Physiology I

Which of the following is the main mechanism by which glucose is absorbed in the small intestine?

• A. Simple diffusion
• B. Secondary active transport with sodium
• C. Facilitated diffusion with glucose transporter 4 (GLUT-4)
• D. Primary active transport with ATPase

In the sodium-potassium pump, which ions are transported and in which direction?

• A. 3 Na+ out, 2 K+ in
• B. 2 Na+ out, 3 K+ in
• C. 2 Na+ in, 3 K+ out
• D. 3 Na+ in, 2 K+ out

How does facilitated diffusion differ from simple diffusion?

• A. Facilitated diffusion requires ATP
• B. Facilitated diffusion requires carrier proteins
• C. Facilitated diffusion moves substances against their concentration gradient
• D. Facilitated diffusion is slower than simple diffusion

What happens to membrane potential when chloride ions move into a cell?

• A. The membrane potential becomes more positive
• B. The membrane potential remains unchanged
• C. The membrane potential becomes more negative
• D. The cell becomes depolarized

Which of the following ions is the most permeable in a resting nerve cell?

• A. Potassium (K+)
• B. Sodium (Na+)
• C. Calcium (Ca2+)
• D. Chloride (Cl−)

Which of the following best describes the mechanism of action of the sodium-glucose linked transporter (SGLT)?

• A. Uses the energy of the sodium gradient to transport glucose
• B. Uses ATP to transport glucose into the cell
• C. Transports glucose against its gradient without sodium involvement
• D. Transports glucose in exchange for sodium ions

Which of the following is primarily responsible for establishing the resting membrane potential?

• A. Voltage-gated sodium channels
• B. Leakage of potassium ions
• C. Active transport of calcium ions
• D. Inward movement of sodium ions

In which part of the nephron does the majority of sodium reabsorption occur?

• A. Distal convoluted tubule
• B. Proximal convoluted tubule
• C. Collecting duct
• D. Loop of Henle

Which of the following transport processes requires energy in the form of ATP?

• A. Primary active transport
• B. Facilitated diffusion
• C. Osmosis
• D. Simple diffusion

What type of transport mechanism is used by the proton pump in the stomach to secrete H+ into the lumen?

• A. Facilitated diffusion
• B. Primary active transport
• C. Secondary active transport
• D. Simple diffusion