Module 4- biodiversity

Question 1

Definition of biodiversity

Answer 1

the complexity of a biological community

Question 2

Definition of a habitat

Answer 2

area where an organism lives

Question 3

Definition of species richness

Answer 3

number of species in a habitat or community

Question 4

How can species richness be measured?

Answer 4

by counting the number of different species in a habitat

Question 5

Give 2 reasons how human population growth affects biodiversity?

Answer 5

-to create enough space for housing, farming and industry to support the increasing population, humans are severely disrupting the ecology of many areas through deforestation
-increase of pollution and waste production which put burden on fragile ecosystems

Question 6

How has climate change affected biodiversity?

Answer 6

-changes in global weather pattern, sea levels and temperatures can lead to habitat loss causing animals to migrate
-in some cases species may be directly destroyed, decreasing the gene pool available for natural selection and evolution
-the speed of climate change can mean that species can’t adapt quick enough to new conditions leading to extinction

Question 7

How has deforestation affected biodiversity?

Answer 7

-destroys habitats so causes species to migrate or die

Question 8

How has agriculture affected biodiversity?

Answer 8

farmers will only grow a few species based on characteristics that give a high yield which reduces the biodiversity of an area

Question 9

How is biodiversity measured?

Answer 9

using the simpsons index of diversity
-greater the value=higher biodiveristy
-uses species richness and species evenness

Question 10

What is the relationship between genetic diversity and number of alleles at a gene locus?

Answer 10

the greater the genetic diversity the greater the number of different alleles at a given gene locus there are coding for different variations of a characteristic

Question 11

What is the equation for genetic diveristy?

Answer 11

genetic diveristy=number of polymorphic gene loci / total number of loci x 100

Question 12

What ensures the basic structure of individuals within a species remains consistent?

Answer 12

-most genes are monomorphic (a single allele exists for this gene)

Question 13

Define locus of a gene

Answer 13

position of a gene on a chromosome

Question 14

What creates a new allele for a gene

Answer 14

a mutation

Question 15

What are the 3 broad reasons for maintaining biodiveristy?

Answer 15

-aesthetic
-environmental
-economic

Question 16

What are aesthetic reasons for maintaining biodiversity?

Answer 16

-presence of a variety of plants and animals enriches our lives and improves our mental health by relieving stress
-provides inspo for poets, musicians and writers

Question 17

What are economic reasons for maintaining biodiversity?

Answer 17

-soil erosion and desertification may occur as a result of deforestation which will reduce a countries ability to grow crops and therefore profit off of this land
-large scale habitat destruction means that species with potential economic importance may become extinct
-highly biodiverse areas can promote tourism bringing economic advantages
-maintains genetic resources to call on in the development of new medicines

Question 18

What are ecological reasons for maintaining biodiversity?

Answer 18

-all organisms are interdependent on one another for survival so the removal of one species may have a significant effect on the others

Question 19

What is in situ conservation?

Answer 19

-takes place inside an organisms natural habitat where the environment is preserved and carefully managed

Question 20

What are the benefits of in situ conservation?

Answer 20

-maintains genetic diversity and evolutionary adaptations
-preserves interdependent relationships present in a habitat therefore interlinked species may also be preserved
-is generally cheaper than ex situ.

Question 21

What are 2 examples of in situ conservation?

Answer 21

-wildlife reserves
-marine conservation zones

Question 22

What is involved in wildlife reserves?

Answer 22

-once an area has been designated, active management is required e.g controlled grazing, restricting human access, halting succession

Question 23

What is involved in marine conservation zones?

Answer 23

-purpose is not to prevent the fishermen from visiting the entire area but to create areas of refuge where populations can build up
-large areas of sea are required

Question 24

What is ex situ conservation?

Answer 24

-involves the removal of organisms from their natural habitat
-usually used in addition to in situ measures

Question 25

What are 3 examples of ex situ conservation?

Answer 25

botanic gardens, seed banks, captive breeding programmes

Question 26

What is involved in botanic gardens?

