Question

I. Large or charged molecules move with the concentration gradient.

II. Water moves against the concentration gradient.
III. Transport requires a membrane protein and ATP energy.
IV. A membrane protein is used to move molecules with the concentration gradient.
V. This is a form of passive transport.
VI. Small, nonpolar molecules move with the concentration gradient.

1. The prompt contains several characteristics of cell transport. Which of these applies to facilitated diffusion?
A) I only
B) I, IV, V
C) I, II, IV
D) II, III, V, VI

2) Which scenario is MOST likely to use facilitates diffusion for transport?
A) Water moves from high to low concentration.
B) Glucose moves into the cell from high to low concentration.
C) O2 diffuses from the alveoli into the blood stream, without the use of energy.
D) Na+ moves out and K+ moves into the cell against the concentration gradient.

Answer 1

Facilitated diffusion is a form of passive transport that allows molecules to move down their concentration gradient using specific protein channels in the cell membrane. It does not require energy and is used by molecules that cannot easily diffuse on their own, such as glucose and ions.

Step-by-step explanation:

Facilitated diffusion is a type of passive transport that allows certain molecules to move down their concentration gradient through specific protein channels in the cell membrane. It does not require energy and is used by molecules that cannot easily diffuse across the membrane on their own, such as polar molecules like glucose and ions. Water, on the other hand, moves by osmosis, which is the movement of water molecules across a semipermeable membrane from an area of higher concentration to an area of lower concentration. Therefore, facilitated diffusion applies to characteristics I, IV, and V of the given options.