Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

A Level Biology > Chapter 11 - Biodiversity > Flashcards

Chapter 11 - Biodiversity Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

what is the benefit of biodiversity?

A

a key idea is that the higher the BD of an area. the more resilient that area is to environmental change e.g. climate change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

BD is built out of intertwined features:?

A

Ecosystem diversity, species diversity, genetic diversity. the more intertwining, the denser and more resilient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

why is BD imp?

A
  • it’s vital for the survival of organisms on Earth
  • essential in maintaining a balanced ecosystem for all organisms
  • we rely on a balanced ecosystem as they provide us w the food, O2 and other materials we need to survive.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

habitat (ecosystem) diversity definition?

A

Refers to the number of different habitats found within an area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

species diversity is made up of?

A

species richness + species evenness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

species richness definition?

A

the no. of diff species living in a particular area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

species evenness definition?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

genetic diversity definition ?

A

refers to the variety of genes that make up a species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

habitat diversity e.g.?

A
  • UK is home to a large no. of habitat types, including meadow, woodland, streams, sand dunes. It has a large habitat diversity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

species richness e.g.?

A

there are approx 10 million species in the Amazon rain forest - high species richness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

species evenness e.g.?

A

25 dogs, 25 frogs, 25 cats, 25 monkeys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

genetic diversity e.g.?

A
  • diff breeds within a species
  • GBD can lead to diff characteristics being exhibited - some genes are the same for all breeds of dog but some of the genes have many alleles - code for variation in the characteristics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

habitat definition?

A

the place where an organism lives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

species definition?

A

a group of organisms w similar morphology and physiology that can interbreed to produce fertile offspring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

community definition?

A

all organisms of all species, living in the same habitat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

ecosystem definition?

A

a relatively self-contained system inclu all organisms and aspects of their envir, and the way they interact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

biodiversity definition?

A

the range of habitats, communities and species present in an area, and the genetic variation within species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

niche definition?

A

the role of an organism in its community in terms of the habitat it occupies, its interaction with other organisms and its effect on the environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

population definition?

A

the no. of organisms of any one species living in the same habitat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is sampling & why is it needed?

A
  • in order to collect data from a habitat, it’s usually impossible to look at every single organism.
    This means that sampling is needed -taking a rep sample of the organisms and collecting data just from them.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is sampling used for?

A

to collect ecological data from an area, often to measure its BD, in order to make decisions about e.g. conservation, or the impact of developing that area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

there are 2 main methods of sampling that can be used, depending on the distribution of organisms in the habitat:

A
  • random sampling - if organisms are evenly distributed, each individual in the pop has an equal likelihood of selection
  • non random - if there is a patter in the distribution of organisms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

3 types of non random sampling r ?

A
  • opportunistic
  • stratified
  • systematic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

opportunistic sampling definition?

A

sampling organisms that are most conveniently available - not a strong tech bc v prone to bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

stratified sampling ?

A

/ing the habitat into sections- strata- then sampling randomly within these strata

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

systematic sampling ?

A

placing a tape measure along a transect, then sampling at fixed intervals. This can be a line transect or a belt transect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is a Quadrat?

A

a piece of equipment used to sample sessile organisms - organisms that don’t move - plants, lichens, barnacles, ect…

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

2 types of Quadrat are?

A
  • frame

- point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

frame quadrat?

A
  • each sq represents 4% of the area of the quadrat - helpful for % cover estimates, but not as acc as point quadrat.
  • how 2 choose correct size: neess to be big enough to include a majority of the diff species present each time it is placed (abt 75% maybe??)
  • usin it to estimate % cover is a rough estimate and quite subjective
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

point quadrat?

A
  • the % cover is much more accurately estimated
  • the higher the 5 cover, the more likely a pin will touch a leaf as it is lowered
  • the no. of touches is proportional to % cover
  • if one leaf is found over another, the pin may touch both, both are counted
  • this method is less susceptible to error than some other estimates of abundance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what data is collected at random coordinates and what at points along a transect?

A

it depends. If organisms are sessile, like plants, then a quadrat is used - either a frame or a point
3 values can b measured

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

which 3 values can be measured?

