Question

which of the following statements about logistic growth curves is true?
a. logistic growth curves are common for r-selected species.
b. logistic growth curves are j-shaped.
c. no organisms in nature experience logistic growth rates.
d. logistic growth curves increase exponentially at first, then experience slowed growth rates.

please select the best answer from the choices provided

a
b
c
d

Explanation:

🆕 New Concept Discovered: Population Growth Models
How populations grow when resources are limited

Step 1: Define Logistic Growth

Logistic growth describes how a population grows when resources are limited.

• The Shape: It produces an S-shaped curve rather than a J-shaped curve.
• The Process:

1. At first, when the population is small and resources are abundant, growth is rapid and looks exponential.
2. As the population grows and resources (like food, water, and space) become scarce, the growth rate slows down.
3. Eventually, the population size levels off at the environment's carrying capacity.

Step 2: Evaluate the Options

• a. Logistic growth curves are common for R-selected species.
• Incorrect. R-selected species (like bacteria or insects) reproduce rapidly and typically show exponential (J-shaped) growth, often followed by a crash. K-selected species (like humans or elephants) are more associated with logistic growth.
• b. Logistic growth curves are J-shaped.
• Incorrect. Exponential growth curves are J-shaped. Logistic growth curves are S-shaped.
• c. No organisms in nature experience logistic growth rates.
• Incorrect. Many natural populations (such as yeast, seals, and sheep) show logistic growth as they reach the limits of their environment.
• d. Logistic growth curves increase exponentially at first, then experience slowed growth rates.
• Correct. This perfectly describes the transition from the initial abundant-resource phase to the limited-resource phase of an S-curve.

Answer:

D