Brainscape's Knowledge GenomeTM

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


See full index

AS Level Biology > Topic 4.2.1 Biodiversity > Flashcards

Topic 4.2.1 Biodiversity Flashcards

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

What is a Habitat?

A

The place where an organism lives - organisms are often well-adapted to their habitats

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

What is Biodiversity?

A
  • all plant, animal, fungus and microorganism species worldwide
  • the genes these species contains
  • the ecosystems they form part of
  • number of individuals and the number of places they are found
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is Habitat Biodiversity?

A

The range of habitats in which different species live

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

What is Species Biodiversity?

A
  • Species Richness

- no. of different species living in an area

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

What is Genetic Biodiversity?

A
  • the variety of genes that form a species
  • many individuals in the same species have the same genes
  • for some genes different alleles exist
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is Species Richness?

A

the number of species found in a habitat - more species=richer habitat

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

What is Species Evenness?

A

a measure of the relative abundance or number of individuals in each species

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

What is the formula for the ‘mark-and-recapture-technique’?

  • Total Population Formula
A

(C1 x C2) / C3

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

What sample is labelled as C1 in the ‘mark-and-recapture-technique’?

A

The number initially captured and harmlessly marked

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What sample is labelled as C2 in the ‘mark-and-recapture-technique’?

A

The number captured the second time around after C1 has been released for a period of time

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

What sample is labelled as C3 in the ‘mark-and-recapture-technique’?

A

The number already marked within C2

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

Advantages of the ‘mark-and-recapture-technique’?

A
  • quick to carry out

- measure large populations in less time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Disadvantages of the ‘mark-and-recapture-technique’?

A
  • can be unreliable

- needs to be repeated

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

What is ‘Simpson’s Index of Diversity’?

A

a better method for measuring habitat diversity

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

What does ‘Simpson’s Index of Diversity’ take into account?

A
  • species richness

- species evenness

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

What is the formula for ‘Simpson’s Index of Diversity’?

A

D = 1 - [sum (no. of individuals of a particular species / no. of individuals of all species)^2 ]

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

n in the ‘Simpson’s Index of Diversity’ formula represents what?

A

no. of individuals of a particular species or % cover for plants

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

N in the ‘Simpson’s Index of Diversity’ formula represents what?

A

no. of individuals of all species or % cover for plants

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

What does a high value from Simpson’s Index of Diversity show?

A
  • a diverse habit

- the habitat is stable and able to withstand change

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

What does a low value from Simpson’s Index of Diversity show?

A
  • the habitat is dominated by a few species

- a small change to the environment that affects one of the dominant species could damage or destroy the whole habitat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is an abiotic factor?

A

Factors that don’t have living organisms as a source

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

Name some examples of abiotic factors

A
  • wind speed
  • light intensity
  • relative humidity
  • pH
  • temperature
  • oxygen levels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How does wind speed affect biodiversity?

A
  • increases the supply of CO2 to the plant
  • increases transpiration rate and therefore water loss
  • can cause mechanical damage to plants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How is wind speed measured?

A

With an anemometer (ms-1)

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

How does light intensity affect biodiversity?

A

-plant species have evolved for optimum growth in the light available in their climate or habitat

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

How is light intensity measured?

A

With a light meter (Ix)

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

How does relative humidity affect biodiversity?

A
  • most plants are killed by water Lolll logging meaning they can’t respite
  • big plants are adapted to growing in wet conditions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How is relative humidity measured?

A

With a humidity sensor (mgdm-3)

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

How does temperature affect biodiversity?

A
  • animals and plants have evolved to grow healthily at their optimum temperature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How is temperature measured?

A

Temperature probs (degrees Celsius)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the two types of sampling in plants?

A
  • random

- non-random

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

What is random sampling?

A
  • involves selecting individuals by chance

- each individual in the population has an equal chance of being selected

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

How is random sampling carried out?

A

using random number tables, generators or computers

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

What is non-random sampling?

A
  • the sample taken is not chosen at random

- random sampling can be divided into three main techniques?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are the three main techniques for non-random sampling?

A
  • opportunistic
  • stratified
  • systematic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is opportunistic sampling?

A
  • the weakest form of sampling
  • not representative of the population
  • uses organisms that are conveniently available
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what is stratified sampling?

