Question

GLUT transporters show:

• A. \( \text{Facilitated diffusion} \)
• B. \( \text{Active transport} \)
• C. \( \text{Endocytosis} \)
• D. \( \text{ATP dependence} \)

Hint:

GLUT4 is the specific transporter that is sensitive to insulin, moving to the cell surface only when insulin is present.

Answer 1

The Correct Option is A

Concept: Glucose is a polar molecule and cannot easily pass through the hydrophobic lipid bilayer of cell membranes.
• Cells use specialized proteins called GLUT (Glucose Transporters) to move glucose.
• There are two main types of glucose transport: Active and Passive.

Step 1: Mechanism of GLUT Transporters.
GLUT transporters are a family of carrier proteins that move glucose down its concentration gradient. Since the movement is from high concentration to low concentration, no cellular energy (ATP) is required.

Step 2: Categorizing the Transport.
Passive transport mediated by a protein carrier is called "Facilitated diffusion." The GLUT protein undergoes a conformational change to "flip" the glucose from one side of the membrane to the other. This is distinct from the SGLT transporters, which use active transport. Final Answer: GLUT transporters operate via the process of Facilitated diffusion.