4.2 Biodiversity

Question 1

What is the difference between species richness and species evenness?

Answer 1

(species) richness is number of species (in a habitat) ;
(species) evenness is , abundance / number of
individuals of , each / every / all , species (in a habitat)

Question 2

What are the four types of sampling?

Answer 2

Random
Oppertunistic- prior knowledge
Stratified- broken up
Systematic- regular intervals

Question 3

Define biodiversity

Answer 3

range / variety / number , of species (in an area) ;
range / variety of, habitats / ecosystems ;
variety of , alleles / genes ;

Question 4

define species

Answer 4

organisms that can freely interbreed to produce fertile offspring

Question 5

what are the 3 types of biodiversity?

Answer 5

habitat
species
genetic

Question 6

what is habitat biodiversity?

Answer 6

the range of habitats in which different species live

Question 7

what is species biodiersity?

Answer 7

Difference between species
This could be within a habitat, or a community
Differences could be structural or physical

Question 8

what is genetic biodiversity?

Answer 8

variation between individuals belonging to the same species

Question 9

What is habitat sampling (2)

Answer 9

small portion of a habitat is selected and studied carefully.
You can then multiply up the numbers of individual species found to give an estimate for the entire habitat.

Question 10

what is random sampling

Answer 10

randomly select sample sites by randomly generate numbers as coordinates

Question 11

what is one advantage and one disadvantage of random sampling?

Answer 11

ensures data isn’t biased

may not cover all areas equally

Question 12

what are the 3 types of non-random sampling?

Answer 12

oppertunistic
stratified
systematic

Question 13

what is oppertunistic sampling?

Answer 13

decides sample based on prior knowledge of the habitat

Question 14

what is one advantagr and one disadvantage of oppertunistic sampling?

Answer 14

easier and quicker than random

may be biased

Question 15

what is stratified sampling?

Answer 15

dividing habitat into areas that appear different and sampling each area

Question 16

what is one advantagr and one disadvantage of satrtified sampling?

Answer 16

ensures all different areas are sampled

may lead to over representation of

Question 17

what is systematic sampling?

Answer 17

samples are taken at fixed intervals across habitat (line/belt transects)

Question 18

what is one advantage and one disadantage of systematic sampling?

Answer 18

useful when habitat shows gradient

some species may be missed

Question 19

Sweep netting is a technique used to catch invertebretes. How is thhis done?

Answer 19

sweep net through vegitation
small animals will be caught in net
empty them onto white sheet to identify them.

Question 20

what is a pitfall trap?

Answer 20

small container buired in soil containing little water or scrunched paper to stop animals crawling out again

Question 21

what is a light trap?

Answer 21

uv light attracts insects who eentually fall into the alcohol at bottom

Question 22

what does simpsons index of diversity measure?

Answer 22

diversity of a habitat takin into accountspecies richness and evenness

Question 23

What is the formula for species index of diversity?

Answer 23

d= (sum (n/N)^2)

Question 24

What 4 things affect biodiversity?

Answer 24

human population growth
agriculture
cllimate change
extinction

Question 25

how does human popluation growth affect biodiversity?

Answer 25

we alter ecosystems to get fppd
we destroy habitats
we pollute atmosphere

Question 26

how does agriculture affect biodiversity?

Answer 26

monoculture (crop consisting of one strain of species) has very limited genetic diversity

Question 27

what are the 3 sets of reasons to maintain biodiversity?

Answer 27

ecological
economic
aesthetics

Question 28

What is the ecological reason to maintain biodiversity? 3

Answer 28

1) individuals are interdependent upon each other for survival in food chains
2) keystone species are individuals that have a disproportionate
impact on a habitat and its biodiversity
3) if biodiversity declines, genetic diversity declines,

Question 29

What are 4 of the economic reasons to maintain biodiversity.

