Biodiversity 2

Question 1

Define population

Answer 1

Total number of organisms of one species that occupy the same ecosystem at the same time

Question 2

Define abiotic factor

Answer 2

Non-living factor in a particular area

Question 3

Define biotic factor

Answer 3

Living factor in a particular area

Question 4

Define carring capacity

Answer 4

The size of population of a species that an ecosystem can support

Question 5

Define limiting factors

Answer 5

Factors which limit the growth of the population or organism

Question 6

How does high temperatures influence population size

Answer 6

Enzymes activity increases. Metabolic rate increases. Carring capacity increases. More energy available for growth and repair. If temperatures too high then enzymes denature

Question 7

How does low temperatures influence population size

Answer 7

. Enzymes activity reduced
. Metabolic rate reduced
. Carring capacity is reduced
. More energy used to maintain body temperature so less energy for growth and repair

Question 8

How does a high light intensity influence population size

Answer 8

. Photosynthesis rate increase
. Faster plant growth/ reproduction
. Greater population size
. Carrying capacity is increased
More food available for other organisms
. More variety of food sources available

Question 9

How does low light intensity influence population size

Answer 9

. Photosynthesis decreases
. Slower plant growth/ reproduction
. Smaller population size
. Carrying capacity decreases
. Less food available for other organisms

Question 10

How does a high pH influence population size

Answer 10

. Enzymes activity reduced
. Metabolic rate reduces
. Carrying capacity reduced
. Enzymes denature

Question 11

How does a low pH influence population size

Answer 11

. Enzyme activity reduced
. Metabolic rate reduced
. Carrying capacity reduced
. Enzyme denature

Question 12

How does a decrease in water availability influence population size

Answer 12

Populations are reduced, only specially adapted species can live there

Question 13

How does a low humidity influence population size

Answer 13

Increased transpiration rate in plants and evaporation of water from animals bodies

Question 14

Define niche

Answer 14

Role/ position of organisms within the habitat

Question 15

Explain why 2 species never occupy exactly the same niche

Answer 15

. Interspecific competition for factors
. E.g food sources
. One species becomes extinct

Question 16

Explain what happens when a niche overlaps

Answer 16

. Interspecific competition
. One species/ population more successful
. Species extinct

Question 17

Define intraspecific competition

Answer 17

Competition between organisms of the same species for the same reasources

Question 18

Define interspecific competition

Answer 18

Competition between organisms of a different species for the same resource

Question 19

What are the roles of the pioneer species

Answer 19

. Increases humus/ organic content in the soil
. Increase water retention
. Increase habitats
. Decreases soil erosion

Question 20

What are the features of pioneer species

Answer 20

. A sexual reproduction so single organisms can rapidly multiply
. Rapid germination
. Have increased photosynthesis- as no other food source available

Question 21

Describe stage 1 of succession

Answer 21

. Pioneer species
. (Name the species)
. Lives in hostile area

Question 22

Describe stage 2 of succession

Answer 22

. Increases humus organic content of the soil
. Increase water retention in soil
. Increase habitat variety
. Decrease soil erosion

Question 23

Describe stage 3 of succession

Answer 23

. Nitrigen- fixing bacteria
. Greater water retention
. More stable
. More humus

Question 24

Describe the climax community of succession

Answer 24

. Increase biodiversity
. Greater biomass