1. Background Information

2. What is a Limiting Factor? Limiting Factors are… (two similar definitions) conditions of the environment that limit the growth of a species. biotic and abiotic factors that prevent the continuous growth of a population.

3. What is a Limiting Factor? Populations would continue to increase if they had all of the resources they require in unlimited amounts, but there are always factors that limit their increase. Limiting factors control population growth.

4. What is Carrying Capacity? Carrying capacity is the number of individuals of a species that an ecosystem can support.

5. What is Carrying Capacity? Because of these limiting factors, each ecosystem has a finite capacity for growth connected to its carrying capacity.

6. Population Growth Curves Exponential Growth - J Logistic Growth - S

7. Exponential Growth Occurs when there is unlimited resources Causes a population to increase in size rapidly J-shaped curve No limiting factors! Biotic potential = the estimated population size under optimal environmental conditions

8. Logistic Growth Occurs when there are limited resources Causes a population to grow and then stabilize at carrying capacity (k) S-shaped curve Limiting factors control population size (aka environmental resistance)

9. Carrying Capacity & Limiting Factor Review In nature, populations of organisms rarely grow uncontrolled. Each ecosystem has a carrying capacity (or number or organisms it can sustain/support). Remember, limiting factors are biotic and abiotic factors that prevent the continuous growth of a population. Because of limiting factors, the number of organisms in a population is often well below carrying capacity.