Question

In terms of permeability, the cell wall and plasmalemma are
A. Permeable and differentially permeable respectively.
B. Both semipermeable.
C. Semi permeable and permeable.
D. Both differentially permeable.

Answer 1

Cell wall is present after the plasma membrane, the cell wall is permeable in nature whereas plasma membrane is semipermeable in nature that means cell membrane of plasma membrane allow the specific kind of substance to move in or out of the cells to main the cell homeostasis.

Complete answer:
Cell wall is found in plant tissue and absent in animals while plasma membrane is present in both plant and animal cells. Cells provide rigidity to the plant cell and maintain the integrity of the cell while the plasma membrane protects the protoplasm of the cell and show the selective permeability regarding solute and solvent. The plasma membrane has some receptors, which help in the cell to cell communication.

Cell wall is not only present in the plant but also found in fungi and bacteria, it is composed of cellulose, hemicellulose lignin and pectin. The main function of the cell wall is to regulate and control cell growth and direction. It allows the movement of small molecules freely, the size exclusion is to be 30-60kDa and protect the cell from damage and pathogen invasion.

Plasma membrane or cell membrane is the outermost covering of the animal cell, which is a semipermeable membrane in nature, which is composed of lipid and protein and its functions are as follow:-

Protects the cell integrity, provides support and shape of the cell, helps in cell growth via balancing of endocytosis and exocytosis, this membrane helps in signalling and communication.

Hence, the correct answer is option (A).

Note: Due to the nature of permeability and semi-permeability cell show a different type of behaviour when they place into three different type of solution such as, in a hypertonic solution, cell shrinks, In hypotonic solution cell swells up and increase in size and in isotonic solution cell remain same there no change takes place.