Membranes And The Transport Process

Question 1

What do membranes do? (5)

Answer 1

Define the boundary of the cell; serve as sites for biochemical functions; provide transport for proteins; contain receptors for signalling; provide mechanisms for cell-to-cell contact

Question 2

Describe the polar nature of membranes.

Answer 2

Membranes have polar heads with non polar tails

Question 3

What are the characteristics of integral membrane proteins? (3)

Answer 3

Hydrophobic, very strong lipid interactions, hard to remove (require detergents)

Question 4

What are the characteristics of peripheral membrane proteins?(2)

Answer 4

Lack hydrophobic sequences, loosely attached.

Question 5

How can transport across a membrane happen? (2)

Answer 5

Passively via facilitated diffusion or actively via transport

Question 6

What is osmosis?

Answer 6

The diffusion of water across a semi permeable membrane

Question 7

What is simple diffusion?

Answer 7

The flow of molecules from an area of high concentration to an area of low concentration.

Question 8

What are the three types of transport?

Answer 8

Uniport (one in); symport (two in); antiport (one in, one out)