Transcript Chapter 3 Cells

PowerPoint Lecture Outlines
to accompany
Hole’s Human
Anatomy and Physiology
Tenth Edition
Shier w Butler w Lewis
Chapter 3
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
3-1
A Composite Cell
• Is a hypothetical cell
• Cells are differentiated (suited for their particular
purpose)
•Examples
•Neurons
•Muscle cells
•Sperm
•Egg
3-3
Cells…..
• 3 Fundamental pieces needed in a cell
– Plasma membrane:
• phospholipid bilayer
• Proteins
• Cholesterol
– Cytoplasm
• Everything within the cell membrane except for
– Nucleus
• Contains hereditary information
Cell Membrane
• outer limit of cell
• controls what moves in and out of cell
• selectively permeable
•phospholipid bilayer
• water-soluble “heads” form surfaces
• water-insoluble “tails” form interior
• permeable to lipid-soluble substances
• cholesterol stabilizes the membrane
• proteins
• receptors: receive information
• pores, channels, carriers: allow materials to pass through
• enzymes: speed up chemical reactions
• CAMS: cell adhesion molecules
• self-markers: ID the cell as part of the organism
3-4
Cell Membrane
3-5
• The Fluid mosaic model
– The components of the cell membrane are all
moving randomly, switching positions
Intercellular Junctions
Tight junctions
• close space between cells
• located among cells that form
linings
Desmosomes
• form “spot welds” between cells
• located among outer skin cells
Gap junctions
• tubular channels between cells
• located in cardiac muscle cells
3-6
Cell Adhesion Molecules
• guide cells on the move
• selectin – allows white blood
cells to “anchor”
• integrin – guides white blood
cells through capillary walls
• important for growth of
embryonic tissue
• important for growth of nerve
cells
3-7
Movements Into and
Out of the Cell
Passive (Physical) Processes
• require no cellular
energy
• simple diffusion
• facilitated diffusion
• osmosis
• filtration
Active (Physiological) Processes
• require cellular energy
• active transport
• endocytosis
• exocytosis
• transcytosis
3-14
Simple Diffusion
• movement of substances from regions of higher concentration
to regions of lower concentration
• oxygen, carbon dioxide and lipid-soluble substances
3-15
Facilitated Diffusion
• diffusion across a membrane with the help of a channel or
carrier molecule
• glucose
3-16
Cells and Solutions
• Cells have many materials dissolved in
their cytoplasm, as does the
extracellular environment around the
cell. Water may move in or out of the
cell in response to the concentration of
these materials, called solutes. Nature
works to dilute solutions by moving
water where there is a high
concentration of solute and low water in
comparison to an adjacent area.
Solutions
• Solvent: does the dissolving
– usually water in living things
• Solute: gets dissolved in the solvent
– can be just about anything, but common
ones include
• Salts
• Ions
• sugars
Tonicity
• Hypertonic: when the solute
concentration is higher than the
surrounding environment
• Hypotonic: when the solute
concentration is lower than the
surrounding environment
• Isotonic: when the solute concentration
is the same as the surrounding
environment
Osmosis
• movement of water through a selectively permeable
membrane from regions of higher concentration to
regions of lower concentration
• water moves toward a higher concentration of
solutes
3-17
Cells and Solutes
(a)A cell is placed in a hypertonic solution; cell
shrinks
(b)A cell is placed in a hypotonic solution; cell
swells
Osmosis & Pressure
Osmotic Pressure – ability of osmosis to generate enough
pressure to move a volume of water
Osmotic pressure increases as the concentration of nonpermeable
solutes increases
• hypertonic – higher osmotic pressure
• hypotonic – lower osmotic pressure
• isotonic – same osmotic pressure
3-18
Tonicity and RBCs
hypertonic – higher osmotic pressure: cells shrink
isotonic – same osmotic pressure: cells remain the same
size
hypotonic – lower osmotic pressure: cells swell
Filtration
• smaller molecules are forced through porous membranes
• hydrostatic pressure important in the body
• Ex: molecules leaving blood capillaries
3-19
Active Transport
• carrier molecules transport substances across a membrane
from regions of lower concentration to regions of higher
concentration
• sugars, amino acids, sodium ions, potassium ions, etc.