Answer 26

-plants species are actively managed to provide them with the best resources to grow

Question 27

What is involved in seed banks?

Answer 27

-seeds are carefully stored so that new plants may be grown in the future -are dried and stored at -20deg c to maintain their viability by slowing down the rate at which they loose their ability to germinate -however it doesn't work for all plants as some die when dried or frozen

Question 28

What is involved in captive breeding programmes?

Answer 28

-produce offspring of species in a human controlled environment -are often run and managed by zoos and aquatic centres -aims to create a stable, healthy population of species before reintroducing it back into the wild -provide species with an abundance of food, absence of predators and veterinary treatment -problems related to inbreeding can occur -to overcome this an international catalogue of genealogical data on individuals is maintained to arrange mating so genetic diversity is maximised

Question 29

Name 3 conservation agreements

Answer 29

CITES CBD Countryside stewardship scheme

Question 30

What is CITES?

Answer 30

international agreement between 180 governments that ensures licenses are required to import or export specific species in order to protect them from extinction

Question 31

What is CBD?

Answer 31

-between 150 governments -action plans to conserve biodiversity and promote sustainable use of natural resources -takes steps to stabilise greenhouse gas concentrations -prevents transformation of fertile land to desert

Question 32

What is the countryside stewardship scheme?

Answer 32

-uk scheme that provides grants for farmers, foresters, woodland owners and land managers to make improvements to the environment e.g flood risk management, conservation and restoration of wildlife habitats, reduction of water pollution -operated 1991-2014

Question 33

Define sampling

Answer 33

taking measurements of a limited number of individual organisms present in a particular area -used to estimate number of organisms in an area without counting them all

Question 34

What is random sampling?

Answer 34

-selecting individuals by chance -each individual in a population has an equal likelihood of selection -you have no involvement in deciding which organisms to investigate which ensures minimal selection bias

Question 35

What is stratified sampling?

Answer 35

-some populations can be divided into a number of strata (sub groups) based on a particular characteristic -a random sample is then taken from each of these strata proportional to its size -can produce more accurate and meaningful results if knowledge of what constitutes to a certain characteristic is acquired

Question 36

What is systematic sampling?

Answer 36

-different areas within an overall habitat are identified which are then sampled separately -often carried out using a line or a belt transect -is easy to implement -can lead to bias if sampling intervals coincides with underlying patterns within the sampling population

Question 37

What is opportunistic sampling?

Answer 37

-weakest form of sampling as may not be representative of the population -uses organisms that are conveniently available

Question 38

How do you use a pooter?

Answer 38

-use to catch small insects by sucking on mouth piece -insects are drawn into a holding chamber via the inlet tube -a filter before the mouth piece prevents them from being sucked into the mouth

Question 39

Why do you use a sweep net?

Answer 39

used to catch insects in areas of long grass

Question 40

How do you use a pitfall trap?

Answer 40

-used to catch small, crawling insects -a hole is dug into the ground which they fall into -has to be deep enough so they cant crawl out and have a roof propped above it so it doesn't fill with rain water -often left overnight so nocturnal species can also be sampled

Question 41

What is a point quadrat and how do you use it?

Answer 41

-frame containing a horizontal bar that at set intervals long pins are pushed through the bar to reach into the ground -each species of plant the pins touch is recorded

Question 42

What is a frame quadrat and when is it used?

Answer 42

-square frame divided into a grid of equal sections -the types and numbers of species within each section of the quadrat is recorded -where individual members of a species are hard to count e.g grass count the number of squares the species is present within out of 100 to get the frequency -if species are large and easy to count, count the number of them within the quadrat -calculate percentage cover for speed where a rough estimate is taken of the area in which a species covers

Question 43

How do you carry out the capture-mark-release-recapture

Answer 43

-capture as many species within an area as possible -mark these organisms and then release them back into the community -time is allowed so the organisms can redistribute themselves into the community before another sample is gathered -they then compare the number of marked individuals against unmarked individuals to estimate the population size