Ecology 37

Question 1

Population

Answer 1

Group of individuals of the same species, ability to interact and interbreed with each other.

Question 2

Habitat

Answer 2

Are of temperature, humidity, soil, competitors, predators, etc…

Question 3

Niche

Answer 3

Functional role in the ecosystem. Total of an organism’s interaction with biotic and abiotic resources of its environment

Question 4

Ecosystem

Answer 4

All organisms present in a particular are and their physical environment. Biotic and abiotic components.

Question 5

Community

Answer 5

Group of populations comprised of different species.

Question 6

Dominant species

Answer 6

a) Possess greater biomass

b) Found in greater numbers

Question 7

Climax community

Answer 7

Stable community in which populations of animals/plants remain in equilibrium. Succession leads to climax community.
Succession is progressive series of changes.

Question 8

Primary Succession

Answer 8

New volcanic island, lava flows, glacier retreats, sand dunes. When the terrain was without life.
Lichens and moss usually are first to colonize.

Question 9

Secondary succession

Answer 9

Series of community changes. An existing community has been cleared out by a disturbance such as a fire. Fast that primary because soil already exists.

Question 10

Ozone layer

Answer 10

In the stratosphere. Protects us from harmful and damaging effects of UV radiation.

Question 11

Early earth was a _____ atmosphere

Answer 11

Reducing atmosphere. It containe CH4, NH3, CO2, H2S, and water vapor but no O2.
Cyanobacteria helped through photosynthesis.

Question 12

Greenhouse gas

Answer 12

CH4, N2O, hydrofluorocarbons, chlorofluorocarbons, CO2, H2O vapor.
Gas in atmosphere that traps heat.

Question 13

Continental drift

Answer 13

Supercontient Pangaea and was 250 million years ago. Helped explain how fossils in West Africa were the same as those found in South America. The Appalachian mountains in the U.S. fit with the Caledonian Mountains of Scotland.
Tectonic plates.

Question 14

The mantle of the Earth

Answer 14

Encloses the hot core rich in Fe and Ni. The earth’s crust consists of 47% O2 and 28% silicon.
The air we breath is mostly N2, the earth’s crust is mostly O2.

Question 15

Lakes and ponds are often classified by their nutrient status.

Answer 15

Oligotrophic: nutrient poor but O2 rich; low productivity of phytoplankton; deep lakes - water is blue or green.
Eutrophic: nutrient rich, lower O2 contentl shallow area; high productivity of phytoplankton; water is green/yellow or brown/green.

Question 16

Biomes

Answer 16

Large areas of Earth which are characterized by climax community it supports.
Marsh: Wet grassland
Swamp: Wooded wetland

Question 17

Populations display certain characteristics

Answer 17

a) Size: # of individuals
b) Density: # of individuals per unit area of volume
c) Distribution: pattern of dispersal through its habitat
d) Age structure: pre-reproductive, reproductive, or post reproductive classifications.

Question 18

Uniform dispersion

Answer 18

Suggests competition among members. Animals that defend their area tend to be uniformly spaced to divide the area between them.

Question 19

Factors affecting sustainable population

Answer 19

Predation, competition, available resources, pollution, disease

Question 20

Carrying capacity

Answer 20

of individuals that can be sustained indefinitely by the resources in a given area. Births balanced by deaths.

Question 21

Population growth rate depends on

Answer 21

Birth rate, death rate, rates of immigration and emigration

Question 22

Population growth regulation

Answer 22

Density dependent mechanism: decrease birth rate or increase death rate.
When a population grows its density increases and so does competition for resources, predation, wastes, parasitism, and disease.

Question 23

Density independent factors

Answer 23

Fires, earthquakes, snowstorms, floods

Question 24

Human populations grow exponentially when

Answer 24

When birth rate remains slightly above the death rate and both rates are constant.

Question 25

Life history strategies of organisms

r-strategist

Answer 25

High growth rate with many offspring. Little parental supervision, short life spans and waste much energy.
Exponential growth model

Question 26

Life history strategies of organisms

k-strategist

Answer 26

Low growth rate with few offspring. More stable environment and efficient energy
Logistic growth model

Question 27

Cohort

Answer 27

Group of same age individuals in a population

Question 28

Fundamental niche

Answer 28

Theoretical niche in which no limiting factors are present. No competitors, no disease, no parasites, and no predators.

Question 29

Realized niche

Answer 29

Niche with all interactions.

Question 30

Symbiosis

Answer 30

Ecological relationship between organisms of different species living in a community.

Question 31

Commensalism

Answer 31

One organism benefits, the other is neither harmed/helped

Question 32

Parasitism

Answer 32

One benefits, one harmed

Question 33

Interspecific competition

Answer 33

Different individuals or a species compete for a resource that limits their growth and survival.

Question 34

Interference competition

Answer 34

Animals interfere with the same species in competition

Question 35

Exploitation competition

Answer 35

Both species have equal access to a resource but one exploits it at a faster rate. Indirect harm to the other organisms growth and survival.

Question 36

Competitive exclusion

Answer 36

A slight advantage will cause one to be eliminated.

If niches are identical, two species will be unable to coexists permanently.

Question 37

Resource partitioning

Answer 37

E.G. Field with three plants, each plant exploits a different part of the soil.