Individuals Populations and Environment

Populations are Made Up of Individuals A group of individuals of the same type that lives in a particular area is called a population. A group of individuals of the same type that lives in a particular area is called a population. To define a population, you need to identify the type of individuals, the time, and the place. To define a population, you need to identify the type of individuals, the time, and the place. Looking at only a few individuals may be misleading. Looking at only a few individuals may be misleading.

Four Rates Determine Population Size Characteristics that determine a population size are: Characteristics that determine a population size are: 1. How many organisms die 2. How many organisms are added by reproduction 3. How many individuals come in form another area 4. How many individuals leave and move to another area

A decrease in individuals represents the death rate, or mortality rate. A decrease in individuals represents the death rate, or mortality rate. Rate at which reproduction increases the population is called the birthrate. Rate at which reproduction increases the population is called the birthrate. Immigration occurs when one or more individuals move to an area where others of their type can be found. Immigration occurs when one or more individuals move to an area where others of their type can be found. Emigration occurs when individuals leave an area. Emigration occurs when individuals leave an area.

The Environment Limits Population Size The environment is everything that surrounds and affects and organism. The environment is everything that surrounds and affects and organism. The environment is made up of 2 parts: living and nonliving. The environment is made up of 2 parts: living and nonliving. The living (or recently living) part is called the biotic environment. The living (or recently living) part is called the biotic environment. The nonliving part is called the abiotic. The nonliving part is called the abiotic.

Any abiotic or biotic factor that can affect the growth of a population is called a limiting factor. Any abiotic or biotic factor that can affect the growth of a population is called a limiting factor. Temperature, climate, water, and weather are all limiting factors. Temperature, climate, water, and weather are all limiting factors.