Water molecules and small ions enter a cell through
A)channels formed by integral proteins.
B)peripheral proteins.
C)lipid channels.
D)peripheral carbohydrates.
E)defects in the lipid layer of the membrane.

Question

Quizplus · Accepted Answer

Channels formed by integral proteins, also known as transmembrane proteins, allow water molecules and small ions to enter the cell. These channels create a pathway through the hydrophobic region of the lipid bilayer, which would otherwise repel these hydrophilic molecules. Peripheral proteins, lipid channels, and peripheral carbohydrates do not typically form channels or pores for water and ions to pass through. Defects in the lipid layer of the membrane could potentially allow for the entry of water and ions but are not a reliable mechanism for cellular uptake.

Water Molecules and Small Ions Enter a Cell Through