Anatomy & Physiology of Cells Chapters 3 & 4 Anatomy & Physiology

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Anatomy & Physiology of CellsChapters 3 & 4

Anatomy & Physiology

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Basic Cell Info

•Cell Theory - the cell is the fundamental organizational unit of lifeSchleidon & Schwann – first to suggest that all living things are

composed of cells

•Human body – _____ _____________ cells

•Cell diameter range: 7.5 micrometers (RBC) – 150 micrometers (ovum)

•Composite cell – generalized cell illustration we study that exhibits most important characteristics of many different dinstinctive cell types; no such cell exists in the body

•3 Main Cell Structures: • ___________ _____________• __________________ (with organelles)• _____________

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Nuclear pore

ChromatinCytoplasm

Plasma membrane

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Cell StructuresCell Structures

Plasma membranePlasma membrane Outer boundary of cellOuter boundary of cell Made of ___________, ____________, and other Made of ___________, ____________, and other

moleculesmolecules ____________ ______________model ____________ ______________model

molecules slowly float around the membranemolecules slowly float around the membrane molecules bound tightly to form continuous sheetmolecules bound tightly to form continuous sheet molecules bound loosely to slip past one anothermolecules bound loosely to slip past one another

Chemical attractions / forces hold membrane Chemical attractions / forces hold membrane togethertogether

Phospholipid ___________Phospholipid ___________ hydrophilic heads - polarhydrophilic heads - polar hydrophobic tails - nonpolarhydrophobic tails - nonpolar

Without _____________________ (steroid lipid), Without _____________________ (steroid lipid), membranes would break easilymembranes would break easily

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Plasma Membrane cont.Plasma Membrane cont. ____________________ permeable

__________-soluble molecules pass through easily __________-soluble molecules can not pass through

without help Membrane proteins:

how the cell controls movement of molecules “gates” that open and close to allow things into and out of

the cell Carbohydrates attached – glycoproteins

______________________ markers allow to distinguish between normal and abnormal cells

attack bacteria, cancer, blood transfusions _____________ attached – catalyze cellular reactions Other proteins attached – form connections between cells Receptors – react to hormones, etc. to trigger metabolic

changes; __________________ transduction

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Peripheral protein

HydrophobicPhospholipidtail

HydrophilicPhospholipidhead

Integral protein

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NucleusNucleus One of largest cell structures Occupies ______________portion of cell Shape and number in a cell vary (most common is one spherical

nucleus) Nuclear membrane - double membrane with pores

contains _____________________ pores called nuclear pore complex (NPCs) selectively permit molecules to enter or leave nucleus extensions of the ________________

Contains genetic material forms _______ chromosomes in _____________ cells Remains as ________________ in ______-dividing cells

Dictates structure and function of the cell Contains ________________

nonmembranous contains RNA synthesizes ribosomal RNA (rRNA) to combine with proteins to

make ribosomes cells that make more protein have bigger nucleolus

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CytoplasmCytoplasm Gel-like substance that makes up inside of cell Contains various organelles suspended in ___________________

(intracellular fluid) _______________ organelles - specialized sacs or canals made of cell

membrane Endoplasmic reticulum Golgi apparatus Lysosomes Peroxisomes Mitochondria Nucleus

____________________organelles - not made of a membrane; made of microscopic filaments Ribosomes Cytoskeleton

Fibers – microfilaments; intermediate filaments Centrosome Cell extensions – microvilli, cilia, flagella

Nucleolus

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OrganellesOrganellesEndoplasmic ReticulumEndoplasmic Reticulum

Flat, curving sacs in parallel rows

Two types ____________ ER

Contains ribosomes Extends from ___________ Protein synthesis and

intracellular transportation proteins move through

canals to the golgi ______________ ER

Synthesizes lipids and carbohydrates steroid hormones,

glycoproteins, membrane lipids

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Steps to processing and packaging1.ER delivers protein via vesicles2.Enters first cisternae3.Chemical modifications4.Sent to next cisternae via vesicle5.Further modification6.Repeated until last cisternae7.Packaged in secretory vesicle8.Migrates to cell surface9.Combines with membrane10.Secretes contents

