2.1

Question 1

What is the function of the plasma membrane?

Answer 1

• Protection and communication
• Ensure cell structural integrity
• Regulated enters and exit of substances
• Participates in communication and enzymatic activities
• Maintains chemical composition of cytoplasm and extracellular fluid

Question 2

What are anchoring proteins?

Answer 2

• Attach plasma membrane to other structures and stabilise its position
• Inside the cell, membrane proteins are bound to the cytoskeleton

Question 3

What are recognition proteins?

Answer 3

• Detected by cells of the immune system.
• Enzymes in plasma membrane may be integral or peripheral proteins

Question 4

What are receptor proteins?

Answer 4

Bind to specific extracellular molecules called ligands.
A ligands can be anything from a small ion to a hormone

Question 5

What are carrier proteins?

Answer 5

Bind solutes and transport them across the plasma membrane.

Question 6

What are channels?

Answer 6

Integral proteins containing a central pore that forms a passageway completely across the plasma membrane.
The channel permits the passage of water and small solutes that cannot otherwise cross the lipid layer of the plasma membrane.

Question 7

What is the identification system?

Answer 7

Proteins anchored to the cell membrane
Presented on the outside surface
Cell markers.