AP Biology Questions on Population Growth and Regulation

📚 Quick Study Guide

• 📈 Population Growth: Describes how the number of individuals in a population increases or decreases over time.
• ➕ Birth Rate (b): Number of births per individual per unit time.
• ➖ Death Rate (d): Number of deaths per individual per unit time.
• ➗ Per capita rate of increase (r): $r = b - d$
• 🌱 Exponential Growth: Population increase under idealized conditions (unlimited resources). Equation: $\frac{dN}{dt} = r_{max}N$, where $N$ is population size, $t$ is time, and $r_{max}$ is the intrinsic rate of increase.
• 🚧 Logistic Growth: Population growth that levels off as population size approaches carrying capacity. Equation: $\frac{dN}{dt} = r_{max}N(\frac{K-N}{K})$, where $K$ is the carrying capacity.
• ⛰️ Carrying Capacity (K): The maximum population size that a particular environment can sustain.
• 🌍 Density-Dependent Factors: Factors that affect population growth based on population density (e.g., competition, predation, disease).
• 🌡️ Density-Independent Factors: Factors that affect population growth regardless of population density (e.g., natural disasters, weather).

🧪 Practice Quiz

1. What is the per capita rate of increase (r) if the birth rate (b) is 0.12 and the death rate (d) is 0.07?
   1. 0.19
   2. 0.05
   3. 0.84
   4. 1.71
2. In the logistic growth model, what does 'K' represent?
   1. The population size at time zero
   2. The carrying capacity
   3. The per capita rate of increase
   4. The death rate
3. Which of the following is an example of a density-dependent factor that can limit population growth?
   1. A volcanic eruption
   2. A severe drought
   3. Increased competition for resources
   4. A flash flood
4. What happens to population growth as it approaches carrying capacity in the logistic growth model?
   1. It increases exponentially
   2. It decreases to zero
   3. It levels off
   4. It fluctuates randomly
5. If a population is growing exponentially, what happens to its growth rate?
   1. It remains constant
   2. It decreases over time
   3. It increases over time
   4. It fluctuates randomly
6. Which equation best describes exponential population growth?
   1. $\frac{dN}{dt} = r_{max}N(\frac{K-N}{K})$
   2. $\frac{dN}{dt} = r_{max}N$
   3. $\frac{dN}{dt} = K - N$
   4. $\frac{dN}{dt} = r_{max}$
7. Which of the following is an example of a density-independent factor?
   1. Competition
   2. Predation
   3. Disease
   4. Natural Disaster