Organelles cont.Organelles cont.Golgi ApparatusGolgi Apparatus

Membranous ________________ (sacs) stacked near nucleus Processes and packages molecules for export from

cell

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Organelles cont.Organelles cont.Lysosomes & PeroxisomesLysosomes & Peroxisomes

Lysosomes Membraneous sac Vesicles that pinched off from Golgi Size and shape change depending on activity Contains enzymes that if bust can kill the cell Destroys __________________ “digestive bags” , “cellular trashcan”

Peroxisomes membraneous sac Smaller than lysosome Contains enzymes (peroxidase, catalase) _________________ harmful substances Seen in kidney and liver cells

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Organelles cont.Organelles cont.MitochondriaMitochondria

Membraneous _____________ membrane Form a sac within a sac _______________ – inner

membrane folds contain enzymes – make ATP

Membranes same structure as plasma membrane

“power house” Liver - +1000

mitochondria Sperm cell – 25

mitochondria Exercise – increases

number of mitochondria

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Organelles cont.Organelles cont.RibosomeRibosome

Every cells contains thousands rER and free in cytoplasm Nonmembranous Protein synthesis (cell’s “protein

factory”) Ribosomes on ________ – export and cell

membrane use ________ribosomes – make proteins for

domestic use make structural and functional

proteins (enzymes) Large and small _________________

each has RNA bonded to protein rRNA

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Cytoskeleton

1. Cell’s internal __________________ network2. Made of rigid, rodlike pieces (support and movement)3. Muscle-like groups of fibers4. Twisted protein molecules

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CytoskeletonCytoskeleton Cell FibersCell Fibers

MicrofilamentsMicrofilaments smallest fibers serve as “cellular muscles” muscle cells – proteins slide past each

other Intermediate filamentsIntermediate filaments

slightly thicker than microfilaments supporting framework ___________ everything in the cell dense arrangement in cells on outer skin

layer MicrotubulesMicrotubules

thickest cell fiber “_____________” of the cell

move things around in cell cause movement of entire cell movement of vesicles movement of chromosomes in

mitoses

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Cytoskeleton cont.Cytoskeleton cont. CentrosomeCentrosome

Non-membraneous Very _____________ site Near ___________ Coordinates building and breaking of

microtubules “______________ organizing center” (MOC) Important role in cell division Centrioles found here

form microtubular cell extensions (see next slide) form _______________ in cell division

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Cytoskeleton cont.Cytoskeleton cont. Cell extensionsCell extensions

MicrovilliMicrovilli found in areas where

_________________ is important increases surface area of cell allows faster rate of

absorption found in epithelial cells that line

intestines cover surface of cell contain ____________________ 100s/cell

CiliaCilia contain _________________ main purpose – _________________ cilia shorter and more numerous

than flagella line respiratory tract; cilia moves

mucus to be swallowed FlagellaFlagella

contain microtubules main purpose – movement Only present in _______ ______

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Cell to cell contactCell to cell contact Gap junctionsGap junctions

It directly connects the _________ of two cells, which allows various molecules to pass freely between cells.

______________proteins connect plasma membranes

DesmosomesDesmosomes ________________ filaments

connect plasma membranes

specialized for cell-to-cell adhesion

Ex. Skin cells

Tight junctionsTight junctions join together the

______________ of adjacent cells.

http://www.youtube.com/watch?v=3Xb0PFFGblI

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PASSIVE Cellular PASSIVE Cellular TransportTransport

with concentration gradient with concentration gradient Moves from areas of HIGH to low Moves from areas of HIGH to low

concentrationconcentration Simple diffusion – movement of particles

through bilayer from high to low concentration 3 main categories

Dialysis – diffusion of small solute particles through selectively permeable membrane

Osmosis – diffusion of water Facilitated diffusion – diffusion of particles

through membrane with help of carrier proteins

Diffusion http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_diffusion_works.html

1. molecules densely packed when enter water 2. molecules collide in high conc. 3. gradually move away from each other toward low conc. 5. eventually evenly distributed

1. semipermeable membrane2. left – unbalanced3. right - homeostasis

Dialysis

OsmosisOsmotic pressure / tonicity – water pressure that develops in the solution with the higher concentration of impermeable solute (low water concentration)

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.html

Osmosis cont.

