1. Parts of an Ecosystem
1. Habitat- The place where an organism lives and that provides the things it needs.
2. Biotic factors- The living parts of an ecosystem.
Some examples of biotic factors are:
- Grass - Animals
- Trees - Bacteria
3. Abiotic factors- The nonliving parts of an ecosystem.
Some examples of abiotic factors are:
- Water - Oxygen
- Sunlight - Rocks

2. Many prairie dogs in the same area represent a population
4. Organism- the smallest unit of organization, represents one of a particular species
A prairie dog is an organism
of a particular species
5. Species- A group of organisms that are similar and reproduce to produce fertile offspring.
6. Population- All the members of one species in a particular area
Many prairie dogs in the
same area represent a population

3. abiotic factors form the ecosystem
7. Community- All the different populations that live together in an area.
All the populations in an area that interact with one another
The community and
abiotic factors form the ecosystem
8. Ecosystem- All the living and nonliving things that interact in an area.
9. Ecology- The study of how living things interact with each other and their environment.

4. Section 1-2 vocabulary
Population density – The number of individuals in a specific area. Some methods of determining density are direct and indirect observation, sampling, and mark and recapture.
Direct observation – This method counts, one-by-one, all of its members.
Indirect observation – This method counts the signs of the members of a population like tracks, nests…
Sampling – This method estimates the number of members in a population. One way of doing this is to count the number of organisms in a small area and then multiplying to find the number in a larger area.
Mark-and-recapture – This method captures, marks, and releases the members. Later another group of animals is captured. The number of marked animals in the second group helps in estimating the population size.
Estimate – an approximation of a number based on reasonable assumptions
Birth rate – the number of births in a population in a certain amount of time
Death rate – the number of deaths in a population in certain amount of time
Immigration – moving into a population
Emigration – leaving a population

5. Carrying capacity – the largest population that an area can support
Limiting factor – an environmental factor that prevents a population from increasing
Carrying capacity – the largest population that an area can support
Cheat Mountain Salamander
Red Spruce disappearing

6. Section 1-3 vocabulary
22. Natural Selection- Process by which individuals that are better adapted to the environment are more likely to survive and reproduce than others.
23. Adaptations- The behaviors and physical characteristics of species that allow them to live successfully in their environments.
24. Niche- An organism’s particular role in an ecosystem, or how it makes its living.
25. Competition- The struggle between organisms for the limited resources in a habitat.
26. Predation- An interaction in which one organism kills and eats another.
27. Predator- The organism that does the killing in predation.
28. Prey- An organism that is killed in predation.

7. 29. Symbiosis- A close relationship between species that benefits at least one of the species. There are 3 types of symbiotic relationships: mutualism, commensalism, and parasitism.
30. Mutualism- A relationship between two species in which both species benefit.
31. Commensalism- A relationship between two species in which one species benefits and the other is neither helped nor harmed.
32. Parasitism- A relationship in which one organism lives on or inside another and harms it.
33. Host- The organism that a parasite lives in or on in parasitism.