On The Wild Side

Question 1

Biosphere

Answer 1

The part of the Earth and its atmosphere that is inhabited by living organisms

Question 2

Abiotic factors definition

Answer 2

Physical and chemical factors (soil type, climate)

Question 3

Biotic factors definition

Answer 3

Factors determined by organisms (density dependent: related to the size of the population relative to area available)

Question 4

Why does a particular species live in a particular area?

Answer 4

Because it is adapted and is able to survive and reproduce there. (or it was deliberately introduced and maintained by humans)

Question 5

Abiotic factors examples:

Answer 5

Solar energy input

Climate

Topography (altitude, slope, aspect)

Oxygen availability

Edaphic factors (soil factors)

Pollution (air, water, land)

Catastrophes (earthquakes, floods, volcanic eruptions, fires)

Question 6

Biotic factors example:

Answer 6

Competition

Grazing, predation, parasitism (one organism benefits another in this relationship)

Mutualism (relationship where both partners benefit)

Question 7

What may there be competition for?

Answer 7

Food, water, light, space

Interspecific or intraspecific

Question 8

What is solar energy input affected by?

Answer 8

Latitude, season, cloud cover, changes in the Earth’s orbit

Question 9

When is oxygen availability particularly important?

Answer 9

In aquatic systems (eg fast flowing streams better oxygenated than stagnant pools)

Question 10

What are edaphic factors and what are they affected by?

Answer 10

Factors relating to soil: pH, mineral salt availability, soil texture,

Affected by geology

Question 11

What are anthropogenic factors?

Answer 11

Factors arising from human activity (biotic or biotic)

The impact of humans on the world environment is far greater than that of any other species.

Question 12

Examples of anthropogenic factors:

Answer 12

Deforestation, grazing, moor/burning

Question 13

Adaptations of a polar bear:

Answer 13

Thick fur - insulation

Long oily outer hairs - easily shed water
Finer inner hairs - provide insulation by trapping air

Small ears and tail

Long nose w several passages

Thick layer of fat under skin

Question 14

Why can the tundra grasses better withstand grazing than other tundra vegetation?

Answer 14

(All grass) grow from the base, rather than the tips

Question 15

What is the tundra?

Answer 15

The worlds most northerly land ecosystems where the tree growth is hindered by very low temperatures. Not a lot of rain or wind.

(In the Arctic and tops of mountains are tundra ecosystems)

Question 16

Succession

Answer 16

The ecological process in which one community progressively changes into another.

(Eg The first organisms to colonise bare rock, for example, are algae and lichens - they’re the only organisms which can survive in the demanding conditions, they start to break up the rock surface allowing organic material to accumulate and soil to form…in this way they change the habitat and make it suitable for other species)

Question 17

Primary succession

Answer 17

Starts in newly formed habitats where there has never been a community before

Question 18

Pioneer species

Answer 18

First organisms to colonise a newly formed habitat/ a habitat that has been cleared of vegetation

(the only species that can cope w the demanding conditions eg extremes of temperature, lack of soil)

Question 19

What are the pioneer species on bare rock?

Answer 19

Lichens and algae

Question 20

Climax community

Answer 20

The different species of organisms that make up the final stage of an ecological succession.
(The nature of the climax community depends on environmental conditions eg climate)

Question 21

Secondary succession

Answer 21

A succession which starts where an existing community has been cleared.

Eg Successions that start after fires

Question 22

Deflected succession

Answer 22

A community that remains stable only because human activity prevents succession from running its course.
Eg sheep grazing prevents grassland to develop into woodland