Question

QUESTION 3 For each of the following cellular processes identify cell membrane modifications that are involved, and provide a single phrase that describes how the cell membrane modification facilitates the identified activity. • Active transport • Tight junctions between cells • Mobility of sperm • Movement of mucous across the surface of cells

Answer 1

1. Active transport:- cell membrane modification- presence of membrane proteins( both integral and extrinsic proteins). These proteins helps in the transport of substances from a low concentration to high concentration across the cell membrane using the energy.
2. Tight junctions between cells- cell membrane modification- presence of tight junctional proteins, claudins. These proteins produces a diffusion barrier by controlling permeability of solutes between adjacent cells and also by restricting apical and basolateral diffusion of membrane components.
3. Mobility of sperm- cell membrane modification- presence of flagellum. Flagellum in the sperm helps in the sperm motility by helping in sperm capacitation and in the transfer of sperm to oocyte.
4. Movement of mucous across the surface of cells. cell modification- compound epithelium. Their main function is to provide protection against chemical and mechanical stresses by covering the dry surface of the skin by playing role in mucous secretion.