Answer 29

reducing soil erosion/depletion
 reducing the mineral depletion that occurs in monoculture
 sustainability – using natural resources without their loss
 avoiding the loss of potentially economically valuable species
 avoiding the rapid spread of disease seen in monoculture
 promoting tourism to an area
 giving greater potential for the manufacture of products
 giving greater genetic diversity that could be useful in genetic
engineering

Question 30

What is the aesthetic reason to maintain biodiversity?

Answer 30

 providing beautiful environment for people to live in

 it would be wrong to destroy natural beauty

Question 31

What is conservation in situ?

Answer 31

arrying out active management to maintain the biodiversity in the natural environment

Question 32

What is conservation ex situ?

Answer 32

conservation outside the normall habitat of the species

Question 33

state 2 advantages of conservation in situ.

Answer 33

conserved in natural environment
permanenly protects biodiversity
improve and restore ecological integrity

Question 34

state 2 disadvantages of conversation in situ.

Answer 34

habitat may be fragmented so areas not large enough to ensure survival.
may have already lost most of its genetic diversity
may attract poachers/tourists causing disturbance

Question 35

state 2 advantages of conservation ex situ.

Answer 35

protected from predator and poaching
health monitored and medical assistance
populations can be divided so if disasted strikes one, the other will survive.
selective breeding
bred to increase numbers of endangered species
attractions to raise funds for further conservation
education

Question 36

give 2 disadvantages of onservation ex situ

Answer 36

limited genetic diversity
exposed to many diseases
living outsie natural habitat
dont behave as normal
difficult to achieve correct environmental conditions
expensive to achieve correct environmental conditions
have to survive reintroduction to wild
difficulties with acceptance from preexisting wild members of species

Question 37

Give 2 advantages of botanic gardens.

Answer 37

seeds are produced in large numbers so can be collected without disturbing population
protected surroundings
dont occupy much space to store
stored/germinated in protected surroundings
can be replanted in wild

Question 38

Give 2 disadvantages of botanic gardens

Answer 38

funding is difficult
collectin wild seeds causes some disturbance
samples wont have representive genetic diversity
stored for too long wont be viable
asexual breeding will be genetically identical so low genetic diversity
research on small sample maybe not valid for whole species

Question 39

What does CITES do?

Answer 39

Regulate trade in selected species
Encourage trade does not endanger species
Permits enforced for trade of less endangered species
Allow trade for artificially propagated plants

Question 40

Explain the importance of sampling in measuring the biodiversity of a habitat. (2)

Answer 40

impossible / difficult , to count every individual ;
sample provides an estimate ;
sample representative (of whole area) ;

Question 41

Why do we need to measure both richness and evenness to assess biodiversity?

Answer 41

idea that both (richness and evenness) are needed to
reveal dominance ;
idea that high biodiversity associated with high species
richness and high species evenness ;

Question 42

Explain why it is sometimes necessary to conserve a plant species (3)

Answer 42

(natural) habitat / ecosystem , lost due to / destroyed
by / under threat from , climate change /
(named) human activity ;
number / population , (in natural habitat) is very low ;
idea that in the wild, (sexual) reproduction is difficult (if
numbers are low) ; ora
(breeding ex situ can) maintain , the gene pool /
genetic / allelic , diversity; ora
idea that allows protection from , grazers / herbivores
/ plant collectors / competing species ; ora
idea of protection from ,
pathogen / parasites / disease ; ora

Question 43

Give 3 advantages of conserving plant species as seeds and not as adult plants.

Answer 43

can be collected with minimal damage to (wild) ,
population / habitat / ecosystem ;
take up little space / larger numbers can be stored ;
can store great(er) , genetic / allelic , diversity
low(er) maintenance / manpower costs /
easy / cheaper, to transport /
idea of remaining viable for long periods
less , susceptible / vulnerable , to, disease / pests /
environmental change ;
Idea that prevents fertilisation by undesired pollen ;

Question 44

Outline the implications for a habitat if the Simpson’s Index of Diversity is low. (2)

Answer 44

(habitat) dominated by, one / few / AW, species ;
change in one species , likely to affect whole
habitat / AW ;
community / ecosystem / habitat / area , is
unstable / not able to withstand change /
easily damaged ;