Question

1. water moves across cell membranes through special protein channels called—

a. vesicles

b. ribosomes

c. aquaporins

d. vacuoles

Explanation:

To solve this, we analyze each option:

• Option a: Vesicles are for transporting materials in cells, not water channels.
• Option b: Ribosomes are for protein synthesis, not related to water movement.
• Option c: Aquaporins are specialized protein channels that facilitate water movement across cell membranes.
• Option d: Vacuoles are storage organelles, not water channels.

Answer:

c. aquaporins