A

1) species frequency- tick or cross - presence or absence of species
2) species density - the no. of individuals of each species in a quadrat
3) % cover- the % each species covers of the quadrat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

if the species are motile then….

A

diff sampling techniques are used e.g. long-worth trap, kick sampling, sweep net, trap for night-flying moths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

abiotic factors?

A
  • also imp to collect info abt the non-living components of the envir
  • these r factors like wind speed, soil temp and light intensity - factors which might affect the distribution of the living organisms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

abiotic factor: air,/soil/water temp and how measured?

A

thermometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

AF: wind speed - how is measured?

A

Anemometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

AF: soil moisture content - how is measured?

A

measure mass, dry in oven, then measure mass again

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

AF: soil hummus content and how is measured?

A

measure mass, burn off humus w Bunsen, measure mass again

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

AF: soil, water pH - how is measured?

A

pH meter or indicator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

AF: air humidity- how is measured?

A

hygrometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

random sampling e.g.?

A
  • e.g. to take a random sample at a grass verge

- used to place a frame quadrat?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

stratified sampling e.g.?

A

the pop may be split into males and females. A random sample is then taken from each of its strata proportional to its size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

systematic sampling e.g.?

A

used to study how plant species change as you move inward from the sea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Frame quadrat description?

A

this consists of a square frame / into a grid of equal sections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

how can a frame quadrat be used?

A
  • the type and no. of species within each section r recorded
  • use random sampling, can be placed along a transect (line or belt)
  • density/ freq/ % cover
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

point quadrat description?

A
  • consists of a frame containing a horizontal bar. At set intervals along the bar, long pins can be pushed into the bar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

how can a point quadrat b used?

A
  • each species of plant the species touches is recorded

- % cover is more accurately estimated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

longworth trap?

A
  • used to catch small mammals

- traps checked at least once a day, animals marked then released

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

light trap?

A
  • used for capturing night flying moths

- they r attracted to the light and fall into the box below

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

sweep net?

A
  • captures insects in vegetation

- each type of vegetation requires a diff standard method of sweeping the net

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

kick sampling?

A

involves one person disturbing the stream bed w their feet so that organisms are swept down into a net held by another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

the Lincoln index equation?

A
  • N = n1 x n2 / m
    N = total pop size of animal of interest in study site
    n1 = no. of animals captured on the first day
    n2 = number of animals recaptured on the 2nd day
    m = no. of marked animals in the sample recaptured on the 2nd day
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

the capture/ mark/ recapture technique ?

A

(also called the Lincoln Index) can be used to estimate the size of a population of motile organisms like small mammals, or invertebrates like woodlice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

explain how the capture/ mark/ recapture technique (Lincoln index) works?

A

take a group of organisms from the pop, mark them, then release them back into the pop. Capture a 2nd group and check how many had the mark. Do 3x use formula to calc pop size and calc an average

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

what would you do to make the Lincoln index as accurate as possible?

A
  • repeat many times
  • use large no.s when capturing
  • if pop is spread out, capture from a range of diff areas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

what would the considerations need to b when marking the organisms ?

A
  • pain, temp/ long term?, uncomfortable, more visible to predators?, does it affect their ability to move, hunt, ect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

what would the consequences of an overestimated/ underestimated pop be?

A

overestimate - might think it’s ok to do construction that affects the animal habitat when in reality it would be damaging for the ecosystem to lose it
underestimate - might remove habitats that r needed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

does sampling produce valid data?

A
  • yes and no
  • sampling can never be entirely rep of all the organisms in a habitat, bc not all organisms r measured
  • data can b skewed by: sampling bias - which can be by accident or deliberate , chance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

how to prevent data being skewed?

A
  • collect an appropriate set of data - a large enough sample size
  • use appropriate equip - e.g. correct size frame quadrat
  • standardise techniques so samples are take in exactly the same way each time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Simpson’s index of BD?

A
  • this is a quan measure of the BD of a habitat, and can be used to compare the BD of 2 habitats
  • takes into account both species richness and species evenness - a measure of the relative abundance of each species
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

to calculate Simpson’s index what do u need?

A

species density or % cover data from 2 or more habitats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

genetic variation?