A
  • the population is divided into different strata based on particular characteristics
  • random sample is taken from each strata proportional to its size
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the definition of a ‘strata’?

A

a sub-group

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

What is systematic sampling?

A
  • different areas within an overall habitat are identified, sampled separately
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is a transect?

A
  • a line taken across the habitat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How does a Line Transect work?

A
  • involves making a line along the ground between two poles and taking samples at specified points along the line
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

How does a Belt Transect work?

A
  • two parallel lines are marked, samples are taken from the area between two lines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Does a line or a belt transect provide more information?

A

belt transect

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

What type of transect is used in a large habitat?

A
  • line transect
  • record the plants touching the line at set intervals
  • belt transect
  • place quadrats along the line and record the data
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What are the two types of belt transect?

A
  • interrupted

- continuous

46
Q

How does an interrupted belt transect work?

A
  • quadrats set at intervals along the line

- record data

47
Q

What type of data does an interrupted belt transect provide?

A
  • quantitative data at intervals across the habitat
48
Q

How does a continuous belt transect work?

A
  • quadrats beside the line without any intervals between them
49
Q

What type of data does a continuous belt transect provide?

A
  • quantitative data in a band or belt across the habitat
50
Q

How are plants usually sampled?

A

using quadrats and the random sampling technique

51
Q

When would a line or belt transect be best used?

A

in an environment that varies where you want to study the distribution of organisms

52
Q

What are the three ways to sample when using frame quadrats?

A
  • Density
  • Frequency
  • Percentage Cover
53
Q

What is Density sampling when using a frame quadrat?

A
  • used when plants can be easily counted
  • each individual plant is counted so the results are far more accurate than an estimation like infrequency and percentage cover
54
Q

What is Frequency sampling when using a frame quadrat?

A
  • an estimate used when species are hard to count

- counting the number of squares that a species is present in

55
Q

What is Percentage Cover sampling when using a frame quadrat?

A
  • an estimate by eye of an area within a quadrat that a plant species covers
  • can be quickly collected
56
Q

How do Point Quadrats work?

A
  • a frame containing a horizontal bar
  • long pins can be pushed through the bar to reach the ground at set intervals
  • each species of plant the pin touches is recorded
57
Q

What is the impact of sampling bias on sampling and reliability?

A

reduces how representative the sample is of the whole habitat

58
Q

What is the impact of chance on sampling and reliability?

A

a small sample size increases the likelihood of chance playing a part in the reliability - should always take from a larger sample

59
Q

How do you sample biodiversity in animals?

A
  • pitfall traps
  • pooter
  • kick sampling
  • sweep net
  • tree beating
60
Q

What are pitfall traps?

A
  • used to catch small invertebrates such as beetles, spiders and slugs
  • a hole deep enough so the samples can’t climb back out is dug into the ground which insects fall into
61
Q

What is a pooter?

A
  • used to catch small insects for identification

- you put it in your mouth and suck the insects into the holding chamber through the inlet tube

62
Q

What is kick sampling?

A
  • used to study the organisms living in a river bank

- the river bank is kicked for a period of time to dislodge the organisms

63
Q

What is a sweep net?

A
  • used to catch insects in areas of long grass
64
Q

What is tree beating?

A
  • used to sample invertebrates living in or on trees

- a large white cloth is stretched out under the tree and the tree is shaken or beaten

65
Q

What technique is often used to estimate animal population size?

A

capture-mark-release-recapture

66
Q

What are alleles?

A
  • all members of the same species share the same genes

- different versions of the same genes are called alleles

67
Q

What is another name for alleles?

A

polymorphisms

68
Q

What is genetic biodiversity?

A
  • differences in the alleles creates genetic biodiversity within the species
  • the more alleles present in a population the more genetically biodiverse the population
69
Q

Where are genes found?

A
  • a gene can be found in a particular position on a chromosome
  • different individuals may have different alleles for a particular gene
70
Q

What is the point at which a gene can be found on a chromosome called?

A

the locus (plural - loci)

71
Q

How does genetic biodiversity increase?

A

the number of possible alleles in a population also increase

72
Q

How does mutation affect genetic biodiversity?

A

creates greater variation within the base DNA present in a particular species - more alleles present in the genes

73
Q

How does interbreeding affect genetic biodiversity?

A

different species that contain varying genes and alleles breed which will increase genetic biodiversity of their offspring

74
Q

How does genetic biodiversity decrease?

