Question

Assertion (A): The rate of breathing in aquatic organisms is much faster than in terrestrial organisms.
Reason (R): The amount of oxygen dissolved in water is much lower than the amount of oxygen in air.
Which of the following is correct?

A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, but R is not the correct explanation of A.
C. A is true, but R is false.
D. A is false, but R is true.

[1 Mark]

Answer 1

Solution:

A. Both A and R are true, and R is the correct explanation of A.

The amount of oxygen available to the aquatic organisms in the form of dissolved oxygen is fairly low as compared to the amount of oxygen available to the terrestrial organisms in the form of atmospheric oxygen. Hence, aquatic organisms need to breath at a faster rate to fulfill their oxygen requirements.

[1 Mark]