Slide 1 of 22 Copyright Pearson Prentice Hall Biology

Slide 2 of 22 Copyright Pearson Prentice Hall 5-1 How Populations Grow

Slide 3 of 22 Copyright Pearson Prentice Hall Characteristics of Populations What characteristics are used to describe a population?

5-1 How Populations Grow Slide 4 of 22 Copyright Pearson Prentice Hall Characteristics of Populations Three important characteristics of a population are its: geographic distribution density growth rate

5-1 How Populations Grow Slide 5 of 22 Copyright Pearson Prentice Hall Characteristics of Populations Geographic distribution, or range: the area inhabited by a population.

5-1 How Populations Grow Slide 6 of 22 Characteristics of Populations Population density: the number of individuals per unit area. Copyright Pearson Prentice Hall

5-1 How Populations Grow Slide 7 of 22 Characteristics of Populations Growth rate: the increase or decrease of the number of individuals in a population over time. Copyright Pearson Prentice Hall

5-1 How Populations Grow Slide 8 of 22 Copyright Pearson Prentice Hall Population Growth What factors affect population size?

5-1 How Populations Grow Slide 9 of 22 Copyright Pearson Prentice Hall Population Growth Three factors can affect population size: the number of births the number of deaths the number of individuals that enter or leave the population A population can grow when its birthrate is greater than its death rate.

5-1 How Populations Grow Slide 10 of 22 PopulationGrowth Immigration Vs. Emigration Root Word: Migrate (To move from one place to another) Copyright Pearson Prentice Hall

5-1 How Populations Grow Slide 11 of 22 Copyright Pearson Prentice Hall Population Growth Immigration: the movement of individuals into an area Does this increase or decrease the population? Why would animals move into a new area?

5-1 How Populations Grow Slide 12 of 22 Copyright Pearson Prentice Hall Population Growth Emigration: the movement of individuals out of an area. Does this increase or decrease the population? Why would animals move out of an area?

5-1 How Populations Grow Slide 13 of 22 Copyright Pearson Prentice Hall Exponential Growth What are exponential growth and logistic growth?

5-1 How Populations Grow Slide 14 of 22 Copyright Pearson Prentice Hall Exponential Growth Under ideal conditions with unlimited resources, a population will grow exponentially. the individuals in a population reproduce at a constant rate. The population becomes larger and larger

Slide 15 of 22 Copyright Pearson Prentice Hall Fictional "Tribbles" from Star Trek: One of the more peculiar species encountered, the defining characteristic of the Tribbles is their extreme reproductive rate. Over half of a Tribbles metabolism is devoted to reproduction, allowing them to bear a litter of young every twelve hours. With an average litter of ten, a single Tribble can therefore create a population of 1,771,561 within three days, and an amazing 304,481,639,541,400,000,000,000,000,000,000,000,000,000,000, 000,000,000,000,000,000 in thirty days!

5-1 How Populations Grow Slide 16 of 22 Copyright Pearson Prentice Hall Logistic Growth In nature, exponential growth does not continue in a population for very long. What factors can cause exponential growth to stop?

5-1 How Populations Grow Slide 17 of 22 Copyright Pearson Prentice Hall Logistic Growth As resources become less available, the growth of a population slows or stops. a population's growth slows or stops following a period of exponential growth.

5-1 How Populations Grow Slide 18 of 22 Copyright Pearson Prentice Hall Logistic Growth Carrying Capacity The largest number of individuals of a population that an environment can support. What is your Carrying Capacity?

5-1 How Populations Grow Slide 19 of 22 Copyright Pearson Prentice Hall Logistic Growth Describe what happens when a population reaches its carrying capacity. Logistic growth is characterized by an S-shaped curve.

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Slide 21 of 22 Copyright Pearson Prentice Hall 5-1 Population density is the number of individuals a.that are born each year. b.per unit area. c.that immigrate. d.that emigrate.

Slide 22 of 22 Copyright Pearson Prentice Hall 5-1 When the birthrate of a population exceeds its death rate, the population a.decreases. b.increases. c.stays the same. d.increases then decreases.

Slide 23 of 22 Copyright Pearson Prentice Hall 5-1 An S-shaped curve on a graph of population growth is characteristic of a.exponential growth. b.logistic growth. c.carrying capacity. d.delayed growth.

Slide 24 of 22 Copyright Pearson Prentice Hall 5-1 Exponential growth in a population slows down or stops as a.resources become limited. b.rate of immigration increases. c.rate of emigration decreases. d.birth rate increases.

Slide 25 of 22 Copyright Pearson Prentice Hall 5-1 Exponential growth rate means that each new generation of a population a.adds the same number of new individuals as the previous generation did. b.increases at the same rate as the previous generation. c.is the same size as the generation before. d.increases by a varying amount.

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