HypotonHypotonicic

IsotonIsotonicic

HypertoHypertonicnic

PressurePressure LowLow SameSame HighHigh

Solute Solute concconc

LowLow SameSame HighHigh

Water Water concconc

HighHigh SameSame LowLow

Cell Cell changechange

SwellsSwells SameSame ShrinksShrinks

http://www.coolschool.ca/lor/BI12/unit4/U04L03/osmosis.swf

plasmolysis crenation

Facilitated Diffusion

1.Carrier mediated2.Attracts solute to binding site3.Carrier protein changes shape 4.Solute can move to other side of memb

http://www.coolschool.ca/lor/BI12/unit4/U04L03/facilitated%20transport.swfhttp://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_facilitated_diffusion_works.html

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ACTIVE Cellular ACTIVE Cellular TransportTransport

_____________ concentration gradient _____________ concentration gradient From __________ to HIGH concentrationFrom __________ to HIGH concentration Uses carrier protein & _______________Uses carrier protein & _______________ Two main categoriesTwo main categories

EndocytosisEndocytosis- - movement of particles into the cell via movement of particles into the cell via secretory vesicles fusing with plasma membranesecretory vesicles fusing with plasma membrane Phagocytosis Phagocytosis -- taking in of __________ particles by taking in of __________ particles by

vesicles fusing with plasma membrane vesicles fusing with plasma membrane ““cellular eating”cellular eating”

PinocytosisPinocytosis – taking in of _____________ particles – taking in of _____________ particles (fluid) by vesicles fusing with plasma membrane(fluid) by vesicles fusing with plasma membrane ““cellular drinkingcellular drinking

ExocytosisExocytosis – movement of particles out of the cell – movement of particles out of the cell via secretory vesicles fusing with plasma membranevia secretory vesicles fusing with plasma membrane

Active Transporthttp://www.coolschool.ca/lor/BI12/unit4/U04L03/active%20transport_jeffedit.swf

Carrier protein uses ENERGY to move solute AGAINST conc gradient

3 Na+/2K+

Endocytosis

http://www.youtube.com/watch?v=DuDmvlbpjHQ

NameName Type ofType ofTransportTransport

DirectionDirectionOfOf

MovementMovement

ConditionsConditions ExamplesExamples

Diffusion 

passive TowardsLowerconcentration

Concentration gradient

Water, gases (02and CO2), and steroid hormones.

FacilitatedDiffusion

passive TowardsLowerconcentration

Concentrationgradient, pluschannel or carrierproteins

Water, glucose, and amino acids.

Osmosis passive TowardsLowerconcentration

Concentrationgradient,Channel Proteinsoptional

Water 0nly.

ActiveTransport

active TowardsHigherconcentration

Carrierprotein andATP energy

Ions, sugars,and aminoacids.

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EnzymesEnzymes Functional ______________ Catalyst ____________ activation energy

to start chemical reaction Not changed in reaction or

used up Tertiary/quaternary proteins Cofactor – inorganic, non

protein Coenzyme – organic, non

protein Active site – part of enzyme

where binds to substrate Lock-and-key model

Enzyme FunctionEnzyme Function ________________Effect________________Effect

Allosteric effector molecule binds to allosteric site

Active site’s shape is changed Inhibition or Activation of

enzymes Factors that have allosteric

effect pH Temp Cofactors being added/removed

Proenzymes – inactive enzymes Kinases

synthesize enzymes Convert proenzyme to enzyme

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1. Catabolism a. net __________ of energyb. Breaks down large molecules into smaller onesc. ex. cellular respiration

2. Anabolism a. net ____________ of energyb. Build large molecules from smaller onesc. ex. synthesizing DNA

Cell Metabolism

Cellular Disease

1.Cystic fibrosis a. ____ pumps in membrane missingb. Secretions (sweat, mucus) saltyc. Thick mucus causes lung infectiond. Respiratory & digestive problems

2.Diabetes mellitus/type 2a. Adult onsetb. Non-insulin dependentc. Obesity onsetd. Reduces ___________ receptors in memb

3.Cancersa. Abnormalities in __________b. Cause tumorsc. Hyperplasia: increase in number of cells/proliferation of cells

4.Genetic Disordersa. Sickle-cell anemia: mutation in _____________________ protein