Click to play Essential Questions What are the factors that effect population growth? What are some of the effects that overpopulation have on an environment? Essential Questions What are the factors that effect population growth? What are some of the effects that overpopulation have on an environment?

smallest unit of living things group of similar cells organized to work together group of different kinds of tissues working together group of organs working together one individual living thing all organisms of the same kind living in one area all interacting populations in an ecosystem all living and nonliving things interacting within a certain area large region with typical plants and animals that includes several ecosystems cell Population Dynamics

How populations change in size due to birth rate/immigration and death rate/emigration and limiting factors ( abiotic and biotic) Birth Rate: (number of live birth per 1000) How does death rate affects population size? Death Rate ( number of death per 1000) How does death rate affects population size? Immigration: ( movement into an area) How does immigration affects population size? Emigration: (movement out of an area) How does emigration affects population size?

Population Size What goes up must come down Increases in population: through birth or immigration Decreases in population: through death or emigration. What goes up must come down Increases in population: through birth or immigration Decreases in population: through death or emigration. Change in Population Change in Population =

“Boom and Bust” “Boom then stable” Can you think of something in nature that exhibits exponential growth? Logistic growth? Population will follow two general paths: When faced with unlimited resources it will grow exponentially When faced with limited resources it grow logistically Population will follow two general paths: When faced with unlimited resources it will grow exponentially When faced with limited resources it grow logistically

Population size (N) Time (t) Carrying capacity (K) Environmental resistance Biotic potential Exponential growth Populations grow rapidly with ample resources (biotic potential), but as resources become limited (environmental resistance), its growth rate slows and levels off Carrying Capacity (K) is the maximum number of organism that an area can support Populations grow rapidly with ample resources (biotic potential), but as resources become limited (environmental resistance), its growth rate slows and levels off Carrying Capacity (K) is the maximum number of organism that an area can support Can you think of some resources that could limit population growth? Characterize these resources as abiotic or biotic?

Exponential and Logistic Population Growth: J-Curves and S-Curves As a population levels off, it often fluctuates slightly above and below the carrying capacity.

By the year 2020, 9 to 10 billion humans are expected to inhabit the planet. Do you think the world is overpopulated? Click to play