B1.1 cell membranes and B2.1 fluid mosaic model

Question 1

What distinguishes simple diffusion from facilitated diffusion?

Answer 1

The rate of facilitated diffusion depends on the number of transport proteins in the membrane, while simple diffusion does not.

Question 2

glucose cant get

Answer 2

through bilayer

Question 3

(pumped is

Answer 3

against concentration gradient

Question 4

membranes also contain

Answer 4

carbohydrates in addition to phospholipids and proteins

Question 5

the carbohydranes can be…… bonded

Answer 5

the carbohudrates (polar and extend to extracellular) can be covalently bonded to lipids (non polar), forming glucolipids

or glycoproteins if they are boned to proteins

Question 6

the carbohydrantes are ……..a

Answer 6

amphipathic and stuck to external surface of cell membranes

Question 7

Glycolipids are classified into:

Answer 7

Glycoglycerolipids (glycerol based lipids)

Glycosphingolipids (cerebrosides)

Question 8

glycolipids contribute to

Answer 8

They contribute to the membrane stability and form H bonds with the water molecules around the cell.

Question 9

the glycocalyx is the

Answer 9

is the sticky layer formed by the carb group of the glycolipids and glycoprotein that protrude the cell surface. This helps cell signalling, cell adhesion, cell-cell recognition and protects the cell surface.

Question 10

THE FLUID MOSAIC MODEL: says

Answer 10

Says the lipid bilayer is fluid and this fluidity depends on the nature of the fatty acids jn the phospholipid molecules and the amount of cholesterol.

And the proteins (intergal and peripheral) are embedded into the fluid bilayer which resemble a mosaic.

So most of the proteins and lipids can move parallel to the membrane surface.

Question 11

the cell membrane/lipid bilayer is shaped like a mosaic, cause

Answer 11

The integral and peripheral proteins

Question 12

where dp you have more info ab this

Answer 12

word