Transcript Plasma Membrane - Rapid City Area Schools

Warm-up 2/22/11
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Teach the Teacher: What is
something going on in the news?
Review: What is homeostasis?
Learning Target: What is one part of
the cell that helps it maintain
homeostasis? Cells have what kind of
things in it?
Flash Card
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On the Front:
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Homeostasis
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On the Back:
Balance, keeping
equilibrium
(98.6degrees body)
Warm-up 2/24/12
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Teach the Teacher: If you could
travel to any city in the US where
would you want to travel and why?
Review: If I was testing to see what
kind of anti-persperant worked the
best, what would be the dependent
variable?
Learning Target: Compare cell
organelles to a city.
Flash card
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On the front:
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 Ribosome
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On the Back:
Circles of protein
synthesis
Flash card
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On the front:
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Mitochondria
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On the Back:
Creates energy for
the cell (folded
membrane)
Travel Brochure for A cell
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Using small roadside attractions as an
inspiration, you will produce a travel
brochure to entice visitors to take the next
exit and visit the "incredible!, amazing!, and
unbelievable!" sights of an animal or plant
cell. For example, visitors might want to
"visit the ribosomes, located just outside the
nucleus, and watch as proteins are
synthesized RIGHT BEFORE YOUR VERY
EYES!".
Warm-up 3/1/12
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Teach the Teacher: What is the worst
you have ever hurt yourself or the
sickest you have ever beenhospitalization, etc. that you care to
share.
Review: Which organelle makes
proteins for the cell.
LT: Identify the functions of 4 cell
organelles
The Ultra-Structure of
Animal Cells
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Draw a sketch and give one fact for
each organelle:
Cell Membrane
Golgi Body and Vacuole
Mitochondrion
Centriole
Cell Organelle Quiz
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1. What organelle provides energy for
the cell?
2. List 4 other organelles AND their
function (plant or animal)(can’t use
#1).
3. What is the main “export” of the
cell? (like the widget in the city)
4. What is the part of an experiment
that changes?
Warm-up 3/7/12
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Teach the Teacher: What is your
favorite Saturday morning cartoon?
Review: List as many organelles as
you can…
Lt: Describe the function of the plasma
membrane
The Homeostasis
Regulator….Plasma
Membrane!
Review
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Cell theory: all living things come from
pre-existing cells
Homeostasis: maintaining balance in
an organisms internal environment
 HOMEOSTASIS
IS ESSENTIAL
TO SURVIVAL!!!!!!
Plasma Membrane
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Made of 2 groups
of organic
molecules:
phospholipids
and proteins
Phospholipids:
molecules
shaped like a
head with 2 tails
Plasma Membrane
Polarity
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Heads are the
phosphorous
group which are
polar (attract
H2O)
Tails are long
lipid chains that
are non-polar
(push H2O away)
PM: like a sandwich
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Polarity of the
phospholipids
causes them to
form a 2 layer
“sandwich”
Prevents most
materials from
passing in/out of
cell
The other stuff
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Proteins are
embedded in the
bilayer
3 types: Marker
proteins (curley-q)
identify the cell as
to type
Receptor proteins
gather info about
the cell’s
surroundings
Channel proteins
act as the
“gatekeeper” of the
cell allowing larger
molecules in/out of
the cell
Passive & Active Transport: Moving
Materials across the Plasma
Membrane
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First a chemistry
review:
Solute is the substance
that dissolves in
another substance
Solvent is the more
plentiful substance that
dissolves the solute
Mixture of solute and
solvent= solution
Passive
Transport
Does NOT involve the use of
Energy to bring things in/out
of cell
Molecules seek homeostasis
between the inside/outside
of cell using the
concentration gradient
The Power Behind Passive
Transport
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Diffusion: when substances move from
an area of higher concentration to an
area of lower conc.
Example: O2 in your blood stream
Osmosis: diffusion of H2O molecules in
the direction of higher solute
conconcentration (if solute is high then
H2O is low)
Social-Scientific Issue
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An issue that relates to science that is
affected by:
– Politics
– Economics
– Morality
– Human Health
P M and 3 solutions
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Hypertonic solution: solute concentration
Out of the cell is higher than in the cell
(more H2O molecules in the cell)
H2O molecules rush out of the cell to area of
lower H2O conc.
Causes cell to shrivel
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Hypotonic solution: solute concentration
out of the cell is lower than in the cell
(more H2O out of cell)
H2O molecules rush into the cell
Cell swells and can explode!
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Isotonic solution: solute conc. is the same
inside of the cell as outside of the cell
Equal amounts leave/enter the cell to
create homeostasis
Cell stays the same size
This is what they give you in an IV to
rehydrate you
One more thing about
diffusion……….
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Facilitated diffusion is when the plasma
membrane is selectively permeable—it is
choosy about what it lets into the cell
Channel protein does the choosing
“Regular” diffusion and osmosis do not involve
the channel proteins
Still does not use E
Active Transport
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Cell uses E to actively bring substances
into the cell against the concentration
gradient
Doesn’t matter if there is MORE of that
substance in the cell—if the cell wants
more it uses E to get more!
Plants use proton pumps to pump H atoms that
are missing their electrons (hence the name )
through the internal membranes of
mitochondria and chloroplasts for E production
(Krebs cycle)
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Animals use sodium-potassium pumps to pump
Na out of the cell and K into the cell
Na bonds with a glucose molecule while it is
outside and then is pumped back into the cell
Glucose is released inside the cell and then Na
leaves on another trip through the pumps
Nerve cells use the differences in Na and K
conc. Caused by these pumps to send signals
across the synapses thru-out the body
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When food particles are too big to
be brought thru the channel
proteins, the cell will engulf the
particle
This is called endocytosis
Pinocytosis is when a liquid w/
dissolved molecules are brought
in
Exocytosis is how wastes are
discharged from the cell in
vacuoles; can also secrete
chemical products (hormones)
Phagocytosis is when another
cell or part of a cell is brought in;
WBC “eat” invading bacteria, or
amoebas devour their prey in this
manner
Warm-up 10/12/11
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Teach the Teacher: What would be
the best way to motivate students in
school?
Review: What are the macromolecules
that make up cells (there are 4)
Learning Target: Eukaryotic cells have
what kind of things in it?
Flash Card
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Osmosis
Diffusion
Phospholipid
bylayer
Plasma
cell/membrane
Trash Basketball
Which one is a
phospholipids? (makes up
the plasma membrane)
Because the
phospholipids tails are
hydrophobic the plasma
membrane looks like a
This does not require
energy…
This is the brain of the
cell
Diffusion is when a
substance goes from a ____
to a _____ concentration
What would be the
solvent?
This organelle makes
proteins
Warm-up 10/13/11
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Teach the Teacher: If you could give a
million dollars to a charity, what
charity would you give it to?
Review: Name as many different parts
of the inside of a cell as possible
Learning Targets: How osmosis and
diffusion worked in the egg lab,
different cells in the body, plant vs.
animal cells