2.2 Cell Membrane structure C

Question 1

What components make up a phospholipid?

Answer 1

1) Phosphate group - hydrophillic
2) 2 fatty acid tails - hydrophobic

Question 2

Describe the features of the phosphate head

Answer 2

It is polar, this means that it interacts with polar water molecules
- This can be described as HYDROPHILLIC
- These face towards the water

Question 3

Describe the features of the fatty acid tails

Answer 3

They are non polar, so it cannot interact with polar molecules like water
- This can be described as HYDROPHOBIC
- These face out of the water

Question 4

How does the phospholipid bilayer form?

Answer 4

• Hydrophilic heads face into the water
• Hydrophobic tails face out of the water
  EG: water O– –O outside of the cell
  water O– –O outside of the cell
  water O– –O outside of the cell

Question 6

How to identify polysaccharides attached to the membrane?

Answer 6

• Glycolipid - attached to the bilayer in a branch
• Glycoprotein - attached to protein

Question 7

What is the function of cholesterol in the plasma membrane

Answer 7

• fits in between phospholipids
• makes the membrane rigid
• at higher temperatures the membrane becomes more fluid