Question

Name the process which is useful for the movement of substances like ${\text{C}}{{\text{O}}_{\text{2}}}$ and ${{\text{O}}_{\text{2}}}$
A. Diffusion
B. Osmosis
C. Active diffusion
D. Reverse osmosis

Answer 1

Hint: The incremental flow/dispersion of concentration inside a body, without a net movement of matter due to such a concentration gradient. Molecules will also travel around in space after a substance has fully moved via a space, eliminating the concentration gradient, but there would be no net movement of the amount of molecules from one field to another, a condition referred to as dynamic equilibrium.

Complete answer:
First we should know about the movement of substances to answer this question. The displacement of substances (including the plasma membrane) can occur through a semipermeable membrane. A semipermeable membrane requires certain chemicals, but not others, to move through.
Now, let us find the solution from the options-
${\text{C}}{{\text{O}}_{\text{2}}}$ and ${{\text{O}}_{\text{2}}}$ are chemicals, so they travel by diffusion in or out of the cell. Diffusion is a mechanism in which, due to its kinetic energy, the gaseous molecules disperse and the flow of molecules is from high to low concentration.
The osmosis of the random net migration of solvent molecules into an area of higher solvent concentration via a selectively permeable membrane in the direction that appears to equalise the levels of solvent on both sides. Thus, option B is not the correct option.
Active transport is the passage of molecules toward the concentration gradient through a cell membrane from a lower concentration zone to a higher concentration zone. To accomplish this movement, active transportation involves cellular energy. Thus, option C is not the correct option.
Reverse osmosis is a method of water purification that utilizes a partly permeable membrane to extract undesired molecules, larger particles and ions from drinking water. Thus, option D is not the correct option.
So, the correct answer is “Option A”.

Note:
A gradient is the difference in the value of a variable with a change in another variable, typically distance, for instance, concentration, stress, or temperature. A variation of concentration across a distance is called a gradient of concentration, a change of pressure across a distance is named a gradient of pressure, and a change of temperature across a distance is known a gradient of temperature.