4. Biological Membrane Structure

Question 1

What are the functions of the cell membrane?

Answer 1

Physical barrier
Transportation
Receptors to stimuli
Structural support

Question 2

Phosphate group + serine

Answer 2

Phosphatidylserine

Question 3

Phosphate group + ethanolamine

Answer 3

Phosphatidylethanolamine

Question 4

Phosphate group + choline

Answer 4

phosphatidylcholine (lecithin)

Question 5

Phosphate group + inositol

Answer 5

Phosphatidyllinositol

Question 6

What types of sphingolipids can be found in the cell membrane?

Answer 6

Sphingomyelins
Cerebosides
Gangliosides

Question 7

What is the function of cholesterol within the cell membrane?

Answer 7

Modulates fluidity

Question 8

What is the meaning of the fluid mosaic model?

Answer 8

Plasma membrane is a mosaic of components that move around freely and fluidly in the plane of the membrane

Question 9

Name 3 forms of integral proteins

Answer 9

Single alpha helix
Multiple alpha helices
Beta sheet

Question 10

Name 4 forms of peripheral proteins

Answer 10

Alpha helix embedded in bilayer
Protein attached to lipid chain
Protein attached to phosphatidylinositol
Non covalent interaction between proteins

Question 11

What are the functions of membrane proteins?

Answer 11

Anchoring
Recognition
Enzymes
Receptors
Carrier proteins
Leak channels
Gated channels

Question 12

What complex molecules may carbohydrates be components of?

Answer 12

Proteoglycans
Glycoproteins
Glycolipids

Question 13

What are the functions of the glycocalyx?

Answer 13

Lubrication and protection
Anchor
Locomotion
Specificity in binding
Recognition

Question 14

Name 2 examples of primary active transport

Answer 14

Na/K pump

Hydrogen Potassium ATPase

Question 15

Name an example of secondary active transport

Answer 15

Na/glucose transporter

Question 16

Name an example of group translocation

Answer 16

Phosphotransferase system