A Local Ecosystem

Question 0

What are the abiotic characteristics of terrestrial environments?

7.

Answer 0

The availability of oxygen
Temperature
Pressure variation
Viscosity
Light penetration
Buoyancy
Availability of ions

Question 1

What are the abiotic characteristics of an aquatic environment?

6.

Answer 1

The availability of oxygen
Temperature
Pressure variation
Viscosity
Light penetration
Availability of ions

Question 2

What are some factors that determine distribution and abundance?

4.

Answer 2

Climate
Availability of food
Shelter
Interactions between organisms

Question 3

What is the role of photosynthesis?

Answer 3

Photosynthesis is the chemical reaction carried out by plants to produce energy. Without photosynthesis there would be no energy or carbohydrates for the growth and reproduction of organisms to sustain life.

Question 4

What is the formula for photosynthesis?

Answer 4

Carbon dioxide + Water = Glucose + Oxygen

Question 5

What is the role of respiration?

Answer 5

It is a biochemical process. It converts the energy stored in the glucose molecule into an easily accessible chemical energy source.

Question 6

What is the respiration formula?

Answer 6

Glucose + Oxygen = Carbon Dioxide + Water + Energy

Question 7

How is energy used in ecosystems?

5.

Answer 7

Growth
Repair and maintenance
Muscle contraction and movement
Specialised cell functions
Reproduction

Question 8

What factors can vary population size?

4.

Answer 8

Birth rate
Death rate
Immigration
Emigration

Question 9

What do the numbers of predators and prey depend upon?

6.

Answer 9

The size of an ecosystem
The availability of food
The reproductive cycles of both organism
Competition from other predators
Disease amongst one species
Seasonal migrations of either species

Question 10

What is mutualism?

Answer 10

Both species benefit from the association

Question 11

What is commensalism?

Answer 11

The presence of one species has a beneficial impact on the other, but is not itself affected by the association

Question 12

What is exploitation?

Answer 12

One species benefits at the expense of another

Question 13

What is parasitism?

Answer 13

Involves one species living on or in a host, The organism benefits while the host is harmed but not usually killed

Question 14

What is allelopathy?

Answer 14

One species benefits by producing a compound which restrains the growth of another organism

Question 15

What is the role of a decomposer in an ecosystem?

Answer 15

They act to breakdown dead or decaying organic matter, so releasing important minerals back into the soil.

Question 16

Describe trophic interactions.

Answer 16

Energy passes from one trophic level to another. Plants occupy the first trophic level. Energy passes to the next trophic level when plants are consumed by herbivores. Most food chains consist of only 3 or 4 trophic levels. 80 to 90% of energy from each level is lost as heat.

Question 17

What is an adaption?

Answer 17

And adaption is a feature of an organism that makes it suited to its environment.

Question 18

What are the effects of competition?

1.
4.

Answer 18

SHORT TERM
Re-sources will decrease. If one species has an advantage over the other it will limit the growth of another population.

LONG TERM
Degradation of the environment
Diversity may be reduced
Extinction
Evolution

Question 19

What are the impacts humans have on ecosystems?

5.

Answer 19

Land clearing
Salination
Pollution
Introduced species
Depletion of resources