A

within any pop, individuals have diff sets of alleles, and therefore show genetic variation. this is the main reason indivs are diff from one another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

high level of genetic BD is when?

A

there is a wide range of diff alleles within a pop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

low level of genetic BD is when?

A

the range of alleles is narrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

gene pool is ?

A

the range of alleles within a pop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

what is a robust population?

A
  • a pop w a high level of GBD is a ‘robust’ pop as they are much better able to respond and adapt to changes in their envir like climate change or disease. A pop like this is described as having a deep gene pool.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

a pop w a low GBD?

A
  • is much less able to adapt to change like this, and s thfr much more likely to become extinct. A pop like that is described as having a shallow gene pool.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What is the main goals of conservation?

A

is to try and maintain and even increase GBD within a species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

the chance of sampling bias can be reduced by using?

A

random sampling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Why does a larger sample size mean a more reliable result?

A
  • chance can never b completely removed from the process, but its effect can be minimised by using a large sample size
  • the ⬆ the no. of individuals studied, the ⬇ the prob that chance will influence the result
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

what is a species?

A

a group of organisms that are capable of interbreeding to produce fertile offspring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

within an ecosystem?

A

there will be many diff species co-existing - they form an area’s BD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

what is BD?

A

A measure of the variety of life in area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

e.g.s of ecosystems w ag high species diversity?

A

coral reefs and rainforests

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

what is ecosystem diversity?

A

a measure of the no. of diff habitats in an ecosystem/ larger areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

species richness is diff?

A

bc it’s diff to ensure that all of the species present are recorded (hide, nocturnal, small, inactive, ect..)
on it’s own, is an inefficient measure of BD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What is species evenness useful to see?

A

if there is a dominant species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

what is the Simpson’s Index of BD?

A

A quan measure of BD in a habitat that gives a comparable score

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

higher d value =?

A

higher BD

80
Q

Species w a greater proportion of polymorphic genes tend to have a ?

A

greater GD bc more versions and thfr more diverse choices of characteristics

81
Q

what is a polymorphic gene?

A

a gene that exists in 3 or more diff possible versions/ alleles

82
Q

A locus is?

A

(plural loci) the position of a gene on a chromosome

83
Q

⭐ can’t have?

A
  1. something of an organism ➡ round
84
Q

factors affecting BD: climate change?

A
  • as climate gets warmer, organisms can either adapt to the new conditions, migrate, die
  • many organisms incapable of migrating quickly e.g. some insects that live locally
  • domesticated plants & animals have relatively low G.D so may be less able to adapt quickly to changing conditions
85
Q

importance of ecosystems?

A
  • benefit our economy (creates jobs), our health (calming and provide medicine)
86
Q

ecosystem services?

A
  • provisioning services
  • Regulatin services
  • Supporting services
  • Cultural services
87
Q

provisioning services?

A

(provides us w materials) e.g. food, wood, fuel, med e.g. Aspirin

88
Q

regulating services?

A

e.g. forests help to purify air by taking in CO2, producing O2, bees help pollinate, trees and plants are a store of water

89
Q

supporting services?

A

e.g. nutrient cycling, death and decay of certain plants helps remake soil -> growth of new plants

90
Q

cultural services?

A

e.g. Tourism -> money, aesthetic -> calming, Religious imp

91
Q

keystone species?

A

is one that gas a disproportionate effect on its envir relative to its abundance. Removal may greatly reduce the ability of an ecosystem to function

92
Q

ethical arguments for conservation?

A
  • if we damage ecosystems now, we may prevent future generations from enjoying them
  • there may be uses of some species that have not been discovered yet and so we lose the chance if we drive them to extinction now
  • the organisms we are affecting often have no direct impact on our lives, so is it right for us to destroy their habitats? e.g. rabbits
93
Q

CITES?

A
  • protects endangered animals and plants by regulating the trade of products that come from them
  • 180 nations have signed up to CITES
  • altho it’s not a legally binding agreement, trade sanctions are used against those who breach the contract
94
Q

+s and -s of CITES?

A

+ Has experienced success in inc BD

  • Only regulates trade agreements - it does not legislate for other measures such as the protection of breeding grounds
  • some countries have not signed up to CITES e.g. Haiti
  • no legal obligation to abide by this convention
95
Q

CBD?

