10. Transport III ppt

Question 1

What are the two types of transport across cell membranes?

Answer 1

Passive Transport and Active Transport

Question 2

What is Active Transport?

Answer 2

The movement of molecules across a cell membrane from a region of lower concentration to a region of higher concentration, against a gradient.

Question 3

What are the two types of Active Transport?

Answer 3

Primary Active Transport and Secondary Active Transport

Question 4

What is Primary Active Transport?

Answer 4

Transport that is conjugated with ATP hydrolysis or light energy

Question 5

What is the role of ATP in Primary Active Transport?

Answer 5

ATP hydrolysis provides energy for the transport process.

Question 6

What are P Pumps?

Answer 6

E1 and E2 ATP-ases involved in primary active transport.

Question 7

What are F and V pumps?

Answer 7

F0F1 and V0V1 ATP-ases involved in primary active transport.

Question 8

What are ABC Transporters?

Answer 8

A family of proteins that transport various molecules across cell membranes using ATP.

Question 9

What is the function of the Sodium-Potassium Pump?

Answer 9

Pumps 3 sodium ions out of cells and 2 potassium ions into cells, both against their concentration gradients.

Question 10

What is an electrogenic pump?

Answer 10

A primary active transporter that creates a net charge difference across the membrane.

Question 11

What is the net charge change produced by the Sodium-Potassium Pump?

Answer 11

+1 net charge outside the cell and -1 charge inside the cell.

Question 12

What are the basic functions of the Na+/K+-ATPase?

Answer 12

• Maintain resting potential
• Regulate osmotic balance
• Control cellular volume

Question 13

What are the two subunits of the Na+/K+-ATPase?

Answer 13

Alpha subunit and Beta subunit

Question 14

What is the approximate size of the alpha subunit of Na+/K+-ATPase?

Answer 14

~113 kD

Question 15

What is the role of the beta subunit in Na+/K+-ATPase?

Answer 15

Necessary for the activity of the complex and facilitates the localization and activation of the alpha subunit.

Question 16

How many transmembrane domains does the Na+/K+-ATPase likely possess?

Answer 16

8 or 10 transmembrane domains

Question 17

What triggers the conformational changes in the Na+/K+-ATPase during cation transport?

Answer 17

Phosphorylation of the pump

Question 18

What is the function of the gastric H+ Pump?

Answer 18

Exchanges 1 H+ for 1 K+ and acidifies stomach contents.

Question 19

What drugs inhibit the gastric hydrogen potassium ATPase?

Answer 19

Omeprazole and Lansoprazole

Question 20

Where is the H+/K+ ATPase primarily found?

Answer 20

In parietal cells of the gastric mucosa

Question 21

What do CPx ATP-ases transport?

Answer 21

Heavy metal ions like Cu2+ and Cd2+

Question 22

What diseases are associated with mutations in CPx ATP-ases?

Answer 22

• Menkes disease
• Wilson’s disease

Question 23

What is Secondary Active Transport?

Answer 23

The active transport of ions/substrates that is energetically driven by the passive transport of another ion/substrate.

Question 24

What are the three types of transport in Secondary Active Transport?

Answer 24

• Symport
• Antiport
• Uniport

Question 25

What is a uniporter?

Answer 25

An integral membrane protein involved in facilitated diffusion, transporting one molecule at a time.

Question 26

What is a symporter?

Answer 26

An integral membrane protein that transports multiple differing types of molecules across the membrane in the same direction.

Question 27

What is an antiporter?

Answer 27

A cotransporter that moves two or more different molecules or ions across a membrane in opposite directions.