Lecture 8 - Cell Transport B

Question 1

How do small non-polar molecules get inside cells?

Answer 1

Diffusion through the phospholipid bilayer

Question 2

How do small polar molecules get inside cells?

Answer 2

Membrane Transport Proteins

Question 3

How do large molecules get inside cells?

Answer 3

Exocytosis and Endocytosis

Question 4

What are examples of molecules transported by membrane transport proteins?

Answer 4

Amino Acids and Monosaccharides

Question 5

Where are membrane transport proteins located?

Answer 5

They are located in the plasma membrane of all cells

Question 6

Channel Proteins:
passive or active?
what molecules are transported?
does proteins change shape?

Answer 6

passive transport of Na+, K+, Cl- etc.
Protein doesn’t change shape.

Question 7

Passive Transporters:
passive or active?
what molecules are transported?
does proteins change shape?

Answer 7

Passive transport of amino acids, monosaccharides. The protein changes shape as the membrane moves and knocks it.

Question 8

Which are faster?
A. Channels
B. Passive transporters

Answer 8

A. Channels: not large enough for amino acids because water will leak (up to 1 million per second)
B. Passive Transporters: used for amino acid transport (up to 100 per second)

Question 9

ATP-powered transporters:
passive or active?
what molecules are transported?
does proteins change shape?

Answer 9

Active transport of ions, protein changes shape when energy provide

Examples: Proton pump, Sodium-potassium pump, H+ powered transporters, Na+ powered transporters

Question 10

Which one is passive/active?
A. SGLT
B. GLUT

Answer 10

SGLT: active
GLUT: passive