Module 4: Biodiversity

Question 1

Define biodiversity.

Answer 1

Variety of living organisms in an area.

Question 2

Define species.

Answer 2

A group of similar organisms able to reproduce to give fertile offspring.

Question 3

Define habitat.

Answer 3

The area inhabited by a species, including abiotic and biotic factors.

Question 4

What is habitat diversity?

Answer 4

The number of different habitats in an area.

Question 5

What is species diversity?

Answer 5

The number of different species in an area.

Question 6

What is genetic diversity?

Answer 6

The variation of alleles within a species/population.

Question 7

What is a pitfall trap?

Answer 7

A small pit that insects can’t get out of.

Question 8

What organism would a pitfall trap be used for?

Answer 8

Crawling ground insects.

Question 9

What is a pooter?

Answer 9

A device that allows you to safely suck small insects through a tube in a jar.

Question 10

What organism would a pooter be used for?

Answer 10

Crawling ground insects.

Question 11

How does a Tullgren funnel work?

Answer 11

*a soil or leaf litter sample is put on a mesh filter at the top of a funnel
*light is shone down onto it
*organisms move away from the heat and fall out of the funnel into a collecting beaker

Question 12

What organisms would a Tullgren funnel be used for?

Answer 12

Small ones that live in soil or leaf litter.

Question 13

What is kick sampling?

Answer 13

Gently kicking the bottom of a stream and using a net to collect the disturbed organisms.

Question 14

What is sweep sampling?

Answer 14

Sweeping a sweep net through long grass.

Question 15

What is a sweep net?

Answer 15

A net lined with strong cloth on a pole.

Question 16

What is one way a random sample can be taken?

Answer 16

*divide the field into a grid using tape measures
*use a random number generator to select coordinates

Question 17

What are the three types of non-random samples?

Answer 17

*systematic
*opportunistic
*stratified

Question 18

What is systematic sampling?

Answer 18

When samples are taken at fixed intervals.

Question 19

Give an example of systematic sampling.

Answer 19

To count plant species in a field, place quadrats along a line (transect).

Question 20

What is opportunistic sampling?

Answer 20

When samples are chosen by the investigator.

Question 21

What is a problem with opportunistic sampling?

Answer 21

The data will be biased.

Question 22

What is statified sampling?

Answer 22

When different areas in a habitat are identified and sampled separately in proportion to their part of their habitat as a whole.

Question 23

What is species richness?

Answer 23

The number of different species in an area.

Question 24

What is species evenness?

Answer 24

A measure of the relative abundance of each species in an area.

Question 25

What is Simpson's Index of Diversity used for?

Answer 25

Measuring diversity, taking into account species richness and eveness.

Question 26

What is the formula for Simpson's Index of Diversity?

Answer 26

D = 1-(Σ(n/N)^2)

Question 27

What does the n mean in Simpson's Index of Diversity?

Answer 27

Total number of individuals of one species.

Question 28

What does the N mean in Simpson's Index of Diversity?

Answer 28

Total number of organisms of all species.

Question 29

What is Simpson's Index of Diversity value always between?

Answer 29

0 and 1

Question 30

What does it mean if Simpson's Index of Diversity is closer to 1?

Answer 30

The more diverse the habitat is (greater species richness and evenness).

Question 31

What does it mean if a population has low genetic diversity?

Answer 31

They might not be able to adapt to a change in the environment and the whole population could be wiped out by a single event.

Question 32

Give examples of populations that might have low genetic diversity.

Answer 32

Isolated populations - those bred in captivity: *zoos *pedigree animals *rare breeds

Question 33

What is a locus on a chromosome?

Answer 33

The point where the alleles are found.

Question 34

What is polymorphism?

Answer 34

A locus that has two or more alleles.

Question 35

What does working out proportion of polymorphic gene loci in an organism give you?

Answer 35

A measure of genetic diversity.

Question 36

What is the formula for proportion of polymorphic gene loci?

Answer 36

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

Question 37

What are the three main factors affecting biodiversity?

Answer 37

*human population growth *increased use of monoculture *climate change

Question 38

What are the four ways human population growth has decreased global biodiversity?

Answer 38

*habitat loss *over-exploitation *urbanisation *pollution

Question 39

How has habitat loss decreased biodiversity?

Answer 39

Destroying habitats (e.g. deforestation).

Question 40

What type of diversity does habitat loss decrease?

Answer 40

Habitat diversity.

Question 41

How has human population growth increased over-exploitation?

Answer 41

*greater demand for resources *resources being used up faster than they can be replenished

Question 42

What types of diversity does over-exploitation decrease?

Answer 42

*genetic diversity *species diversity

Question 43

How does urbanisation decrease biodiversity?

Answer 43

*sprawling cities and major road developments can isolate species *populations are unable to interbreed

Question 44

What type of diversity does urbanisation decrease?

Answer 44

Genetic diversity.

Question 45

How does pollution decrease biodiversity?

Answer 45

High amounts of pollutants can kill species or destroy habitats.

Question 46

What is monoculture?

Answer 46

The growing of a single variety of a crop.

Question 47

How does monoculture decrease habitat biodiversity?

Answer 47

Habitats are lost as land is cleared for large fields.

Question 48

How does monoculture decrease species biodiversity?

Answer 48

*local and naturally occurring plants and animals are seen as weeds and pests, so are destroyed with pesticides and herbicides *heritage (traditional) varieties of crops are lost because they don't make as much money and aren't planted

Question 49

How does climate change causes increases and decreases in biodiversity?

Answer 49

*most species need a particular climate to survive *a change in climate may mean a previously inhabitable area becomes uninhabitable *increase or decreases range of some species

Question 50

How does climate change effect species biodiversity?

Answer 50

*some species forced to migrate to a more suitable area *changes species distribution *increases biodiversity in areas they migrate to *decreases biodiversity in areas they migrate from

Question 51

How does climate change decrease biodiversity?

Answer 51

*if there isn't a suitable habitat to migrate to, the specie is a plant or the change is too fast *species may become extinct