Chapter 25, Problem 1A

Summary Introduction

Introduction:

Carrying capacity is the maximum limit of population that any biological system can handle for an indefinite time period if the food and other necessary resources are in adequate amount. It tells about the limits of a biodiversity or any ecosystem.

Answer to Problem 1A

Correct answer:

Population size decreases above carrying capacity due to a range of factors depending on the species concerned, but can include insufficient space, food supply, or sunlight. Therefore, option (c) is correct.

Explanation of Solution

Reason for the correct statement:

The carrying capacity of an environment depends on many factors and it may vary from specie to specie. The factors on which the carrying capacity depends are food availability, water supply living space and so on.

Option (c) is given as “decrease to the level of the carrying capacity”.

“When the carrying capacity of the environment is exceeded, the population will typically decrease to the level of the carrying capacity”, it is the right answer.

Hence, option (c) is correct.

Reasons for the incorrect statements:

Option (a) is given as “increase, but at a slower rate”.
Since population size decreases above carrying capacity due to a range of factors depending on the species concerned, but can include insufficient space, food supply, or sunlight. So, it is a wrong answer.

Option (b) is given as “stabilize at the highest level reached”.
As when the carrying capacity of the environment is exceeded, the population would not be stabilized after reaching the highest level instead of it the population decrease to the level of carrying capacity. So, it is a wrong answer.

Option (d) is given as “go extinct”.
As when the carrying capacity of the environment is exceeded, the population would not be extinct but decrease to the level of carrying capacity. So, it is a wrong answer.

Hence, options (a), (b), and (d) are incorrect.

Conclusion

Anthropogenic activities affect the carrying capacity of an ecosystem. The factors that are related to humans that affects the carrying capacity are overpopulation, intensity of the resource use and the pollution.

An increase in the carrying capacity of environment the population will typically decrease to the level of the carrying capacity so as to stabilize the change and in order to maintain homeostasis.