AP BIOLOGY

Detailed explanation-1: -Carrier proteins and channel proteins are the two major classes of membrane transport proteins. Carrier proteins (also called carriers, permeases, or transporters) bind the specific solute to be transported and undergo a series of conformational changes to transfer the bound solute across the membrane (Figure 11-3).

Detailed explanation-2: -Many of these proteins are embedded into the membrane and stick out on both sides; these are called transmembrane proteins.

Detailed explanation-3: -Permeation of water across cellular membranes is facilitated by a family of membrane channels called aquaporins (AQP) (1–4).

Detailed explanation-4: -Carrier proteins bind specific molecules to be transported on one side of the membrane. They then undergo conformational changes that allow the molecule to pass through the membrane and be released on the other side.