Multiple Choice
In the context of principles of transmembrane transport, which statement correctly distinguishes facilitated diffusion from active transport?
30
views
9. Transport Across Membranes
Principles of Transmembrane Transport
Multiple Choice
Which of the following is a form of active transmembrane transport?
A
Osmosis of water through aquaporins driven by an osmotic gradient
B
Facilitated diffusion of glucose through a GLUT transporter down its concentration gradient
C
Simple diffusion of across the lipid bilayer down its concentration gradient
D
/ ATPase pumping ions against their concentration gradients
Verified step by step guidance1
Understand the difference between passive and active transport: Passive transport moves substances down their concentration gradient without energy input, while active transport requires energy to move substances against their gradient.
Analyze each option to determine if it requires energy and moves substances against their concentration gradient:
Osmosis through aquaporins is passive because water moves down its osmotic gradient without energy.
Facilitated diffusion of glucose via GLUT transporters is passive since glucose moves down its concentration gradient without energy.
Simple diffusion of O\_2 across the lipid bilayer is passive as O\_2 moves down its concentration gradient without energy.
The Na\+/K\+ ATPase actively pumps Na\+ and K\+ ions against their concentration gradients using ATP, which is a classic example of active transmembrane transport.
Related Videos
Related Practice
