1. POPULATIONS

2. The study of the interactions that take place among organisms and their environment

3. Biosphere The part of Earth that supports life
Top portion of Earth's crust
All the waters that cover Earth's surface
Atmosphere that surrounds Earth.

5. Ecosystem
All the organisms living in an area and the nonliving features of their environment

7. Population
All the organisms in an ecosystem that belong to the same species

9. Community
All the populations in an ecosystem

11. KEY FEATURES OF POPULATIONS
1. Population size
is the number of individuals in a population.
has an important effect on the ability of the population to survive.
A small population is more likely to become extinct:
in the case of a natural disaster
due to inbreeding where the population is more genetically alike. Recessive traits, including diseases, are more likely to appear.
Variation is reduced, so it is harder to adapt to changes.

12. The place in which an organism lives
Habitat
The place in which an organism lives
provides the kinds of food and shelter, the temperature, and the amount of moisture the organism needs to survive

14. KEY FEATURES OF POPULATIONS, con’t
2. Population density
– the number of individuals in a given area.
– if they are too far apart they may only rarely encounter one another resulting in little reproduction.

15. Competition Demand for resources that supply a community Food Water
Space

16. Competition
Competition caused by population growth affects many organisms, including humans
Limits population size

17. Limiting Factor
Anything that restricts the number of individuals in a population.
Includes living and nonliving features of the ecosystem
Examples: food, sunlight, temperature

18. Population size is limited by:
Depend on how many are in an area:
Disease
Competition
Predators
Parasites
Food
Crowding
The greater the population, the greater effect these factors have.
Ex. Black plague in the Middle Ages – more deaths in cities
Does NOT depend on how many are in an area:
Volcanic eruptions
Temperature
Storms
Floods
Drought
Chemical pesticides
Major habitat disruption (as in the New Orleans flooding)
Most are abiotic factors

20. Biotic Potential
The potential growth of a population if it could grow in perfect conditions with no limiting factors.

21. Carrying Capacity
Biotic potential is nice to think about…but doesn’t happen because of limiting factors.
The carrying capacity is the largest number of individuals of one species that an environment can support

25. Kaibab Deer Population