A
  • Requires countries to develop national strategies for sustainable develop thereby maintaining BD
96
Q

CCS?

A
  • local scale
  • encouraged local farmers to ptotect and enhance the english countryside
  • spec aims: - to sustain the beauty and diversity of the landscape, improving the oppor for ppl to enjoy the countryside, improving, extending & creating wildlife habitats, restoring neglected land and conserving archaeological &historic features
  • replaced by ESS
97
Q

how can genetic diveristy be increased?

A

by increasing the number of different alleles in a population. This can be achieved by: mutation or intererbreeding between pops.

98
Q

Mutation?

A

Mutation of DNA, producing new alleles.

99
Q

Interbreeding ?

A

Interbreeding between populations (migration) resulting in gene flow.

100
Q

How can GBD be decreased?

A

by decreasing the number of different alleles in a population. This can be achieved in a number of different ways:

101
Q

how can genetic diversity be decreased?

A
  • Selective breeding / artificial selection
  • Captive breeding programmes
  • Domesticated breeds that have become rare
  • Artificial cloning
  • Natural selection
  • Genetic bottleneck
  • The founder effect
  • Genetic drift
102
Q

Selective breeding / artificial selection?

A

for example the breeding of pedigree animals like dogs.

103
Q

Captive breeding programmes?

A

eg in zoos, when the wild population is small or even extinct.

104
Q

Domesticated breeds that have become rare?

A

for example rare breed pigs like the Gloucester Old Spot.

105
Q

Artificial cloning?

A

for example using cuttings to produce many copies of a perennial plant, like a fruit tree.

106
Q

Natural selection?

A

alleles that cause disadvantageous traits are lost from populations over time.

107
Q

Genetic bottleneck?

A

when a population has been reduced to a very few individuals, then recovered. The new population has a very shallow gene pool, with low genetic diversity.

108
Q

The founder effect?

A

when a new population is ‘founded’ by a very small number of individuals from an original population. The new population has a very shallow gene pool, with low genetic diversity.- due to a natural disaster

109
Q

Genetic drift?

A

in small, isolated populations, the random passing on of alleles to the next generations can cause alleles to become extinct.
2 types: the Bottleneck effect, Founder Effect

110
Q

the Genetic Diversity within a population can be calculated if?

A

if we know how many of a populations’ genes have more than one allele. Genes with more than one allele are polymorphic (poly = many; morph = form)

111
Q

most genes are?

A

monomorphic - they just have one allele, so the higher the proportion of polymorphic genes, the higher the genetic diversity of a population.

112
Q

what is a gene locus?

A

A gene is found at a particular location on a chromosome.

113
Q

so gene loci can be either?

A

can be polymorphic, or monomorphic.

114
Q

how can genetic BD be quantified?

A

by calculating the proportion of polymorphic gene loci in a population

115
Q

proportion of polymphoric genes equation?

A

Proportion of polymorphic gene loci =

No. of polymorphic gene loci/ Total no. of gene loci

116
Q

what are the 3 main ways humans are influencing BD?

A

Deforestation, Climate Change, Agriculture

117
Q

What are the 3 main reasons for maintaining biodiversity?

A

Aesthetic reasons, ecological reasons, economic reasons

118
Q

main reasons for maintaing BD - aesthetic?

A

A diverse natural environment is inspiring, beautiful and has positive influences on both physical and mental health.

119
Q

main reasons for maintaining BD - ecological?

A

Maintaining genetic resources within ecosystems by protecting keystone species and preserving the interdependence of organisms.

120
Q

main reasons for maintaing BD - economic?

A

Biodiverse areas often provide economically useful resources, both now and potentially in the future.

121
Q

What are the main methods for maintaining biodiversity?

A

conservation

122
Q

2 main types of conservation?

A

In Situ, Ex situ

123
Q

In situ conservation?

A
  • within the natural habitat. For example wildlife reserves and marine conservation areas.
124
Q

Ex situ conservation?

A

outside the natural habitat. For example botanic gardens, seed banks, captive breeding programmes in zoos.

125
Q

What are some of the agreements and legislation in place for protecting and maintaining biodiversity?