A

the number of possible alleles in a population much also decrease

75
Q

How does selective breeding lead to a decrease in genetic biodiversity?

A
  • choosing the exact genes that will be passed to the offspring decreases variation
  • doesn’t allow for natural mutations or interbreeding
76
Q

How do captive breeding programmes lead to a decrease in genetic biodiversity?

A
  • decreases the genes available to create variation through reproduction
77
Q

How do rare breeds decrease genetic biodiversity?

A
  • only a limited gene pool available for reproduction through the limited species density
  • not many organisms within the species
78
Q

How does artificial cloning decrease genetic biodiversity?

A
  • cloning an identical copy of an organism

- eliminates all variation

79
Q

How does natural selection decrease genetic biodiversity?

A
  • eliminates the less advantageous alleles within a species as they are less likely to survive and reproduce in their habitat
80
Q

How do genetic bottlenecks decrease genetic biodiversity?

A
  • a catastrophic event eliminates a large portion of the genetic variation within a species
  • only a few organisms and their genes can reproduce
81
Q

How does the founder effect decrease genetic biodiversity?

A
  • a more limited gene pool available for reproduction will limit the variation within the species population
  • over time mutation will increase genetic biodiversity
82
Q

How does genetic drift decrease genetic biodiversity?

A
  • involves the loss of alleles from a population by chance

- random fluctuation in allele frequencies in small populations

83
Q

What is polymorphism?

A

a discontinuous genetic variation resulting in the occurrence of several different forms or types of individuals among the members of a single species

84
Q

How do you measure genetic biodiversity within a population?

A
  • gel electrophoresis

- measures the polymorphic genes (more than one allele)

85
Q

What are the steps of Gel Electrophoresis?

A
  1. Restriction enzymes cleave DNA into smaller segments of various sizes
  2. DNA segments are loaded into wells in a porous gel - the gel floats in a buffer solution within a chamber between two electrodes
  3. When an electric current is passed through the chamber, DNA fragments move toward the positively-charged cathode
  4. Smaller DNA segments move faster and father than larger DNA segments
86
Q

What three types of reason are there to maintain genetic biodiversity?

A
  • aesthetic reasons
  • economic reasons
  • ecological reasons
87
Q

What aesthetic reasons are there for maintaining genetic biodiversity?

A
  • enriches our lives
  • provides inspiration
  • recovery from injury or stress
88
Q

What economic reasons are there for maintaining genetic biodiversity?

A
  • soil erosion and desertification
  • loss of potential medicines or chemicals
  • soil depletion from monoculture - increasingly dependant upon herbicides and fertiliser
  • protects against biotic stresses - disease, natural disasters
  • promote tourism
  • greater varieties allows for cross breeding for favourable characteristics
  • conserve organisms we use to make things
89
Q

What ecological reasons are there for maintaining genetic biodiversity?

A
  • interdependence - all organisms depend on each other in a food chain
  • keystone species - some species play a key role in the structure of the community
90
Q

What are the three main factors affecting biodiversity?

A
  • deforestation
  • agriculture
  • climate change
91
Q

What causes deforestation?

A
92
Q

How does deforestation affect biodiversity?

A
93
Q

What causes issues surrounding agriculture?

A
94
Q

How does agriculture affect biodiversity?

A
95
Q

What causes climate change?

A
96
Q

How does climate change affect biodiversity?

A
97
Q

What is conservation in-situ?

A
98
Q

What is an example of in-situ conservation?

A
99
Q

What active management techniques are used in wildlife reserves?

A
100
Q

What are some benefits of in-situ conservation?

A
101
Q

What is conservation ex-situ?

A
102
Q

What are some examples of ex-situ conservation?

A
103
Q

Describe botanical gardens as a method of ex-situ conservation.

A
104
Q

Describe seed banks as a method of ex-situ conservation.

A
105
Q

Describe captive breeding as a method of ex-situ conservation.

A
106
Q

What are some advantages of Captive Breeding Programmes?

A
107
Q

What are some disadvantages of Captive Breeding Programmes?

A
108
Q

What is the International Union for the Conservation of Nature?

A
109
Q

What was the Rio Convention?

A
110
Q

What was the Countryside Stewardship Scheme?

A

AS Level Biology (15 decks)

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