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| Name 4 important characteristics of a population. | Its geographic distribution, density, growth rate, and age structure. |
| What is meant by geographic distribution? | It's the area inhabited by a population. |
| What is a "population"? (review) | It's a group of individuals of the same species that live in the same area. |
| What is meant by population density? | It refers to the number of individuals per unit of an area. (see ex. pg. 119) |
| What happened to the growth rate of some sea otters recently? | They started to decrease because killer whales are eating them. |
| What are 3 factors that affect a population's size? | The number of births, the number of deaths, and the number of individuals entering or leaving the population |
| In general, how does a population growth remain stable? | The birthrate equals the death rate + immigration and emigration are also equal. |
| Define immigration as it relates to a population. | It's movement of individuals into an area ("I" and "in"). |
| Define emigration. | It's the movement of individuals out of an area ("E" and "exit") |
| What are some factors that may contribute to emigration? | Young animals mature, leave the area, mate, establish new territory; shortage of food. (These also increase population in other areas where these animals go.) |
| Name some factors that help a population multiply, increasing the population size. | Abundant space, plentiful food, protection from predators & disease. |
| What is exponential growth? | It's a growth pattern in which the individuals in a population reproduce at a constant rate. (see pg. 121 for the bacteria example!) |
| When does a population grow exponentially? | When ideal conditions exist with unlimited resources, exponential growth occurs. |
| Why is the growth rate of elephants slow? | An infant is produced only every 2-4 years; offspring take about 10 years to mature. |
| What is logistic growth? | It's a growth pattern in which a population's growth rate slows or stops following a period of exponential growth. |
| What slows of stops the growth of a population? | Resources become less available, the birth rate decreases, birth rate increases, rate of immigration decreases, death rate increases. |
| What is meant by the carrying capacity of the environments for a particular species? | It's the largest number of individuals of a population that a given environment can support. |
| Why does exponential growth increase over time? | There are more individuals that reproduce; this results in a larger number of offspring each generation that follows. |
