Cell Membrane

Question 1

Cell membrane

Answer 1

Perméable, as some small molecules diffuse through cell membrane, some substances dissolve in lipid layer. Some also pass through special proteins.

Question 2

Roles of surface off cell

Answer 2

Separate cell component from external environment.
Regulate transport.
Antigens.
Release chemicals- to signal others.
Communicate via receptors.
Site of reactions. ``

Question 3

Within cell

Answer 3

Divide cell to organelles
Form vesicles to transport substances
Control, enter leave orangelle,
Give surface area

Question 4

The fluid mosaic model

Answer 4

1972.
Phospholipid form bilateral, as move.
Chloresterol within bilateral.
Proteins scattered like mosaics.

Question 5

Phospholipids

Answer 5

Head-hydrophilic
Tail-hydrophotbic.

Heads are towards water, centre dosent allow water soluble to come through

Question 6

Cholestérol

Answer 6

Fit between phopsholids, binds to tail, so less fluidity, more rigid.
Low temp-not close=more fluidity 1

Question 7

Proteins

Answer 7

Controls coming in out.
Channels-charged/small to go through.
Career proteins-transport molecules-diffusion
Receptors-cell signalling

Question 8

Glycoproteins/glyolipids

Answer 8

Stabilise memebrane, form h2 bonds with water.
Drugs,hormones,antibodies bind
Receptor for cell signalling.

Question 9

Diffusion

Answer 9

Net movement of particles from high concentration to low concentration

Question 10

Active transport

Answer 10

Energy, moving from low concentration to High conc