A
  • CITES
  • Countryside Stewardship scheme
  • the Rio Convention on Biological Diversity (CBD)
126
Q

What are the factors that increase BD?

A
  • Mutation

- Interbreeding

127
Q

what are the factors that decrease BD?

A
  • Selective Breeding
  • Captive breeding
  • Domesticated breeds
  • Artificial cloning
  • Natural selection
  • Genetic Bottleneck
  • The founder effect
  • Genetic Drift
128
Q

pros (+s of sampling)?

A
  • random sampling reduces sampling bias
  • large sample size reduces chance factors
  • unrealistic to count every organism as pop size may be too large
129
Q

cons of sampling?

A
  • sampling bias ➡ data is less valid
  • chance factors
  • opportunity sampling ➡ bias
130
Q

which areas have the most BD and which have the least?

A
  • tropical, moist = most
  • very cold like Arctic or very dry like desert have least
  • generally closer to equator, have more
131
Q

measuring BD plays an important role in?

A
  • conservation. It informs scientists of species present & thus provides a baseline for the level of BD in an area. From this info, the effect of any changes to an envir can be measured e.g. climate change, human activity, disease
132
Q

why can an area differ in species diversity even if it has the same no. of species?

A

diff eveness

133
Q

greater DB within a species allows for?

A

better adaptation to a changing envir, and is more likely to result in individuals who are resistent to disease.

134
Q

alongside estimating the no. of species in an area, sampling can also be used to?

A

measure a paticular characteristic of an organism.

135
Q

what to remember when sampling animals?

A

all living organisms must be handled carefully and for as short a time period as possible. As soon as any sample animals have been identified, counted and measured if required, they must be released back into the habitat at the point they were collected

136
Q

what is a pooter used for?

A
  • sampling animals
  • used to catch small insects. By sucking on a mouthpiece, insects are drawn into the holding chamber via the inlet tube. A filter before the inlet prevents them being sucked into the mouth
137
Q

what is a pitfall trap used for?

A
  • sampling animals
  • used to catch small, crawling invertebrates such as beetles, spiders, slugs. A hole is dug in the ground which insects fall into - must be deep enough that they can’t crawl out and covered with a roof structure propper above so rainwater doesn’t fill trap.
  • usually left overnight so nocturnal species also sampled
138
Q

what is tree beating used for?

A
  • sampling animals
  • used to take samples of the invertebrates living in a tree or bush. A large white cloth is stretched out under tree and tree is shaken or beaten to dislodge invertebrates.
  • animals will fall onto the sheet where they can be collected and studied
139
Q

how are plants normally sampled?

A

using a quadrat, which can also b used to pinpoint an area in which the sample of plants should be collected & to sample slow moving animals e.g. sea anemones

140
Q

why is a frame quadrat used?

A

to sample the pop of plants living in a habitat

141
Q

how can frame quadrats be used to sample the pop of plants living in a habitat?

A

3 main ways:

  • density - if indiv large plants can be seen clearly, count the no. of them in 1m x 1m square quadrat- will give density per square m. - ABSOLUTE measure not estimate
  • freq - used where individual members of a species are hard to count. Use the small grids within a quadrat, count the no. of squares a paticular species is present in.
  • % cover - lots of data can be collected quickly. useful when a paticular species is abundant or diff to count. It is an estimate by eye of the area within a quadrat that a paticular plant species covers.
142
Q

how is animal pop size calculated?

A
  • as animals are constantly moving & may be hidden, can be diff to accurately determine pop size.
  • capture-mark-release-recapture tech used
  • this involves capturing as many indivds of a species an area as poss, organisms marked, released back into community.
  • time is allowed for organisms to redistribute themselves throughout the habitat before another sample of animals is collected
  • by comparing no. of marked vs not marked in 2nd sample, can estimate pop size
  • the greater the no. of marked individs, the smaller the pop
143
Q

why is it advantageous that many abiotic factors can be meassured quickly and acc using a range of sensors?

A
  • rapid changes can b detected
  • human error in taking a reading is ⬇
  • a high degree of precision can often be acheived
  • Data can be stored and tracked on a computer
144
Q

Simpson’s Index of Diversity always results in?

