Speciation, Investigating Populations & Succession

Question 1

What is the first step in allopatric speciation?

Answer 1

Geographical isolation

Question 2

What happens to gene pools during allopatric speciation?

Answer 2

Separate gene pools / no interbreeding between populations

Question 3

What causes variation in allopatric speciation?

Answer 3

Variation due to mutation

Question 4

What environmental factors affect allopatric speciation?

Answer 4

Different environmental/abiotic/biotic conditions / selection pressures

Question 5

What does selection act on during allopatric speciation?

Answer 5

Selection for different/advantageous features/characteristics/mutation/allele

Question 6

What is the result of selection in allopatric speciation?

Answer 6

Differential reproductive success (selected organisms survive and reproduce)

Question 7

How do allelic frequencies change in allopatric speciation?

Answer 7

Leads to change in allelic frequencies

Question 8

What is the reproductive outcome of allopatric speciation?

Answer 8

Cannot breed/mate to produce fertile offspring

Question 9

Does sympatric speciation involve geographical isolation?

Answer 9

NOT geographical isolation

Question 10

What kind of isolation occurs in sympatric speciation?

Answer 10

Leads to reproductive isolation

Question 11

What happens to gene pools in sympatric speciation?

Answer 11

Separate gene pools / no interbreeding between populations

Question 12

What does selection act on in sympatric speciation?

Answer 12

Selection for different/advantageous features/characteristics/mutation/allele

Question 13

What is the result of selection in sympatric speciation?

Answer 13

Differential reproductive success (selected organisms survive and reproduce)

Question 14

How do allelic frequencies change in sympatric speciation?

Answer 14

Leads to change in allelic frequencies

Question 15

What is the reproductive outcome of sympatric speciation?

Answer 15

Cannot breed/mate to produce fertile offspring

Question 16

What causes variation in bacteria that can lead to resistance?

Answer 16

Variation/variety

Question 17

What genetic change leads to antibiotic resistance?

Answer 17

Mutation

Question 18

What example shows natural resistance in plants?

Answer 18

Some plants have allele to survive/grow/live in high concentration of copper/polluted soils

Question 19

What happens to adapted organisms?

Answer 19

(Differential) reproductive success / adapted organisms reproduce

Question 20

How does the resistant allele frequency change?

Answer 20

Increase in frequency of allele

Question 21

What happens to gene pools with resistance?

Answer 21

No interbreeding with other populations / separate gene pool / gene pool differs from other populations

Question 22

What happens first in succession?

Answer 22

Colonisation by pioneer species

Question 23

How do pioneer species affect the environment?

Answer 23

Pioneers cause change in environmental abiotic / biotic factors

Question 24

What do pioneers do to the environment?

Answer 24

Pioneers make the environment less hostile for new species

Question 25

How do new species affect previous species?

Answer 25

New species change/make conditions less suitable for previous species

Question 26

What happens to diversity during succession?

Answer 26

Change/increase in diversity/biodiversity

Question 27

What happens to stability during succession?

Answer 27

Stability increases (population/richness/abiotic factors)

Question 28

What is the final community in succession called?

Answer 28

Climax community

Question 29

What happens to species variety on coral reefs after succession?

Answer 29

Increase in variety/diversity of species/plants/animals

Question 30

What other terms describe this increase?

Answer 30

Increase in number of species/populations; or increase in species richness / biodiversity

Question 31

How does succession affect habitats on coral reefs?

Answer 31

Provides more/different habitats/niches

Question 32

How does succession affect food availability?

Answer 32

Provides greater variety/types of food

Question 33

How does succession affect hostility of environment?

Answer 33

Environment becomes less hostile

Question 34

How do you divide the area for random sampling?

Answer 34

Use a grid / split area into squares/sections

Question 35

How do you choose random sampling points?

Answer 35

Obtain random coordinates/numbers (calculator/computer/random numbers table/random number generator)

Question 36

What do you do at each sampling point?

Answer 36

Count number/frequency of plants in a quadrat

Question 37

How many quadrats should be sampled?

Answer 37

Large sample (20+ quadrats)

Question 38

How is population estimated from samples?

Answer 38

Calculate mean number per quadrat and multiply by total number of quadrats/sections in the area

Question 39

What tool is used in systematic sampling?

Answer 39

Transect/lay line/tape measure (from one side to the other)

Question 40

How are quadrats placed in systematic sampling?

Answer 40

At regular intervals along the line

Question 41

What is counted in quadrats during systematic sampling?

Answer 41

Count plants/percentage cover/abundance scale

Question 42

What alternative is done in systematic sampling?

Answer 42

Count plants touching the line/transect

Question 43

How do you choose quadrat positions?

Answer 43

Randomly (random numbers table/generator)

Question 44

How many quadrats are needed?

Answer 44

Large number/sample of quadrats (minimum 20)

Question 45

How is mean percentage cover calculated?

Answer 45

Divide total percentage cover by number of quadrats/samples/readings

Question 46

How do you randomly select quadrats on coral reef?

Answer 46

Random numbers table/generator

Question 47

How many quadrats are sampled?

Answer 47

Large number (>20)

Question 48

How do you calculate mean percentage cover?

Answer 48

Divide total percentage by number of quadrats/samples/readings

Question 49

What is the first step in mark-release-recapture?

Answer 49

Capture sample, mark and release

Question 50

What is important about the marking method?

Answer 50

Marking does not harm fish

Question 51

What is done after marking and releasing?

Answer 51

Take second sample and count marked organisms

Question 52

Write the formula for population estimation.

Answer 52

No in Population = (No in sample 1 × No in sample 2) ÷ Number marked in sample 2

Question 53

How does mark-release-recapture estimate population size?

Answer 53

Capture, mark and release sample

Question 54

What must marking not do?

Answer 54

Not harm fish or affect survival

Question 55

What must be allowed before the second sample?

Answer 55

Time for fish to randomly distribute

Question 56

What is the population formula?

Answer 56

Population = (number in first sample × number in second sample) ÷ number of marked fish in second sample

Question 57

Why might mark-release-recapture be unreliable in large lakes?

Answer 57

Less chance of recapturing fish

Question 58

What about fish distribution affects reliability?

Answer 58

Fish unlikely to distribute randomly/evenly

Question 59

How might fish behavior affect recapture?

Answer 59

Fish may remain in one area or congregate

Question 60

How do you decide how many quadrats to use?

Answer 60

Calculate running mean of results

Question 61

When do you stop sampling more quadrats?

Answer 61

When running mean levels out/shows little change on graph

Question 62

What else influences number of quadrats?

Answer 62

Enough for statistical test and reliable results

Question 63

What practical factor affects number of quadrats?

Answer 63

Time available for work

Question 64

What is carrying capacity?

Answer 64

Maximum number of individuals of each species an ecosystem can support

Question 65

Why conserve rainforests for species?

Answer 65

To conserve/protect species/plants/animals/organisms or biodiversity

Question 66

Why conserve rainforests for habitats?

Answer 66

To conserve/protect habitats/niches or provide many habitats/niches

Question 67

How do rainforests affect climate?

Answer 67

Reduces climate change

Question 68

What useful products come from rainforests?

Answer 68

Source of medicines/drugs/wood

Question 69

How do rainforests affect soil and water?

Answer 69

Reduces erosion/eutrophication

Question 70

What economic reason supports rainforest conservation?

Answer 70

Tourism