Biodiversity -Module 4

Question 1

what is biodiversity

Answer 1

-the veriety of living organisms, genetic diversity, and habitats in an area

Question 2

what is a habitat

Answer 2

a place where an organism lives

Question 3

what is a species

Answer 3

a group of similar organisms that are capable of breeding to produce fertile offspring

Question 4

3 levels of biodiversity

Answer 4

1. Habitat diversity: (abiotic biotic)
2. species diversity: (richness + evenness)
3. Genetic diversity: (variation of alleles)

Question 5

what is an allele

Answer 5

The version of a gene

Question 6

locus (genes)

Answer 6

The position of the gene on a chromosome

Question 7

polymorphism

Answer 7

a locus with 2 or more alleles

Question 8

how is genetic diversity calculated

Answer 8

-genetic polymorphism is used.
-proportion of polymorphic gene loci in a population indicates the level of genetic diversity

-proportion of polymorphic gene loci = no. of polymorphic gene loci/total no. of gene loci

Question 9

stratified sampling

Answer 9

The population or habitat is divided into subgroups and a sample is taken proportionally to the size of that group

Question 10

opportunistic sampling

Answer 10

The investigator selects the samples as it is simple to carry out, however it is biased

Question 11

systematic sampling

Answer 11

Samples are taken at fixed intervals, often along a line. This could be a transect

Question 12

issues with animal sampling

Answer 12

-animals move
-disturbing habitats- need to trap animals
–cannot trap large animals

Question 13

what does it mean if the diversity index of the Simpsons diversity index is low

Answer 13

the area may be dominated by one or a few species. environment may be hostile, and only a few organisms are well adapted to it. environmental change may effect the whole habbitat

Question 14

if the Simpsons diversity index is high:

Answer 14

suggests a number of successful species, a less hostile environment and many ecological niches available. A change to the environment should have less effect on the habitat

Question 15

how is Human population growth affecting biodiversity

Answer 15

Human population growth
Habitat loss due to the need for more land for housing and food destroys habitats e.g deforestation in amazon decreases habitat & species diversity
Over-exploitation of resources resources used up faster than can be replenished industrial fishing decreasing genetic & species diversity
Urbanisation  cities and road developments can isolate species which would then show lower genetic diversity as can’t breed with others of the species
Pollution-> more waste & pollution which can kill species and destroy habitats e.g fertiliser/ gases causing acid rain

Question 16

Monoculture affecting biodiversity

Answer 16

Monoculture- the growing of a single variety of a single crop
Habitat loss land is cleared to make room for large fields/fish farms
Removal of hedgerows often done to use large machinery and increase space
Loss of local plants and animals often seen as weeds/pests so destroyed using pesticides/herbicides reducing species diversity
Loss of heritage(traditional) varieties of crop-> often don’t make enough money so aren’t planted which reduces species diversity

Question 17

Climate change

Answer 17

significant long term change in an area’s climate`

Question 18

how does climate change effect biofiversity

Answer 18

Change in climate can mean that an area becomes inhabitable could decrease biodiversity
Change migration patterns could lead to extinction

Question 19

what is species richness

Answer 19

no. of different species living in a specific area

Question 20

species evenness

Answer 20

the number of individuals within the species living in a community

Question 21

compare biodiversity of an arid desert to a temperate coastline

Answer 21

habitat diversity: desert = low , coastline = high
Species diversity: desert = low, coastline = high

Question 22

why does genetic diversity increase a species’ chance of long term survival

-examples with a consequence

Answer 22

-Greater genetic variation -therefore more likelihood some organisms suited to habitat change
-examples with a consequence
e.g: some organisms will be better adapted to avoid new predators - therefore less chance of being killed

Question 23

difference between random and non random sampling

Answer 23

random = organisms have same likelihood of being selected
non random - different organisms have higher/ lower probabilities of being selected

Question 24

describe how you can increase the likelihood of a sample being a reliable representation of the population as a hole

Answer 24

-use random sampling
-remove sampling bias
-use as large a sample size as possible
-removes the effects of chance

Question 25

what type of sampling would you use to study how organisms differ throughout the length of a stream
why

Answer 25

systematic sampling
-abiotic conditions vary as you travel downstream affecting the type and abundance of organisms present

Question 26

what type of sampling would you use to study the distribution of organisms on a school field

why

Answer 26

Random sampling
-environment easy to study / fairly uniform
-reduces sample bias / increases reliability

Question 27

what is species richness

Answer 27

number of different species living within an area

Question 28

what is genetic biodiversity

Answer 28

The genetic diversity within a species is the diversity of alleles and genes in the genome of species

Question 29

what is species evenness

Answer 29

A comparison of the numbers of individuals of each species in a community