Chapter 5

NCERT
Class 9
Science
Solutions
1&2. How do substances like CO2 and water move in and out of the cell? Discuss Why is the plasma membrane called a selectively permeable membrane?

Question:

How do substances like CO2 and water move in and out of the cell? Discuss Why is the plasma membrane called a selectively permeable membrane?

Answer:

The concentration of CO2 in the outer environment of the cell is less than the concentration of CO2 present in the cells. As there is a difference in the concentration of CO2 inside and outside the cell, at the same time CO2 is expelled from the cell by diffusion from high concentration to low concentration. Similarly when the oxygen concentration in the cell decreases, O2 moves from outside to the inside of cell by diffusion.

Buy Latest Books

Teacher's Corner