Cell surface membrane

Question 1

What is the membrane of a cell made out of?

Answer 1

1. Phospholipids (phosphate head + lipid tail)
2. Extrinsic proteins (glycoproteins)
3. Intrinsic proteins (channel/carrier proteins)
4. Carbohydrates (glycoproteins and glycolipids)
5. Cholesterol

Question 2

1. What is able to pass through the phospholipid bilayer via ordinary diffusion/osmosis?
2. Give some examples.

Answer 2

1. Small, non-polar molecules. Lipid-soluble molecules. Water on its own is an exception due to its small molecule size.
2. Oxygen, Carbon Dioxide, Water (on its own)

Question 3

1. What isn’t able to pass through the phospholipid bilayer via ordinary diffusion/osmosis?
2. Give some examples.

Answer 3

1. Larger & polar molecules (with exception of water).

2. Ions, water with dissolved things (e.g. cytoplasm or blood plasma/blood)