Cell membrane structures.

Question 1

describe the cell membrane

Answer 1

it covers every surface of the cell and it has a double layer, and it’s semi permeable

Question 2

what molecules diffusion faster into the cell membrane?

Answer 2

small and non polar molecules

Question 3

what is the fluid mosaic structure?

Answer 3

it describes the movement and structure of cell membranes - fluid because the proteins move/ mosaic because it has a mosaic like structure

Question 4

what are the four functions of the cell membrane?

Answer 4

1. keeps cellular components inside the cell
2. allows selected molecules to move into the cell
3. isolates organelles from the cytoplasm
4. forms a bilayer = acts as a barrier for the cell

Question 5

features of the cell membrane - phospholipid bilayer 2 points

Answer 5

the head is hydrophilic and the tail is hydrophobic

it acts as a barrier between the cell and it’s environment, as the centre of the bilayer is hydrophobic

Question 6

features of the cell membrane - glycoproteins - 3 points

Answer 6

• it’s a receptor molecule
• membrane stabilisation
• cell recognition

Question 7

features of the cell membrane - glycolipids `

Answer 7

• receptor molecule
• cell recognition
• cell signalling
• cell-cell attachment

Question 8

what does cholesterol do to the membrane?

Answer 8

it affects fluidity and maintains the shape of animal cells for cells that aren’t supported by other cells

Question 9

How does cholesterol make membranes less fluid?

Answer 9

the molecules fit between the phospholipids, so bind to the hydrophobic tails = closely packed together = restricting movement