3-20
Endocytosis
• cell engulfs a substance by forming a vesicle around the
substance
• three types
• pinocytosis – substance is mostly water
• phagocytosis – substance is a solid
• receptor-mediated endocytosis – requires the
substance to bind to a membrane-bound receptor
3-21
Endocytosis
3-22
Exocytosis
• reverse of endocytosis
• substances in a vesicle fuse with cell membrane
• contents released outside the cell
• Ex: release of neurotransmitters from nerve cells
3-23
Transcytosis
• endocytosis followed by exocytosis
• transports a substance rapidly through a cell
• Ex: HIV crossing a cell layer
3-24
Questions you must answer. You
may use the transport mechanisms animations on the Bio II page to do
so. When asked to compare and contrast, things you may want to think
about include: Think in terms of types of materials involved (size,
polarity, etc), energy (ATP) use, and how things get in/ out of the cell
(protein channels and the types of channels vs. using the membrane
itself).
• Answer these questions in the appropriate
place in your notes packet.
PowerPoint Lecture Outlines
to accompany
Hole’s Human
Anatomy and Physiology
Tenth Edition
Shier w Butler w Lewis
Chapter 3: Part II
Organelles
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
3-1
Endoplasmic Reticulum
Endoplasmic Reticulum
• connected, membrane-bound
sacs, canals, and vesicles
•Connected to nucleus
•Communicate with the cell
membrane
• transport system
3-8
(ER)
•rough ER
• studded with ribosomes
• protein and lipid synthesis
• smooth ER
• lipid synthesis
• break down of drugs
•Break down of lipids
•Cell with many ER would be
those responsible for making
proteins, as well as those that are
used to break down drugs
•Products of ER used to make
new cell membrane pieces
3-8
Ribosomes
• free floating or
connected to ER (rough
ER)
• site of protein synthesis
(link AAs to form
proteins)
•Made from proteins and
RNA (rRNA)
3-8
Golgi Apparatus/ Bodies
• group of flattened,
membranous sacs
(cisternae)
•Connect to the ER (which
coming out of the nucleus)
• packages and modifies
proteins (adds
carbohydrates, lipids etc as
needed)
3-9
Golgi
•Pieces bud off and become vesicles that can release
contents to the cell (vesicle trafficking) or outside of the
cell (secretory vesicles that break out)
•Common in white blood cells and liver cells, or those that
make protein hormones (like insulin)
3-9
Golgi
•Pieces bud off and become
vesicles that can release
contents to the cell (vesicle
trafficking) or outside of
the cell (secretory vesicles
that break out)
•Common in white blood
cells and liver cells, or those
that make protein
hormones (like insulin)
3-9
Mitochondria
•membranous sacs with inner
partitions
• generate energy by making
ATP from sugars and oxygen
(from the foods we eat as well
as the air we breathe)
•“Powerhouse” of the cell
3-9
Mitochondria
• double membrane bound
structure
•Inner membrane folds are the
cristae, which have enzymes on
them and control the chemical
reactions that release energy
(ATP)
•The stuff in between the fold is
the matrix
3-9
Mitochondria
•Have own DNA
•Get mitochondrial DNA from mom only
(mitochondrial Eve- tracing ancestors)
•Possible once a primitive cell
Resemble bacteria
? Bacteria taken into cells?
