chapter 11: Biodiversity

Question 1

what are the 3 ways of measuring biodiversity

Answer 1

habitat diversity
species diversity
genetic diversity

Question 2

define habitat diversity

Answer 2

the number of different habitats in an area
eg. could include dunes, woodlands and streams

Question 3

define species diversity

Answer 3

the number of species in an area (species richness)
the abundance of each species in an area (species evenness)

Question 4

define genetic variation

Answer 4

the variation of alleles within a species (or population)

Question 5

what are the ways of random sampling

Answer 5

random sampling - using quadrats, point quadrats, pitfall trap, kite net, pooter, tullgren funnel

Question 6

what are the non-random ways of sampling

Answer 6

systematic, opportunistic, stratified

Question 7

define species richness

Answer 7

the number of species found in a habitat
the more species present the richer the habitat
a simple count is not quantitative enough to give a measure of diversity as it does not count the number of individuals of each species

Question 8

define species evenness

Answer 8

counts relative numbers of abundance
numbers of species per unit area (frequency)

Question 9

what does simpsons diversity index measure

Answer 9

measures the diversity of a habitat, taking into account species richness and evenness

the higher the number the more diverse a habitat
a low value indicates low diversity - dominated by few species

Question 10

define gene

Answer 10

a section of DNA that codes for a protein

Question 11

define allele

Answer 11

an alternative version of a gene

Question 12

define gene locus

Answer 12

the place on a chromosome where a gene is found

Question 13

define monomorphic

Answer 13

only one version of a gene

Question 14

define polymorphic

Answer 14

two or more versions of a gene (alleles)

Question 15

how do you calculate the proportion of polymorphic gene loci

Answer 15

number of polymorphic gene loci /
total number of gene loci

Question 16

what factors affect biodiversity

Answer 16

human population growth
agriculture (monoculture)
climate change

Question 17

what are some reasons for maintaining biodiversity

Answer 17

ecological - protecting keystone species and maintaining genetic resources
economic - including soil depletion (continuous monoculture)
aesthetic - including protecting landscapes

Question 18

define in situ conservation

Answer 18

attempting to conserve species in its natural environment
eg. protected areas such as national parks and nature reserves

Question 19

define ex situ conservation

Answer 19

conserving species outside its normal environment
relocating to a safer place
eg. botanic gardens and breeding in captivity

Question 20

what are the advantages and disadvantages of in situ conservation

Answer 20

advantages - maintains natural ecosystems and evolutionary processes
allows you to protect multiply species at once
cheaper / more cost effective
allows the animals to remain in their natural habitat

disadvantages - still vulnerable to habitat destruction and external threats - cannot be fully safe

Question 21

what are the advantages and disadvantages of ex situ conservation

Answer 21

advantages - offers high level of protection from immediate threats
allows for research and breeding programmes

disadvantages - can be expensive to set up and maintain
may not replicate natural habitats well
animals may not adapt well to new environment
can only be suitable for small populations of species eg. zoos and seed banks

Question 22

what is the convention on International Trade in Endangered Species (CITES)

Answer 22

regulate and monitor international trade
ensures international trade does not endanger the survival of wild populations
ensure that trade in wild plants is prohibited for commercial purposes

Question 23

what is the Rio Convention on Biological Diversity

Answer 23

signed in 1992 by 150 countries
promotes sustainable development

Question 24

what is the countryside stewardship scheme

Answer 24

local conservation agreement
introduced in 1991
paid land owners to manage land for biodiversity
eg. regenerate hedgerows
leave grassy margins for wildflowers
graze upland areas to reduce bracken

Question 25

what are the benefits of genetic biodiversity

Answer 25

allows for adaptation to changing environment
provides variation for natural selection
can offer, camouflage / protection from predators

Question 26

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

Answer 26

dig hole and place container in soil ✓
make top of container level with soil level ✓
cover to protect from, rain / scavengers ✓
leave overnight ✓
identify / count, (named) invertebrates ✓
sample both areas, randomly / at 5(+) sites ✓
3 max

Question 27

how can you improve accuracy of an experiment

Answer 27

increase number of samples
repeat/ replicate the entire experiment again

Question 28

suggest the advantages of conserving plant species as seeds and not as adult plants

Answer 28

can be collected with minimal damage to the wildlife
take up little space - can conserve a larger population
can store greater genetic diversity
lower maintenance/ manpower costs
easier/ cheaper to transport and collect
remain viable for longer periods of time
less susceptible to disease/ pests

Question 29

outline the consequences of a habitat having a low Simpson’s index of diversity

Answer 29

habitat dominated by one/ few species

change in one species is more likely to effect the whole habitat

ecosystem not able to withstand change/ easily damaged de

Question 30

define biodiversity

Answer 30

the range of species within an area
range of habitats/ ecosystems
variety of genes/ alleles