentration of solutes dissolved in water!o _________ are dissolved substances in

a solutionoCytoplasm is mostly _______ containing

many dissolved _________.

V. Passive Transport: Osmosis

Solutes

watersolut

es

oBecause ___ TWO molecules can occupy the same space at the same time, the MORE solutes there are in a certain volume of water, the FEWER water molecules there can be in the same volume.

V. Passive Transport: Osmosisno

oPlant and animal cells behave differently because plant cells have a large water ________ and a __________


vacuole

cell wall

o Ex. Osmosis occurring in a slug (animal) cell


H2ONaCl

H2ONaCl

- water leaves the cell- cells shrivel, slug dies

A. ___________________ = a solution in which the concentration of dissolved substances (solutes) is the _______ as the concentration of solutes inside the cell.

o Osmosis ___________ occur since a concentration gradient is not established!

V. Passive Transport: OsmosisIsotonic solution

SAME

DOES NOT

o __________ - becomes ________ (limp)o plant wilts because

no net tendency for water to enter

What happens to cells when placed in an isotonic solution?

Plant cell flacci

d

o _____________ - normal

What happens to cells when placed in an isotonic solution?

Animal cell

B. _____________________ = a solution in which the concentration of solute is _________ than the concentration of solutes inside the cell.

V. Passive Transport: OsmosisHypotonic solution

LOWER

o _____________ - water will move through plasma membrane into the cell. This causes the cell to swell and internal pressure increase.o Cell _______ (bursts)

What happens to cells when placed in an hypotonic solution?

Animal cell

lyses

Drinking too much water

o __________ - normalo The vacuole & cytoplasm

increase in volumeo The cell membrane

is pushed harder against the cell wall causing it to stretch a little

o The plant tissue becomes stiffer (turgid)

What happens to cells when placed in an hypotonic solution?

Plant cell

Why they spray fruit in the grocery store.

B. _____________________ = a solution in which the concentration of dissolved substances is _________ than the concentration inside the cell.

V. Passive Transport: OsmosisHypertonic solution

HIGHER

o _____________ - will _________ because of decreased turgor pressure

What happens to cells when placed in an hypertonic solution?

Animal cellshrivel

Drinking salt water on a deserted island

o __________ - will lose water from __________ and a decrease in turgor pressure will occur; so it is _______________


Plant cell vacuole

plasmolyzed

Plants die when salt is spread on icy roads.

o _________________ = internal pressure of a cell due to water held there by osmotic pressure

o ______________ = the loss of turgor pressure causing the plasma membrane to pull away from the cell wall

o causes the plant to wilt


Turgor Pressure

Plasmolysis

Summary of Cell Behavior in Different Environments:

oMovement of molecules from an area of ______ to an area of _______ concentration (opposite of passive transport)

oREQUIRES _________________!oMoves large, complex molecules such as proteins across the cell membrane

VI. Active Transport

LOWHIG

Hcellular energy

o Large molecules, food, or fluid droplets are packaged in membrane-bound sacs called __________.

VI. Active Transport

vesicles

1. _____________ = process by which a cell surrounds and takes in material from its environment.

• Used by amoeba to feed and white blood cells to kill bacteria.

2 Types of Active Transport:Endocytosis

EndocytosisOutside of Cell

2. _____________ = expels materials out of the cell reverse of endocytosis

o Used to remove ____________________ _______________

o Proteins made by ribosomes in a cell are packaged into transport vesicles by the Golgi Apparatus

o Transport vesicles fuse with the cell membrane and then the proteins are secreted out of the cell (ex. Insulin)

2 Types of Active Transport:Exocytosis

wastes, mucus & cell

products

ExocytosisOutside of Cell

Cells

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