Module 4: Ecosystem Dynamics

Question 1

biotic

Answer 1

living components of an ecosystem

Question 2

abiotic

Answer 2

non-living components of an ecosystem
e.g. light availability, temperature, pH levels, water availability, soil, oxygen, altitude

Question 3

accuracy

Answer 3

How well the result was measured?
- human error
- equipment error
- digital vs. analog

Question 4

reliability

Answer 4

Repeated multiple times, with consistent results

Question 5

validity

Answer 5

How fairly were the results achieved?

Question 6

niche

Answer 6

• the sum total of a specie’s use of the biotic and abiotic resources in its environment. It is the functional role and position of an organism in the ecosystem

Question 7

ecological niche

Answer 7

an ecological niche is the role and position a species has in its environment; how it meets its needs for food and shelter, how it survives, and how it reproduces. A specie’s niche includes all of its interactions with the biotic and abiotic factors of its environment.

Question 8

transect

Answer 8

• commonly used in large areas to measure the distribution of a species, giving an idea of the variation that may occur in an area
• narrow strip that crosses and entire area being studies. one side to another
• provides and accurate and easy method of representing an area
• plan sketch (aerial view, shows to scale distribution of organisms in a measured and plotted view), profile sketch (side-on view, showing to scale the distribution of organisms along a line)

Question 9

quadrat

Answer 9

a quadrat is a piece of equipment used to identify a sample area and study the sessile (slow moving or non-moving) organisms within it
- provides 3 aspects of species distribution {species density, species cover, species frequency}
- provides limited information on the behaviour and interactions of organisms

Question 10

capture-mark-recapture

Answer 10

• helps determine number of animals in a population where it is impractical to count every individual

Question 11

distribution

Answer 11

a measure of where a population can be found

Question 12

abundance

Answer 12

a measure of the amount of individuals within a population

Question 13

sampling methods

Answer 13

It is more difficult to assess the distribution of animals due to their daily and seasonal movements. When assessing the animals in an ecosystem we can only observe evidence of their existence in the area.

Question 14

structure

Answer 14

because > thus > therefore

Question 15

symbiosis

Answer 15

a relationship/interactions in which two organisms live together in a close relationship
- Mutualism: relationship where both organisms benefit
- Parasitism: relationship where one organism benefits and the other suffers
- Commensalism: relationship where one organism benefits and the other is unaffected

Question 16

competition

Answer 16

when two or more organisms use one or more of the same resource and challenge each other for the use of the resource

Question 17

predation

Answer 17

a relationship in which one organism consumes another organism for energy

Question 18

graphs

Answer 18

x axis - independent (change)
y axis - dependent (measure)

Question 19

competition

Answer 19

interspecific = different/outside species
infraspecific = within same species