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Anatomy & Physiology of Cells
Chapters 3 & 4
Anatomy & Physiology
1
Basic Cell Info
•Cell Theory - the cell is the fundamental organizational unit of life
Schleidon & 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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Cytoplasm
Chromatin
Nuclear pore
Plasma membrane
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Cell Structures

Plasma membrane
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Outer boundary of cell
Made of ___________, ____________, and other
molecules
____________ ______________model
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Chemical attractions / forces hold membrane together
Phospholipid ___________
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molecules slowly float around the membrane
molecules bound tightly to form continuous sheet
molecules bound loosely to slip past one another
hydrophilic heads - polar
hydrophobic tails - nonpolar
Without _____________________ (steroid lipid),
membranes would break easily
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Plasma Membrane cont.

____________________ permeable
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__________-soluble molecules pass through easily
__________-soluble molecules can not pass through without help
Membrane proteins:
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how the cell controls movement of molecules
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Carbohydrates attached – glycoproteins
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“gates” that open and close to allow things into and out of the cell
______________________ 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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Hydrophilic
Phospholipid
head
Integral protein
Hydrophobic
Phospholipid
tail
Peripheral protein
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Nucleus

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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 _____________________
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pores called nuclear pore complex (NPCs)
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selectively permit molecules to enter or leave nucleus
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extensions of the ________________
Contains genetic material
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forms _______ chromosomes in _____________ cells
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Remains as ________________ in ______-dividing cells
Dictates structure and function of the cell
Contains ________________
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nonmembranous

contains RNA
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synthesizes ribosomal RNA (rRNA) to combine with proteins to make
ribosomes
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cells that make more protein have bigger nucleolus
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Cytoplasm
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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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Organelles
Endoplasmic Reticulum
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Flat, curving sacs in parallel rows
Two types
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____________ ER
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Contains ribosomes
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Extends from ___________
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Protein synthesis and
intracellular transportation
 proteins move through
canals to the golgi
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______________ ER
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Synthesizes lipids and
carbohydrates
 steroid hormones,
glycoproteins, membrane
lipids
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Organelles cont.
Golgi Apparatus
Membranous
________________ (sacs) stacked near nucleus
Processes and packages molecules for export from cell
Steps to processing and packaging
1. ER delivers protein via vesicles
2. Enters first cisternae
3. Chemical modifications
4. Sent to next cisternae via
vesicle
5. Further modification
6. Repeated until last cisternae
7. Packaged in secretory vesicle
8. Migrates to cell surface
9. Combines with membrane
10. Secretes contents
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Organelles cont.
Lysosomes & Peroxisomes
Lysosomes
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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
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membraneous sac
Smaller than lysosome
Contains enzymes (peroxidase, catalase)
_________________ harmful substances
Seen in kidney and liver cells
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Organelles cont.
Mitochondria
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Membraneous
_____________ membrane
Form a sac within a sac
_______________ – inner
membrane folds
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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.
Ribosome
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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 _________________
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
each has RNA bonded to protein
rRNA
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Cytoskeleton
1.
2.
3.
4.
Cell’s internal __________________ network
Made of rigid, rodlike pieces (support and movement)
Muscle-like groups of fibers
Twisted protein molecules
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
Cytoskeleton
Cell Fibers
 Microfilaments
 smallest fibers
 serve as “cellular muscles”
 muscle cells – proteins slide past each
other
 Intermediate filaments
 slightly thicker than microfilaments
 supporting framework
 ___________ everything in the cell
 dense arrangement in cells on outer
skin layer
 Microtubules
 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.
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Centrosome
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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.
Cell extensions

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Microvilli
 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
Cilia
 contain _________________
 main purpose – _________________
 cilia shorter and more numerous than
flagella
 line respiratory tract; cilia moves mucus to
be swallowed
Flagella
 contain microtubules
 main purpose – movement
 Only present in _______ ______
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
Cell to cell contact
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Gap junctions
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It directly connects the _________
of two cells, which allows various
molecules to pass freely between
cells.
______________proteins connect
plasma membranes
Desmosomes
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________________ filaments
connect plasma membranes
specialized for cell-to-cell adhesion
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Ex. Skin cells
http://www.youtube.com/watch?v=3
Xb0PFFGblI
Tight junctions

join together the
______________ of adjacent
cells.
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PASSIVE Cellular Transport
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with concentration gradient
Moves from areas of HIGH to low concentration
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
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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 membrane
2. left – unbalanced
3. right - homeostasis
Dialysis
Osmosis
Osmotic 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.
http://www.coolschool.ca/lor/BI12/unit4/U04L03/osmosis.swf
Hypotonic
Isotonic
Hypertonic
Low
Same
High
Solute conc Low
Same
High
Water conc High
Same
Low
Cell change Swells
Same
Shrinks
Pressure
plasmolysis
crenation
Facilitated Diffusion
http://www.coolschool.ca/lor/BI12/unit4/U04L03/facilitated%20transport.swf
http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_facilitated_diffusion_works.html
1.
2.
3.
4.
Carrier mediated
Attracts solute to binding site
Carrier protein changes shape
Solute can move to other side of memb
ACTIVE Cellular Transport

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_____________ concentration gradient
From __________ to HIGH concentration
Uses carrier protein & _______________
Two main categories
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Endocytosis- movement of particles into the cell via
secretory vesicles fusing with plasma membrane
 Phagocytosis - taking in of __________ particles by
vesicles fusing with plasma membrane
 “cellular eating”
 Pinocytosis – taking in of _____________ particles
(fluid) by vesicles fusing with plasma membrane
 “cellular drinking

Exocytosis – movement of particles out of the cell via
secretory vesicles fusing with plasma membrane
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Active Transport
http://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
Name
Type of
Transport
Direction
Of
Movement
Conditions
Examples
Diffusion
passive
Towards
Lower
concentration
Concentration
gradient
Water, gases (02and
CO2), and steroid
hormones.
Facilitated
Diffusion
passive
Towards
Lower
concentration
Concentration
gradient, plus
channel or carrier
proteins
Water, glucose, and
amino acids.
Osmosis
passive
Towards
Lower
concentration
Concentration
gradient,
Channel Proteins
optional
Water 0nly.
Active
Transport
active
Towards
Higher
concentration
Carrier
protein and
ATP energy
Ions, sugars,
and amino
acids.
Enzymes
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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
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Enzyme Function
________________Effect
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Allosteric effector molecule binds to
allosteric site
Active site’s shape is changed
Inhibition or Activation of enzymes
Factors that have allosteric effect
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pH
Temp
Cofactors being added/removed
Proenzymes – inactive enzymes
Kinases

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synthesize enzymes
Convert proenzyme to enzyme
Cell Metabolism
1. Catabolism
a. net __________ of energy
b. Breaks down large molecules into smaller ones
c. ex. cellular respiration
2. Anabolism
a. net ____________ of energy
b. Build large molecules from smaller ones
c. ex. synthesizing DNA
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Cellular Disease
1.Cystic fibrosis
a. ____ pumps in membrane missing
b. Secretions (sweat, mucus) salty
c. Thick mucus causes lung infection
d. Respiratory & digestive problems
2.Diabetes mellitus/type 2
a. Adult onset
b. Non-insulin dependent
c. Obesity onset
d. Reduces ___________ receptors
in memb
3.Cancers
a. Abnormalities in __________
b. Cause tumors
c. Hyperplasia: increase in number of
cells/proliferation of cells
4.Genetic Disorders
a. Sickle-cell anemia: mutation in
_____________________ protein