A

a value between 0 and 1, where 0 represents no diversity and a value of 1 represents infinite D.

145
Q

systematic sampling?

A
  • diff areas within an overall habitat are identified, which are then sampled sep.
  • E.g. might be used to study how plant species change as you move inland from the sea.
  • Often carried out using line or belt transect
146
Q

line transect?

A

involves marking a line across the ground between 2 poles and taking samples at specified points, this can include describing all of the organisms which touch the line or distances of samples from the line.

147
Q

belt transect?

A

provides more info: 2 parallel lines are marked and samples are taken of the area between the 2 lines

148
Q

why is it important to preserve habitats of low BD as well as habitats w high BD?

A
  • altho some habitats w a low BD are unable to support a large species diversity, those organisms that are present in the habitat can be highly adapted to the extreme envir of the habitat & may not survive elsewhere. Conserve rare species that may be too specialised to survive elsewhere
149
Q

Why are species w a greater GBD more likely to survive?

A
  • likely to be able to adapt to changes in envir
  • less likely to become extinct
  • as are likely to be some organisms in the pop that carry an advantageous allele which enables the to survive in the altered condition.
150
Q

factors affecting GBD - natural selection?

A
  • as a result, species will evolve to contain primarily the alleles which code for advan characs
  • over time alleles coding for less advan characs will be lost form a pop, or only remain in a few indivs
151
Q

factors affecting GBD - genetic bottlenecks?

A

where few indivs in a pop survive an event or change (e.g. disease) thus reducing the ‘gene pool. Only the alleles of the surviving members of the pop are available to eb passed on to offspring

152
Q

factors affecting GBD - genetic drift?

A

due to the random nature of alleles being passed on from parents to offspring, the freq of occurrence of an allele will vary. In some cases, the existence, of a particular allele can disappear from a pop altogether.
- is more pronounced in pops w low GBD

153
Q

why is maintaining BD essential for preserving a balanced ecosystem for all organisms?

A

as species are interconnected within an ecosystem, the removal of one organism can have a profound effect on others.

154
Q

why are humans having an impact on BD?

A
  • To create enough space for housing, industry, and farming to support the inc pop, humans are seevrly disrupting the ecology of many areas
155
Q

the main problems occurring as a result of humans?

A
  • deforestation
  • agriculture
  • climate change
156
Q

deforestation is?

A

the permanent removal of large areas of forest to provide wood for building and fuel and to create space for roads, building and agriculture,.

157
Q

agriculture is?

A

an increasing amount of land has had to be farmed in order to feed teh growing pop. this has resulted in large amounts of land being cleared and in many cases planted w a single crop (monoculture)

158
Q

climate change?

A

CO2 and other pollutants into the atmosphere from the burning of fossil fuels is ⬆ global temps

159
Q

how does deforestation impact BD?

A
  • directly ⬇ no. of trees in an area
  • if only a spec type of tree is felled, species diversity is ⬇
  • destroys habitat and food source for for animals, so less animal species
  • animals forced to migrate
160
Q

how does agriculture affect BD?

A
  • Farmers use techs to max food production:
  • deforestation - more space for crops/ rearing animals
  • removal of hedgerows - to enable them to use large machines to help plant crops, and it frees up land for growing crops. reduces no. of plant species and destroys habitat of animals e.g. blackbird
  • chemicals e.g. pesticide and herbicides
  • monoculture - only 1 species of plant is present so ⬇ BD, also few animal species will be supported by only 1 species so low overall BD levels
161
Q

what are pesticides used for?

A

kill pests that would eat the crops or live on the animals. this ⬇ species diversity directly as it destroys the pest species and indirectly by destroying food source of other organisms.

162
Q

what are herbicides used for?

A

kill weeds. this reduces plant diversity and animal diversity by the removal of an imp food source

163
Q

IPCC report on climate change key findings?

A
  • the warming trend over the last 50 years is nearly 2x that of the previous 100 yrs
  • the average amount of water vapour in the atmosphere has ⬆ since 1980s over land and ocean, is consistent with the extra water vapour warmer air can hold
164
Q

IPCC report on climate change key findings?

