Lipids - Plasma Membrane

Question 1

What determines the fluidity of the cell membrane?

Answer 1

1. Chain length (Shorter chains INCREASE fluidity. Reduces tendency of chains to interact)
2. % of unsaturated fatty acids (More unsaturated fats INCREASE fluidity)

Question 2

What are the two modes of movement of lipids in the bilayer?

Answer 2

1. Lateral diffusion (FAST)

2. Transverse diffusion (SLOW)

Question 3

How do proteins move within the plasma membrane?

Answer 3

Lateral diffusion

Question 4

What molecules are permeable to the plasma membrane?

Answer 4

Hydrophobic (non-polar) molecules

Question 5

What are the two types of transport protein?

Answer 5

1. Channel proteins (does NOT change shape)

2. Carrier proteins (DOES change shape)

Question 6

What is the structure of Adenosine Triphosphate (ATP)?

Answer 6

1. Ribose (sugar)
2. Adenine (nitrogenous base)
3. 3 phosphate groups