AP BIOLOGY

Detailed explanation-1: -In logistic growth, a population’s per capita growth rate gets smaller and smaller as population size approaches a maximum imposed by limited resources in the environment, known as the carrying capacity ( K).

Detailed explanation-2: -According to the logistic growth model, a population first grows exponentially because there are few individuals and plentiful resources. As the population gets larger and approaches the environment’s carrying capacity, resources become more scarce and the growth rate slows.

Detailed explanation-3: -Answer and Explanation: The correct answer is (B) If a population is at the carrying capacity of the environment, then the birth rate will more or less equal the death rate (i.e., zero population growth).

Detailed explanation-4: -When resources are limited, populations exhibit logistic growth. In logistic growth, population expansion decreases as resources become scarce, leveling off when the carrying capacity of the environment is reached, resulting in an S-shaped curve.

Detailed explanation-5: -Definition: Carrying Capacity The carrying capacity of an organism in a given environment is defined to be the maximum population of that organism that the environment can sustain indefinitely. We use the variable K to denote the carrying capacity. The growth rate is represented by the variable r.