A
  • the warming trend over the last 50 years is nearly 2x that of the previous 100 yrs
  • the average amount of water vapour in the atmosphere has ⬆ since 1980s over land and ocean, is consistent with the extra water vapour warmer air can hold
  • since 1961, the average temp of the global ocean down to the depths of 3km has inc
  • global average sea level rose by an average of 1.8mm per year 1961-2003
  • average Arctic temps have ⬆ at almost 2x the global average rate in the past 100 years
  • mountain glaciers and snow cover have declined on average in both hemispheres.
  • long term upward trends in the amount of precipitation have been observed over many regions 1990-2005
165
Q

effect of global warming on BD - ice caps?

A

the melting of the polar ice caps could lead to the extinction of the few plant and animal species living in these regions.

166
Q

effect of global warming on BD - sea levels rising?

A

rising sea levels from melting ice caps and the thermal expansion of oceans could flood low-lying land, ⬇ the available terrestrial habitats. saltwater would flow further up rivers ⬇ the habitats of freshwater plants and animals living in the river and surrounding areas

167
Q

effect of global warming on BD - higher temps?

A

higher temps and less rainfall would result in some plant species failing to survive, leading to xerophytes becoming more dominant. the loss of non drought-resistant species of plants would lead to the loss of some animal species dependent on them as a food source.

168
Q

effect of global warming on BD - insects>?

A

insect life cycles and pops will change as they adapt to climate change. insects are key pollinators of many plants so if the rage of an insect changes, it could affect the lives of the plant it leaves behind, causing extinction. And as insects carry many plant and animal pathogens, if tropical insects spread, this could lead to the spread of tropical diseases towards the poles

169
Q

If climate change is slow?

A

species may have time to adapt or migrate to new areas. this will lead to a loss of native species, but other species may move into the area - so BD may not necessarily be lost.

170
Q

aesthetic reasons for maintaining BD?

A
  • The presence of diff plants and animals in our envir enriches our lives.
  • The natural world provides inspo for ppl such as musicians and writers who in turn provide pleasure for others through books and music
  • studies have shown patients recover more rapidly from stress & injury when surrounded by plants
171
Q

economic reasons for maintaining BD? (productivity, erosion, industry)

A
  • levels of long term productivity are higher if BD is maintained
  • Soil erosion and desertification may occur as a result of deforestation. These reduce a country’s ability to grow crops and feed its ppl, which can lead to resource and economic dependence on other nations
  • Non sustainable removal of resources willl eventually lead to the collapse of the industry in an area.
  • Large scale habitta and BD losses mean that species w potential economic importance may become extinct b4 discovery.
172
Q

economic reasons for maintaining BD? (monoculture, protection against abiotic factors)

A
  • continuous monoculture results in soil depletion- a reduction in the diversity of soil nutrients which makes the ecosystem more fragile. The crops it can support will be weaker, inc vulnerability to opportunistic insects, plant competitors, microorganisms. Farmer will need to use more pesticides, herbicides and fertilisers
  • High BD provides protection against abiotic stresses and disease. When BD is not maintained, a change in conditions or dieases can destroy entire crops e.g. the Irish potato famine
173
Q

economic reasons for maintaining BD? (tourism, manufacture, cross breeding, extinction)

A
  • high BD areas can promote tourism
  • the greater the diversity in an ecosystem, the greater the potential for the manufacture of diff products in the future which may be beneficial to humans
  • plant varieties are needed for cross breeding, which can lead to better characs. The wild relatives of cultivated crops provide genetic material to aid the production of new varieties of crops + thru genetic engineering, scientists aim to use genes from wild p+a to make crop plants and animals more efficient thus ⬇ the land needed to feed more ppl
  • if these wild varieties are lost, the crop plants may become more vulnerable to extinction
174
Q

what is a keystoene species?

A

some species play a key role in maintaining the structure of an ecological community.

175
Q

human role in inc BD?

A

In Uk e.g. the natural habitat is created by human intervention in the management of land. E.g. farming, grazing, planting of hedges, meadows and forest management have changed the landscapes, habitats and ecology over 1000s of yrs.

176
Q

what is sustaibale development?

A

economic devlopment that meets the needs of ppl today without limiting the ability of future generations to meet their needs

177
Q

what does in situ conservation do?

