Ecology Quiz study guide
1.Write the meaning/definition for each term: ecology, habitat, abiotic, biotic, population, community, ecosystem, biome, biosphere, carrying capacity, limiting factor, immigration, emigration, birth rate, death rate, niche, adaptation
Ecology the study of how living things interact with each other and their environment.
Habitat - an environment that provides the things an organism needs to live grow and reproduce
Abiotic - nonliving parts of an ecosystem
Biotic - living parts of an ecosystem
Population - all members of one species that interact in an area

Community - all different populations that live together in an area
Ecosystem - community of organisms that live in an area and their non-living surroundings
Biome - a group of ecosystems with similar climates and organisms
Biosphere - all biomes/area of life on Earth
Carrying capacity - the maximum amount of organisms an ecosystem can hold
Limiting factor - a resource that limits the size of a population
Immigration - organisms moving into a population (increases population size)
Emigration - organisms leaving a population
(decreases population size)

Birth rate - the number of individuals born in an amount of time
Death rate - the number of individuals dying in an amount of time.
Niche - the role or job of an organism in the ecosystem. (a crab lives on the bottom and eats dead things- that is its niche)
Adaptation - a special characteristic that increases chances for survival
2.How do scientists organize the different levels of an ecosystem? What is the order from smallest scale to largest?
Organism, population, community, ecosystem, biome, biosphere

forest
3.Give an example of a biotic factor and the abiotic parts that create an environment for its survival.
A tree (biotic) needs sun, water and air to grow
4.If you count 20 bears in a 200 meter 2 random sample. Then you calculate that the forest is 20 times that size (4000m 2 ). What is your population estimate? Use
20 bears (20 times) = 400 bears in the whole

5.What is the difference between direct and indirect sampling?
Direct is counting all by seeing the organism
Indirect involves counting signs of organisms and estimating population size
6.Which sampling method will you use when working with a large population, in a concentrated area, whose members can not be observed directly or indirectly?
Tag and recapture

7.Explain the technique of simple random sampling. When is it useful?
A random sample is chosen from a larger area.
From the samples, an estimate is made to apply to the whole population. It is useful when there is a large population that is spread over a large area
8.Explain the technique of mark and recapture. When is it useful?
Organisms from a population are captured and tagged- and then released to mix with the population.

The ecologist returns and captures again. The number of recaptured is compared to the total number captured and an equation is used to calculate an estimate.
Use this when working with a large population, in a concentrated area, whose members can not be observed directly or indirectly
9.What is the meaning of population density?
The number of organisms in a given area
10.
What is the formula for population density?
Number of organisms/unit area

11.
Calculate the population density for the following example. Show your work in the 4 steps used in your notes. Include units with all numbers for full credit.
1.
Number of organisms/unit area
2.
Number = 16 lions
3.
Area = 70 km 2
4.
16 lions / 70 km 2 = 0.23 lions/km 2
L L
L L LLL L L
LLL LL L L
7 km
10 km
12.
Give 3 examples of limiting factors.
Water, food, space
13.
Describe what happens to a population when there is a high birth rate?

The population grows
14.
Write the situation described in #3 as a population statement formula
Birth rate > death rate= growing population
15.
Describe what happens to a population when there is a high death rate?
The population declines
16.
Write the situation described in #5 as a population statement formula
Death rate> birth rate= declining population

17.
Make a graph showing population change for a typical population of rabbits over 10 year period. Imagine that the population starts at 25 in year 1 and reaches the highest amount of 200 in years 6 and 9. Identify/label areas of

population increase , decrease , and carrying capacity on the graph.
Increasing population
Carrying capacity
Decreasing population
18.
What are 3 main types of interactions between living things in an ecosystem?

Competition, symbiosis, predation
19.
Give 2 specific examples of how organisms have adapted to reduce competition.
Fish in a pond can have different diets
Birds can have special beaks that allow them to eat different parts of the same fruit
20.
What does the term “limited resource” mean? Give 2 examples.
A resource in the ecosystem that reduces population size
Examples: water, space

21.
What is the difference between habitat and a niche?
A habitat is an environment that provides the things needed for an organism to live, grow and reproduce a niche is the role in the environment
22.
Can two different species occupy the same habitat? Explain.
Yes they can as long as they do not occupy the same niche.
23.
Can 2 organisms occupy the same niche?

No. They will compete with each other until one dies out