P OPULATION F LUCTUATION N OTES

R EVIEW Q UESTION 1: What factors lead to exponential growth in populations?

R EVIEW Q UESTION 2: What factors lead to logistic growth curves?

C HECK F OR U NDERSTANDING When the birthrate of a population exceeds its death rate, the population decreases. increases. stays the same. increases then decreases.

C HECK FOR U NDERSTANDING An S-shaped curve on a graph of population growth is characteristic of exponential growth. logistic growth. carrying capacity. delayed growth.

C HECK FOR UNDERSTANDING Exponential growth in a population slows down or stops as resources become limited. rate of immigration increases. rate of emigration decreases. birth rate increases.

P OPULATION F LUCTUATION N OTES 1. Limits to Population Growth: A. A limiting factor is a factor that causes population growth to decrease.

P OPULATION F LUCTUATION N OTES 1. Limits to Population Growth: A limiting factor is a factor that causes population growth to decrease. a. Density Dependent Factors are limiting factors that depend upon the population size. Examples include: Competition Predation Parasitism Disease

P OPULATION F LUCTUATION N OTES b. Density Independent Factors are limiting factors that do not depend upon a population’s size. Examples include: Natural Disasters Seasonal Variation Human activities such as deforestation

C HECK FOR U NDERSTANDING A limiting factor that affects all populations in similar ways regardless of their size might be drought. disease. predation. crowding.

C HECK FOR U NDERSTANDING Within a limited area, if the population of a predator increases, the population of its prey is likely to increase. decrease. remain about the same. become extinct.

C HECK FOR U NDERSTANDING Which of the following is a density-independent factor affecting populations? predation disease a destructive hurricane parasites