A
  • takes place inside an organism’s natural habitat
  • maintains not only GD of species, but also the evol adaptations that enable a species to adapt continually to changing envir conditions
  • by allowing the endangered species to interact with other species, it also preserves interdependent relationships present in a habitat, therefore interlinked species may also be preserved.
  • generally cheaper than ex situ
178
Q

wildlife reserves?

A
  • once an areas has been designated as a wildlife reserve, active management is required. Active management techs may include:
  • controlled grazing
  • restricting human access
  • controlling poaching
  • feeding animals
  • reintro of species
  • culling or removing of invasive species
  • halting succession
179
Q

controlled grazing?

A

only allowing livestock to graze a particular area of land for a certain period of time to allow species time to recover, or keeping a controlled no. of animals in a habitat to maintain it.

180
Q

controlling poaching?

A

this includes creating defences to prevent access, issuing fines or more drastic steps such as the removal of rhino horns.

181
Q

feeding animals?

A

can help to ensure more organisms survive to a reproductive age.

182
Q

reintro of species?

A

adding species to areas that have become locally extinct, or whose no.s have decreased sig.

183
Q

culling or removal of invasive species ?

A

an invasive species is an organism that is not native to an area and has - effects on the economy, enir, heath. They compete w native species for resources

184
Q

halting succession?

A

succession is a natural process where early colonizing species are replaced over time until a stable mature pop is achieved.

185
Q

Marine conservation zones?

A

are less well established than terrestrial ones.

186
Q

Marine reserves?

A
  • are vital in preserving species- rich areas such as coral reefs, which are being devastated by non-sustainable fishing methods.
  • purpose is to create areas of refuge within which pops can build up and repopulate adjacent areas.
  • large areas of see are needed as target species often move large distances or breed in diff areas
187
Q

Ex situ conservation is?

A

involves the removal of organisms from their natural habitat. It is normally used in addition to in situ measures

188
Q

Botanic gardens?

A
  • plant species can be grown successfully here
  • the species are actively managed to provide them with the best resources to grow, e.g. provision of soil nutrients sufficient watering, removal/ prevention of pests
189
Q

Seed banks

A
  • e.g. of a gene bank
  • seeds are carefully stored so that new plants may be grown in future
  • they are dried and stored at temps of -20 degrees to maintain their viability, by slowing down the rate at which they lose their ability to germinate
190
Q

Captive Breeding Programmes?

A
  • produce offspring of species in a human controlled envir
  • often run and managed by zoos and aquatic centres
  • scientists working on CBPs aim to create a stable, healthy pop of a species and then gradually reintro the species back into its natural habitat
191
Q

why don’t seed banks work for all plants?

A

some seeds die when dried and frozen - the seeds of most tropical rainforest trees fall into this category.

192
Q

why is maintaining GD within a CBD diff?

A
  • only a small no. of breeding partners so inbreeding problems ➡ international catalogue is maintained
  • techs such as artificial insemination, embryo transfer, long term cryogenic storage of embryos allow new genetic lines to be intro w/o having to having to transfer animal to new location and cooperation.
193
Q

why are organisms born in captivity not be suitable for release in the wild?

A
  • diseases - may be a loss of resistance in CB pops and new diseases which they are not yet resistant to
  • Behaviour - much has to be learned through copying or exp
  • genetic races - the genetic makeup of captive animals can become so diff from the original pop that they cannot interbreed
  • habitat - in many cases, natural habitat may first be restored to allow CB pops to be reintroduced. If only a small, suitable pop exists it’s likely that there is already as many individs as the habitat can support
194
Q

International Union for Conservation of Nature?

A
  • intergovernmental organisation
  • (ICUN)
  • assists in securing agreements between nations
  • involved in the establishment of the CITES treaty
195
Q

the Rio Convention agreements?

A
  • the convention on Biological Diversity (CBD) requires countries to develop national strategies for sustainable development
  • the United Nations Framework Convention on Climate Change (UNFCCC) is an agreement between nations to take steps to stabilise greenhouse gas concs
  • the United Nations Conservation to Combat Desertification (UNCCD) aims to prevent the transformation of fertile land into desert and reduce effects of drought thru programmes of international co-op.

A Level Biology (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions