The Cell Membrane
Why is the job of the cell membrane so
important for the cell?

Turn to your partner and talk about
these reasons.
 Who
would like to report out your
thoughts.
 What
does the membrane look like,
draw it
Homeostasis: an organisms ability to
maintain an internal stable environment.
How is cell membrane transport vital to an
organisms homeostasis?
Within your group draw what you remember to be the
structure of the membrane
1. What will go in and out of the cell
2. Are there any regulators to enforce what goes in or out?
3. If homeostasis is maintaining a stable internal
environment, what role does the cell membrane play?
“Water loving”
“Water disliking”
THE CELL MEMBRANE
Review terms
Integral protein: embedded protein spanning from 1
end of bilayer to the other. Help ions and molecules travel into
the cell.
What’s the difference
between the two?
Locate these on your
membrane and label
them
Review
Peripheral protein: sit on outside of cell and
are connected to integral proteins as well as
cytoskeleton filaments and aid in support
Locate them on your membrane and label them.
Review
Glycoprotein: protein and carbohydrate
Protein is connected to cell membrane
Carbohydrate: cell recognition and receptors
functions: cellular recognition, immune responses and
receptors for hormones and neurotransmitters
Which is the protein?
Find it on your
membrane and label it
Review
Cholesterol: embedded within the fatty acid
chains in phospholipids. Helps to maintain
fluid condition and the C-H tails from
sticking together.
What else do we know
about cholesterol?
Review
Cytoskeletal filaments: Attached to the cell membrane on the
inside of the cell. They help aid with support to the cell.
1.Label them on your
membrane.
2. Identify the inside and
outside of the cell on you
Membrane model.
Let’s review all the parts!
OUTSIDE CELL
CARBOHYDRATE
GLYCOPROTEINS
Or glycolipids
PHOSPHOLIPID BILAYER
CHOLESTEROL
Peripheral
protein
Integral
PROTEIN
Integral PROTEIN INSIDE CELL
Channel
protein
FLUIDITY MODELS
Before bubble lab
https://www.youtube.com/watch?v=Rl5EmUQdkuI
After bubble lab
http://www.dnatube.com/video/68/Membranefluidity
Rate of Diffusion

Set up 3 beakers: hot water, cold water, other

Add 50 ml of each liquid into the beaker

Add 2 drops of food coloring approximately at the
same time and start timer

Look for the food coloring to completely diffuse
throughout the beaker

Record time
substance