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Population
Three important characteristics of a population are its geographic distributions, density and growth rate
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Population denstity
number of indiciduals per unit area
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Population Growth
Three factors can affect population size: the number of births, death rate and number of individuals who leave and enter the population.
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Exponential growth
- occurs when the indiiiduals in a population reproduce at a constant rate
- in the prescence of unlimited resourced, a population will grow exponentially.
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Carrying capacity
- The largest number of individuals that a environment can support.
- As resources become less available, the growth of a population slows or stops.
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Limiting factor
is a gactor that causes a population growth to decrease,
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density dependent factor
- depends on population size
- competition: with one another for food and necesities
- Predation: as a predator's population decreases, the prey's increases.as the predator's population increasem the prey's decreases
- Parastism and disease: kill and decrease a population
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Density-independent factors
- regardless of population size
- Human Disturbances: have cause disasters (greenhouse)
- Climate Extremes: extremes of cold or hot can toll on a population. They can also affect the population of the consumers within the food web and affect other consumers
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