Indicate three functions of proteins in the cell membrane.
Check all that apply.
A. Receptors to bind to chemicals
B. Provide nutrients for the cell
C. Adhere adjacent cells to each other.
D. Channel for ions to move through
E. Cell division
The Correct Answer and Explanation is :
Correct Answer:
A. Receptors to bind to chemicals
C. Adhere adjacent cells to each other
D. Channel for ions to move through
Explanation:
Proteins in the cell membrane perform essential roles that support the structure and functionality of cells. Here is how the selected options fit their functions:
- Receptors to bind to chemicals (A):
Membrane proteins serve as receptors that allow the cell to communicate with its environment. These receptors bind to specific signaling molecules, such as hormones or neurotransmitters, initiating a cellular response. For example, insulin binds to its receptor protein on the cell membrane to regulate glucose uptake. This process is crucial for cellular signaling and maintaining homeostasis. - Adhere adjacent cells to each other (C):
Some membrane proteins function as adhesion molecules, helping cells stick together and form tissues. These proteins, like cadherins and integrins, establish strong connections between neighboring cells and the extracellular matrix. This adhesion is vital for the structural integrity of tissues and plays a role in processes such as wound healing and immune responses. - Channel for ions to move through (D):
Channel proteins facilitate the movement of ions across the cell membrane, a process critical for cellular functions like generating electrical signals in neurons and maintaining ionic balance. For instance, ion channels allow sodium (Na+), potassium (K+), calcium (Ca2+), and chloride (Cl-) to pass through the membrane selectively. This transport is vital for nerve conduction, muscle contraction, and maintaining the resting potential of cells.
Incorrect Options:
- Provide nutrients for the cell (B): While nutrients cross the cell membrane, membrane proteins do not provide nutrients; instead, they help transport them via specific channels or carriers.
- Cell division (E): Proteins in the cell membrane do not directly facilitate cell division. This process is primarily controlled by intracellular mechanisms involving the cytoskeleton and nuclear machinery.
In conclusion, membrane proteins are integral to cellular signaling, structural integrity, and transport, ensuring the proper function of cells and tissues.