Unit 1 - Key Area 2 Flashcards Preview

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Flashcards in Unit 1 - Key Area 2 Deck (31)
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1

Competition between individuals belonging to two or more different species who have very similar resource requirements which are in short supply.

Interspecific competition

2

A stable plant community which is maintained by persistent human interference, such as burning and grazing

Plagioclimax

3

An animal that must meet its energy requirements by ingesting other organisms or organic matter derived originally from plants. Also known as a consumer

Heterotroph

4

Interactions between organisms which reduce the population when numbers are high and allow the population to increase when numbers are low. 

(factors include disease, predation, competition)

Density dependent

5

Succession that occurs on a pre-existing soil after primary succession has been disrupted or destroyed and the ecological community has been disturbed

Secondary succession

6

Population overshoot

A temporary situation that occurs when a population exceeds its carrying capacity, before lack of resources causes a population crash.

7

An animal that relies on external environments for temperature control instead of generating their own body heat.

Ectotherm

8

Net primary productivity (NPP)

The rate at which an ecosystem accumulates energy or biomass, excluding the energy used for the process of respiration.

NPP = GPP – respiration

9

The series of changes in an ecosystem when one community is replaced by another community as a result of changes in biotic and abiotic factors.

Succession

10

Predator–prey cycle

As a population of one species increases, its predator populations will increase in response. As the prey numbers fall due to predation, the predator numbers will also fall due to reducing resource availability.

11

What does this graph show?

A J-curve population 

 

-lag phase

-exponential growth

e.g. human population growth

12

A sudden decline in the numbers of individual members in a population, species or group of organisms, usually in response to scarcity of resources, intra-specific competition and/or other biotic factors

Population crash

13

The assimilation of food into new biomass through the transfer of organic material between trophic levels.

Secondary productivity

14

An animal that obtains its energy by consuming both plant and animal material

Omnivore

15

Any organism that gains its energy from other organisms. Also known as a heterotroph

Consumer

16

A relationship between species that helps to prevent overpopulation of a particular species to ensure the survival of the species as a whole

Interdependence

17

A level or position in a food chain, occupied by a group of organisms that have a similar feeding mode, ie autotrophs and heterotrophs (herbivores, carnivores, omnivores).

Trophic level

18

The stages of succession in an ecosystem advancing towards its climax community.

Seral stage

Examples of seres include xerosere, hydrosere, psammosere

19

What does this show?

S-curve population growth

-lag time

-exponential growth

-carrying capacity reached

20

The rate at which autotrophs (producers) produce a total biomass in a given area and time period.

Gross primary productivity (GPP)

21

Endotherm

An animal that uses internally generated heat to maintain body temperature independent of external temperature change.

22

The maximum population size of a species that the environment can sustain indefinitely.

Carrying Capacity

23

Density independent factor

Factors, usually natural disasters, which reduce the reproduction rate or increase the death rate of organisms independently of population density. (wild fires / droughts)

24

The percentage of biomass produced by one trophic level that is transferred and incorporated into biomass at the next trophic level.

Ecological efficiency

25

A measure of the rate at which new organic matter develops through photosynthesis

Primary productivity

26

An interaction that occurs between organisms whenever there is shared demand for a limited resource.

Competition

27

Climax communty

The final stage of succession, in which a community of plants and animals remains stable and exists in balance with each other and their environment.

28

The colonisation of a new site by communities of plants and animals after an event has removed all existing soil, for example glaciation or a lava flow. This type of succession must first wait for soil to develop sufficiently to support colonising species.

Primary succession

29

Intra-specific competition

Competition between individuals of the same species for the same limited resource

30

Parasitism

A symbiotic relationship between organisms of different species in which the host is a source of food and a habitat for the parasite.

 

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