Module 4 - Biodiversity

Question 1

Explain the importance of sampling in measuring the biodiversity of a habitat

Answer 1

Sampling provides an estimate of the number of species in an area as counting every individual is difficult and time consuming

Question 2

Why is it important to take samples in fenced and unfenced areas

Answer 2

To compare two areas

Question 3

Explain the difference between species richness and species evenness and why both measurements are needed to assess biodiversity.

Answer 3

Species richness is the number of species in a habitat
Species evenness is the number of individuals in each species
Higher biodiversity is associated with both species riches and species evenness

Question 4

Outline the significance of a low value of Simpson’s Index of Diversity

Answer 4

Low value of simpsons index of diversity suggests that there is a small variety of species therefore the ecosystem is unstable and are less likely to cope with change

Question 5

What is the equation for the proportion of polymorphic gene loci?

Answer 5

Proportion of polymorphic gene loci = number of polymorphic gene loci / total number of loci

Question 6

Give one aim of CITES

Answer 6

Conserves the endangered species by regulating trading activities

Question 7

Define the term species evenness

Answer 7

The relative abundance of each species in an area

Question 8

Name the agreement that encourages fair sharing of benefits from the legal use of endangered species

Answer 8

Rio Convention

Question 9

What best describes the term biodiversity?

Answer 9

The variety of genes, species and habitats

Question 10

The cassowary is a large, flightless bird found in the rainforest in parts of Australia. It feeds mainly on fruit. The seeds of the fruit are deposited on the rainforest floor.

The cassowary is known as a keystone species. This means it is important for the survival of other species.

Suggest what role the cassowary plays in the survival of other species.

Answer 10

Seed Dispersal

Question 11

The cassowary needs to be conserved for ecological reasons.

State two other reasons for maintaining biodiversity.

Answer 11

Brings more economy due to tourism visiting the bird

The bird is aesthetically pleasing to view

Question 12

The mountain gorilla is an endangered species with as few as 880 individuals surviving in the wild. Many of the animals have been ‘habituated’ to human contact. The health of these animals is monitored and medical assistance is given when necessary. Animals that are not habituated are rarely visited.

(i) Suggest one advantage and one disadvantage of keeping some gorilla families that have not been habituated.

Answer 12

Advantage:
less likely to catch disease from humans

Disadvantage:
Poaching is more likely

Question 13

What was the Rio Convention about

Answer 13

Agreement between nations

develop national strategies for sustainable development and maintaining biodiversity.

Question 14

D sumatrensis lives in rainforests.
Their numbers are difficult to determine but they are estimated to number fewer than 100.
Suggest two reasons why this species is critically endangered in the wild.

Answer 14

Due to loss of habitat as mass deforestation and hunting is occurring.

Question 15

The remaining D sumatrensis are all small and are scattered in isolated areas.
These are factors that might speed up the extinction of the species.
Suggest why

Answer 15

Natural disaster can wipe out small populations

More vulnerable to predators

Question 16

Suggest one other way in which zoos can contribute to the conservation of organisms

Answer 16

Educating and raising awareness

Question 17

Global biodiversity is in decline.
Human population growth, agriculture and climate change each have an effect upon biodiversity.
Explain how each of these factors contributes to the decline in biodiversity.

Answer 17

Human population growth can affect biodiversity as there is a demand in more housing and land therefore more habitats are destroyed to clear the land. In addition more pollution is produced causing damage to wildlife.

Agriculture can affect biodiversity as planting one plant for profit can lower the biodiversity. Using pesticide and fertiliser causes one plant to grow however damages surrounding species. This suggests that there is a lower capacity to cope to changing conditions.

Climate change lowers biodiversity as a rise in sea level due to glaciers melting causes more frequent flooding which in turn damages crops and reduces land area. In addition, some species may not be able to adapt.

Question 18

Explain the benefits to agriculture of maintaining plant biodiversity.

Answer 18

used for genetic engineering;
variety of plants might be useful (climate change)
source of a new medicine for livestock

Question 19

Under the terms of one such agreement, some of the money made legally from endangered species goes to the country where the species was first discovered in the wild.

Name the agreement that encourages fair sharing of benefits from the legal use of endangered species.

Answer 19

Rio Convention

Question 20

Explain why it is sometimes necessary to conserve a plant species, such as N. thermarum, outside its natural habitat (ex situ).

Answer 20

habitat can be destroyed from climate change or human activity
Ex situ can maintain a gene pool
Protection from disease

Question 21

Give three advantages of conserving plant species as seeds and not as adult plants.

Answer 21

Lower maintenance costs
Large numbers can be stored
Easy to transport

Question 22

Female silver-washed fritillary butterflies, Argynnis paphia, are usually an orange-brown colour. However, a deep olive-green colour can be seen in some females, largely in the south of England.

What is the term given to this type of biodiversity?

Answer 22

genetic biodiversity

Question 23

Explain how a pitfall trap can be set up and used to sample invertebrate biodiversity.

Answer 23

dig hole and place container in soil 
Make container level to the  soil 
cover to protect 
leave over night 
and count number of invertebrates the next morning

Question 24

Explain one way in which tourists can lead to an increase in the biodiversity of an area.

Answer 24

Ecotourism

Money from tourism is used to support conservation

Question 25

State the collective name of the animal and plant populations that are present at the end of primary succession

Answer 25

Climax Community

Question 26

The aim of the survey was to compare the biodiversity of butterfly species in the two areas
Suggest how the procedure could be improved so that a valid comparison could be made

Answer 26

More transects in different parts of area 1 and 2
Different times of day
Method of ensuring individuals are not counted again

Question 27

Botanic gardens collect plant species from around the world to maintain biodiversity
State two levels at which biodiversity may be considered

Answer 27

Genetic

Number of Species

Question 28

Outline briefly a valid investigation that could determine the effect of varying the moisture content of the soil on the growth of a plant

Answer 28

grow in a range of water content
leave for same time
measure height
calculate mean

Question 29

Scientists try to estimate the total number of species on earth
Suggest 3 reasons why estimates are not likely to be accurate

Answer 29

Not all species found
Some may be extinct recently
New species are being formed

Question 30

Explain what a keystone species is

Answer 30

have significant effect on ecosystem

many other species rely on activity of the specific animal

Question 31

Current estimates of the Scottish wildcat population vary
Biodiversity occur only in the most remote, uninhabited areas of the Scottish Highlands.
Biodiversity can be considered at several levels. A scientist concluded that the biodiversity of the Scottish highlands would continue to reduce because of the small population of Scottish wildcats.

Evaluate the scientists conclusion with reference to genetic biodiversity and species biodiversity. (6)

Answer 31

genetic diversity will decrease, there will be smaller gene pool and smaller proportion of polymorphic loci. In breeding is more likely and cats are more closely related therefore lower potential for adaptation .

species biodiversity, wildcats may go extinct. It can affect food chain. Species richness can decrease as one less species.