More on biodiversity

Question 1

What is genetic diversity?

Answer 1

Genetic diversity is the VARIATION of ALLELES within a SPECIES (or within a population of a species)

Question 2

What would happen if a population has a LOW GENETIC DIVERSITY?

Answer 2

If a population has a low GENETIC DIVERSITY, they may not be able to ADAPT to a CHANGE IN ENVIRONMENT and the WHOLE POPULATION could be WIPED OUT by one single event. E.g. disease.

Question 3

What type of population may have a low genetic diversity?

Answer 3

Populations in which genetic diversity may be low include ISOLATED POPULATIONS such as those bred in CAPTIVITY (e.g. in zoos, and pedigree animals and rare breeds).

Question 4

What can be used to MONITOR the genetic diversity of a population?

Answer 4

Calculations can be used to MONITOR the GENETIC DIVERSITY of these populations over time and efforts can be made to INCREASE the genetic diversity of the population if needed. E.G. BREEDING PROGRAMMES in ZOOS are very closely managed to maximise genetic diversity.

Question 5

What is a pedigree animal?

Answer 5

A pedigree animal is one that has been bred purely from animals of the same breed.

Question 6

What is a rare breed?

Answer 6

A rare breed is usually a breed of farm animal that’s not used in large scale farming.

Question 7

What are alleles?

Answer 7

alleles of the same GENE are found at the same point (called a locus) on a chromosome.

Question 8

What does POLYMORPHISM mean?

Answer 8

Polymorphism describes a locus that has two or more alleles.

Question 9

What is the significance of working out the proportion of the polymorphic gene loci.

Answer 9

Working out the PROPORTION of the POLYMORPHIC GENE LOCI in an organism (i.e those points on a chromosome which can have more than one allele) gives you a measure of GENETIC DIVERSITY.

Question 10

Formula used to find proportion of the the polymophic gene loci.

Answer 10

Proportion of the polymorphic gene loci = no. of polymorphic gene loci/ total number of loci. (remember)

E.g if 40 of the genes sampled in a population are polymophic out of a 100 genes sampled in total, the the proportion of the polymorphic gene loci = 40/100 =0.4 (reminder)

Question 11

The human population of the planet has grown hugely in the last couple of centuries and is continuing to rise.
This is DECREASING GLOBAL BIODIVERSITY because of the following factors:

Habitat loss, explain?

Answer 11

Habitat loss- Human development is DESTROYING HABITATS, e.g. there is deforestation in the Amazon to make way for grazing and agriculture.
This decreses habitat diversity.

Question 12

The human population of the planet has grown hugely in the last couple of centuries and is continuing to rise.
This is DECREASING GLOBAL BIODIVERSITY because of the following factors:

Over explotation, explain?

Answer 12

Over-explotation- a Great demand for RESOURCES (such as food,water and energy) means a lot of resources are being USED UP FASTER than they can be REPLENSHIED.

E.g. industrial fishing can deplete the population of certain fish species and may even cause extinction (a species to die out).

This decreases genetic diversity within populations, as well as decreasing species diversity (as a result of extinction).

Question 13

The human population of the planet has grown hugely in the last couple of centuries and is continuing to rise.
This is DECREASING GLOBAL BIODIVERSITY because of the following factors:

Urbanisation, explain?

Answer 13

Urbanisation- Sparwling cities and major road developments can ISOLATE SPECIES, meaning populations are unable to INTERBREED and GENETIC DIVERSITY is DECREASED.

Question 14

The human population of the planet has grown hugely in the last couple of centuries and is continuing to rise.
This is DECREASING GLOBAL BIODIVERSITY because of the following factors:

Pollution, explain?

Answer 14

Pollution - High amounts of POLLUTANTS can KILL SPECIES or destroy habitats,e.g. high level of FERTILISERS flowing into a river can lead to a DECREASE in FISH SPECIES in that RIVER. This decreases biodiversity.

Question 15

In order to FEED an evergrowing number of people. large areas of land are devoted to MONOCULTURE - the growing of a SINGLE VARIETY of a SINGLE CROP. E.g. in Africa, large areas of land are being used for palm oil plantations. This leads to a decline in global diversity because of the folowing factors:

Habitat, explain?

Answer 15

Habitats are LOST as the LAND is CLEARED to make way for large fields, reducing habitat diversity.

Question 16

In order to FEED an evergrowing number of people. large areas of land are devoted to MONOCULTURE - the growing of a SINGLE VARIETY of a SINGLE CROP. E.g. in Africa, large areas of land are being used for palm oil plantations. This leads to a decline in global diversity because of the folowing factors:

Local plants and animals, explain?

Answer 16

Local and naturally occurying PLANTS and ANIMALS are seen as WEEDS and PESTS, and so are destroyed by pesticides and herbicides, reducing species diversity.

Question 17

In order to FEED an evergrowing number of people. large areas of land are devoted to MONOCULTURE - the growing of a SINGLE VARIETY of a SINGLE CROP. E.g. in Africa, large areas of land are being used for palm oil plantations. This leads to a decline in global diversity because of the folowing factors:

Heritage (traditional) varieties of crops, explain?

Answer 17

Heritage (traditional) varieties of crops are lost because they dont make enough money and so are not planted anymore, which reduces species diversity.

Question 18

What is climate change?

Answer 18

Climate change is the VARIATION of the earths climate, e.g. things like change in temperature and rainfall patterns

Question 19

Climate change is mostly due to humans, explain why?

Answer 19

It occurs NATURALLY, but the SCIENTIFIC CONSENSUS is that the climate change we’re experiencing at the moment is caused by humans increasing emissions of greenhouse gases (such as carbon dioxide)

Question 20

Climate change will affect DIFFERENT AREAS of the world, in different ways, such as?

Answer 20

Some places will get WARMER, some COLDER, some WETTER, and others DRIER.. All of these are likely to affect GLOBAL BIODIVERSITY.

Question 21

Most species need a particular … to survive.

Answer 21

Climate

Question 22

A change in climate may mean?

Answer 22

A change in climate may mean that an area that was previously INHABITABLE becomes UNINHABITABLE. (Vice Versa)

Question 23

A change in habitats could disturb the species living there, explain?

Answer 23

This may INCREASE or DECREASE in the RANGE of some species (the area in which they live). This could increase or decrease biodiversity.

Question 24

Pro and con for species migrating to a diffeent area.

Answer 24

Some species may be forced to MIGRATE to a more sutable area, causing a change is species distribution.

Migration usualy DECREASES biodiversity in the areas the species migrate from, and INCRASE bioversity in the areas they migrate to.

Question 25

Climate change could be drastic and cause species to die out, how?

Answer 25

If there isnt a suitable habitat to migrate to, the species is a plant and CAN’T MIGRATE, or if the change is TOO FAST, the species may become EXTINCT. This will decrease biodiversity.

Question 26

In a population of species A, a sample of 80 gene loci were tested for polymorphism. 36 of the genes were found to be polymorphic.
What is the proportion of the polymorphic gene loci in this sample?

Answer 26

0.45

Question 27

Describe how human population growth and monoculture during the last 30 years could have decreased global biodiversity.

Answer 27

Human population growth leads to more human development, which destroys habitats, decreasing habitat diversity.

There is a great demand for resources, which can lead to resources being used up faster than they can be replenished, decreasing genetic diversity and species diversity.

Urbanisation can isolate species, meaning populations are unable to interbreed, decreasing genetic diversity.

High amounts of pollutants can kill species or destroy habitats, decreasing biodiversity.

Monoculture leads to a loss of habitats and habitat diversity as land is cleared for large fields.

etc…