Which term best describes population growth that increases as population size increases, producing an exponential pattern?

• A. Plateau
• B. Carrying capacity
• C. Exponential growth
• D. Decline

Answer: (C)

Growth that accelerates as population size increases is exponential growth. When the per capita growth rate remains positive and roughly constant, each generation adds a number of individuals proportional to how many are already there, so a larger population yields more births and the total grows faster over time. This creates a J-shaped curve, often seen when a population encounters abundant resources and little competition or predation—think bacteria multiplying in a clean, nutrient-rich environment or a species newly introduced to a suitable habitat. Mathematically, it follows N(t) = N0 e^(rt) with r > 0, meaning growth is proportional to N and speeds up as N grows.

This contrasts with a plateau, where growth slows and levels off as limits bite; carrying capacity refers to the maximum population sustainable by the environment, leading to logistic growth rather than true exponential growth. Decline is simply a decrease in population size.