Typical cell has 1700 mitochondria; more in
cells that need a lot of energy (like muscles)
3-9
Lysosomes
Lysosomes
• enzyme-containing sack
•Sack of membrane
• digest worn out cell parts or unwanted
substances by using enzymes (40 types,
at least)
•Called the “suicide sack” because
breaking it open would digest cell
contents
3-10
Peroxisomes
Peroxisomes
• sacks of phospholipid membrane
•break down organic molecules (like drug, alcohol, or
food molecules) by using enzymes
•Peroxidases- make hydrogen peroxide (H2O2)
when breaking down molecules
•H2O2 is destructive to cells so must be
removed
•Catalase- breaks down hydrogen peroxide
•40 other types
•Abundant in liver
3-10
Centrosomes
Centrosome
• two rod-like centrioles (made from proteins)
• used to produce cilia and flagella
•distributes chromosomes during cell division
(mitosis) in animal cells
3-10
Cilia
Cilia
• short hair-like projections
• propel substances on cell
surface
•In respiratory tract
(Smoker’s cough)
•Lining of fallopian tubes
to propel egg
•In bacteria, they move the cell
around
3-11
Flagellum
Flagellum
• long tail-like projection
•Made from microtubules
• provides motility to sperm
Animation link 1
Animation link 2
3-11
Vesicles
Vesicles
• membranous sacs (phospholipid
membrane) formed from
•Pinched in pieces of cell membrane
•Pieces of Golgi or ER that have broken
off
• store substances (can be just about
anything- water, nutrients, enzymes, other
proteins or substances that the cell has
made)
3-12
Microfilaments
and Microtubules
Microfilaments (smaller) and
microtubules (larger)
• thin rods and tubules of
protein
• support cytoplasm
•Give shape, structure
• allows for movement of
organelles (pull organelles
around- like “ Mr. Gadget
arms”
•Important during mitosis/
meiosis
•animation
3-12
Inclusions
Inclusions
•Chemicals in the cytoplasm
•Stored nutrients
•Glycogen, lipids
•Temporary- will go in or out over
time
•Ex: melanin in skin- a tan goes
away over time
3-12
Cell Nucleus
• control center of cell;
involved with directing the
cell when to make certain
materials (usually
proteins)
•Surrounded by a
• nuclear envelope
• porous double membrane
•(phospholipid with over 1000 types of proteins)
• separates nucleoplasm from cytoplasm
•Allows mRNA out to make proteins (translation)
•Controls entry into and exit out of the nucleus
3-13
Cell Nucleus
• nucleolus (little nucleus)
• dense collection of RNA and
proteins
•At least one per nucleus
• site of ribosome production
•Larger if protein making cells
•Nucleoplasm
•The goo that is in the nucleus and
nucleolus
3-13
Cell Nucleus
• chromatin
(colored
substance)
• fibers of DNA and
proteins (histones)
•Look like “beads on
a string”
• stores information
for synthesis of
proteins
3-13
• First animation
• From the nucleus to the golgi bodies
• Overall cell review of organelles
Links to animations, ect
Diffusion links:
•
http://www.biosci.ohiou.edu/introbioslab/Bios170/diffusion/Diffusion.html
Osmosis Links:
• http://zoology.okstate.edu/zoo_lrc/biol1114/tutorials/Flash/Osmosis_Animation.htm
•
http://lewis.eeb.uconn.edu/lewishome/applets/Osmosis/osmosis.html
Interactive cellular transport:
•
http://www.wiley.com/legacy/college/boyer/0470003790/animations/membrane_transport/membrane
_transport.htm
•
http://www.connect.ab.ca/~lburns/students_tenunit2note.html
Interactive tutorial/ Quizzes
•
http://science.nhmccd.edu/biol/osotutor.html
Cell links…
• Cell structure:comparisons between cell types
http://www.wiley.com/legacy/college/boyer/04700
03790/animations/cell_structure/cell_structure.ht
m
• Cell structure and function http://www.wisconline.com/objects/index.asp?objID=AP11403
(right click on the here to start, and select play)
Just some good animation links
• http://www.stolaf.edu/people/giannini/biolo
gical%20anamations.html
• http://science.nhmccd.edu/biol/bio1int.htm