Question

which of the following is a function of proteins in the cell membrane maintaining homeostasis?
they help transport materials in and out of cells
they provide a quick supply of energy to use for active transport
they store genetic information to provide directions for transport
they store energy for long - term use for later reactions

Explanation:

• For the option "They help transport materials in and out of cells": Cell membrane proteins (like channel and carrier proteins) facilitate the movement of substances (e.g., ions, nutrients) across the membrane, which is vital for maintaining homeostasis (e.g., regulating internal concentrations).
• For "They provide a quick supply of energy to use for active transport": Proteins do not act as an energy source; ATP provides energy for active transport.
• For "They store genetic information to provide directions for transport": DNA stores genetic information, not proteins.
• For "They store energy for long - term use for later reactions": Lipids (e.g., fats) and carbohydrates (e.g., glycogen) are more involved in long - term energy storage, not proteins.

Answer:

A. They help transport materials in and out of cells