What type of proteins are situated in the cell membrane and act as channels?

Transport proteins are specifically designed to facilitate the movement of substances across the cell membrane. These proteins play a crucial role in regulating the entry and exit of ions, nutrients, and other molecules, ensuring that the cell maintains homeostasis. They function as channels or carriers that allow selective passage, often utilizing mechanisms like facilitated diffusion or active transport to move substances according to the cell's requirements.

Enzymatic proteins, while also vital, primarily catalyze biochemical reactions within the cell rather than acting as a conduit for transport. Structural proteins contribute to the shape and integrity of the cell and its components, rather than directly moving substances across the membrane. Storage proteins serve as reservoirs for amino acids or other nutrients but do not have a role in the transport process across the membrane. This distinction highlights the unique function of transport proteins in cellular processes.