Final answer:
Exponential population growth is characterized by a rapid increase in growth rate as the population size increases, depicted by a J-shaped curve. This occurs under ideal conditions with unlimited resources.
Step-by-step explanation:
A characteristic of exponential population growth is that the initial population growth is rapid. In this form of growth, as the population size increases, so does the growth rate. When resources are unlimited, populations tend to grow exponentially, indicated by a J-shaped curve. Populations can grow more rapidly as they become larger. However, exponential growth cannot be sustained indefinitely because resources will eventually become limited, leading to a shift to logistic growth where the population levels off.