Download 1.4.1: Draw a diagram of the fluid mosaic model:

1.4.1: Draw a diagram of the fluid mosaic model:
• Show bilayer, cholesterol, glycoprotein, integral and
peripheral proteins.
Peripheral
hydrophilic
Hydrophobic
proteins
are on the
outside
layer…
just draw
one…
(Integral protein)
hydrophilic
1.4.2: Label the hydrophobic and hydrophilic portions and
explain how phospholipids maintain the structure of cell
membranes.
Phospholipids have a polar ‘head’ (phosphate group) and a non-polar
hydrocarbon chain. Polar likes water and is near the water. The nonpolar lipid chains stay together away from the water.
6
Name A, B, C, D, E
A
E
B
C
D D
7
What is
A = Glycoprotein
B = Cholesterol
C = Peripheral protein
D = Integral or trans-membrane
E = Glycolipid?
16
Part A
Part B
Which is hydrophobic? Which is hydrophilic?
17
Part A is hydrophilic and polar
Part B is hydrophobic and non-polar
18
Name 4 functions of membrane proteins.
19
What is
•hormone binding (allows hormones to bind)
•Enzyme action (Really CAUSES a reaction! Like in addiction,
when a drug binds to a membrane protein, it causes an enzyme
reaction within the cell –neuron.)
•Channels or openings for facilitated diffusion
•Anchoring
•Active transport –use ATP to get material into or out of the cell..
20
Integral proteins have to be hydrophobic in the areas of the
membrane that are hydrophobic and hydrophilic in the areas of the
membrane that are hydrophilic. What part of the amino acid (in the
chain of amino acids that make a protein) is able to change to be
polar or nonpolar?
21
What is the ‘R’ group?
Glycoproteins and glycolipids are
used in cell recognition.
Movement into the membrane:
Gasses move easily… charged things or things that are large?
Nope…
Carrier proteins can move charged or
big things into the cell!
If moving the item requires energy it is
called active transport. If it doesn’t require
energy it is called facilitated diffusion.
???
Question!
• When does the cell use active transport?
Used to stockpile something
• When does the cell use facilitated diffusion?
– When we want to let something slide on
through…
Why do we ever want to put a bunch of ions on one
side of a membrane? Well, we can force them
through one special membrane protein and make
ATP in chemiosmosis…We will cover chemiosmosis
later… (chemical osmosis.)
Endocytosis (‘Enter cell’) and Exocytosis (‘Exit cell’)
Exocytosis! (Pretty dang cool.)
Phagocytosis:
endocytosis
where the
membrane wraps
around the
desired material
and ‘eats’ it.
Phago=eat
Phagocytosis pictures
Pinocytosis:
endocytosis
where the cell
‘drinks’.
Pino=drink
Pinocytosis = Cell drink
Cotransport
proteins: