4.2.1: Biodiversity

Question 1

Biodiversity

Answer 1

the variety of life on earth/of species in an environment.

Question 2

Types of biodiversity

Answer 2

• Species
• Habitat
• Genetic diversity

Question 3

Species

Answer 3

Two individuals which can interbreed to produce fertile offspring; basic units of biological classification.

Question 4

Types of non-random sampling

Answer 4

• Stratified
• Systematic
• Opportunistic

Question 5

What is stratified sampling?

Answer 5

Population divided into strata (sub-groups) e.g. male/female. Random samples then taken from each group.

Question 6

What is opportunistic sampling?

Answer 6

Uses organisms which are conveniently available e.g. trapping

Question 7

What is systematic sampling?

Answer 7

Different areas within a habitat are identified and sampled separately, e.g. belt transect.

Question 8

Methods of sampling living organisms

Answer 8

1) Kick sampling
2) Sweep netting
3) Collecting from trees
4) Longworth trap
5) Pitfall trap
6) Cover trap
7) Water trap
8) Tullgren funnel
9) Light trap
10) Mark-release-recapture

Question 9

Genetic biodiversity

Answer 9

Differences between individuals of the same species

Question 10

Habitat biodiversity

Answer 10

Range of habitats in which a species lives

Question 11

Species biodiversity

Answer 11

Difference between species (e.g. functional differences of bacteria involved in decay and those involved in digestion)

Question 12

What does a low Simpson’s diversity index mean?

Answer 12

Habitat has low biodiversity

Environment less stable, less able to withstand change

Question 13

Information needed to calculate Simpson’s index

Answer 13

Number of individuals of all species in area being sampled (100% cover for plants)
Identify all species present

Question 14

Species richness

Answer 14

Number of different species in area

Question 15

Species eveness

Answer 15

How close in numbers each species in area is

Question 16

High Simpson’s index

Answer 16

Area is biodiverse
More stable
Able to better withstand change

Question 17

Gene pool

Answer 17

Distribution of different alleles in a population

Question 18

Gene

Answer 18

Length of DNA which codes for a specific protein

Question 19

Allele

Answer 19

Variation of a gene

Question 20

Factors which increase genetic biodiversity

Answer 20

Mutation

Interbreeding between different populations

Question 21

Factors which decrease genetic biodiversity

Answer 21

• Selective breeding
• Rare breeds
• Captive breeding
• Cloning
• Natural seletion
• Genetic bottle necks (only a few survive an event)
• Founder effect (small no. create new population)
• Genetic drift (some alleles will be completely lost naturally)

Question 22

Polymorphic genes

Answer 22

Genes with more than 1 allele

Question 23

Factors affecting biodiversity

Answer 23

• Deforestation
• Agriculture –> monoculture
• Climate change
• Humans: pollution, hunting, introduction of new species (cane toad to Australia)

Question 24

Keystone species

Answer 24

A species which plays a critical role in the ecological community

Question 25

In situ conservation

Answer 25

Conservation of species in their natural habitat

Question 26

Ex situ conservation

Answer 26

Conservation of species outside of their natural habitat

Question 27

Pros of in situ

Answer 27

✔︎ Species will have all necessary resources ✔︎ Cheap ✔︎ Bigger breeding populations can be kept ✔︎ Species will have more space ✔︎ Species will continue to evolve

Question 28

Cons of in situ

Answer 28

✘ Environment may need restoring | ✘ Hard to control poaching

Question 29

Cons of ex situ

Answer 29

✘ Small gene pool ✘ Often, cannot release = not adapted to disease, have not learned to hunt, cannot interbreed with wild population, habitat may have been totally destroyed

Question 30

Spearman's rank results

Answer 30

Between 0 and 1 | Higher = stronger correlation (less spread of results)

Question 31

How to communicate the results of stats tests

Answer 31

1) Find critical values 2) Comment on significance (i.e. above critical value) 3) Comment on probability (p= 0.0.5 --> 5% probability that correlation due to chance)

Question 32

d (Spearman's)

Answer 32

Rank difference

Question 33

n (Spearman's)

Answer 33

Number of species

Question 34

N (Simpson's)

Answer 34

Total number of individuals found

Question 35

n (Simpson's)

Answer 35

Number of individuals of a species found

Question 36

Why conserve species? (economic reasons)

Answer 36

* Regulation of atmosphere and climate * Formation/fertilisation of soil * Reducing soil depletion * Recycling of nutrients (carbon, nitrogen) * Crop pollination * Possible sources of medicines

Question 37

Why conserve species? (ethical & aesthetic reasons)

Answer 37

* Enjoyment of nature --> wellbeing * Every organism has right to survive and live where they adapted to live * Physical, intellectual, emotional health

Question 38

How does the founder effect decrease genetic biodiversity?

Answer 38

* Small number of individuals create a new colony that is geographically isolated from the original * Increased prevalence of diseases caused by recessive alleles

Question 39

How does genetic drift decrease genetic biodiversity?

Answer 39

* Which alleles are passed from parent to offspring is random * Frequency varies but some alleles are lost forever

Question 40

How does a genetic bottleneck decrease genetic biodiversity?

Answer 40

• Genetic bottleneck: only a few individuals within a population survive an event or change

Question 41

How does natural selection decrease genetic biodiversity?

Answer 41

• Only individuals with advantageous alleles survive to reproduce

Question 42

Similarities between the founder effect and genetic bottlenecking?

Answer 42

* Both followed by genetic drift which results in change of allele frequencies * Initially, genetic biodiversity is lost * Both involve small numbers of individuals breeding with each other * Both may result in a new population carrying alleles that are unlikely to be representative of the original group

Question 43

Differences between the founder effect and genetic bottlenecking?

Answer 43

Bottlenecking involves individuals dying | The founder effect involves ecological separation of individuals