M4 CH11: biodiversity

Question 1

define biodiversity

Answer 1

the variety of living organisms in a specific area

Question 2

define habitat biodiversity

Answer 2

the number of different habitats in a given area

Question 3

define species richness

Answer 3

the number of different species living in a particular area

Question 4

define species evenness

Answer 4

the relative abundance of individuals of each species

Question 5

define genetic biodiversity

Answer 5

the variety of alleles within a species

Question 6

explain what genetic drift is

Answer 6

the loss of diversity over time by random chance

Question 7

outline the importance of genetic diversity

Answer 7

creates a larger gene pool
more adaptations and survivals
resistance to biotic factors- disease

Question 8

explain what a locus is

Answer 8

the position of a gene on a chromosome

Question 9

explain the term natural selection

Answer 9

1. reproduction creates more individuals than the environment can support.
2. competition for food occurs as a consequence
3. limited food acts as a selection pressure for organisms
4. individuals with favourable phenotypes have a selective advantage
5. these organisms outcompete others for food, and survive and reproduce
6. these favourable alleles are passed onto future generations

Question 10

state 3 causes of low genetic diversity.

Answer 10

1. genetic bottleneck event
2. the founder effect
3. genetic drift

Question 11

state the factors affecting genetic biodiversity.

Answer 11

mutations
natural selection
genetic bottlenecks
founder effect
genetic drift
gene flow

Question 12

explain what a genetic bottleneck is.

Answer 12

natural disaster
causes a large decrease in population size
reduces the gene pool
results in reduced genetic variation

Question 13

explain what the founder effect

Answer 13

when a few individuals of a species take over a new area, their offspring experience a loss in genetic variation. this results in rarer alleles becoming more common in the population.

Question 14

explain what genetic drift is

Answer 14

random fluctuations in the frequencies of alleles between generations
can cause some traits to become dominant, some to disappear

Question 15

explain why genetic drift is more pronounced in small populations.

Answer 15

because the gene pool is smaller

Question 16

explain what gene flow is

Answer 16

the transfer of alleles from one population to another when individuals of one population migrate

Question 17

state some human activities which have changed the genetic diversity of organisms

Answer 17

selective breeding
captive breeding
cloning

Question 18

explain what genetic polymorphism is

Answer 18

genes which have multiple alleles

Question 19

explain what a polymorphic gene is

Answer 19

a gene with more than one allele

Question 20

synoptic: state the name of the process that can be used to separate DNA fragments based on their size. explain the process.

Answer 20

electrophoresis
add expln

Question 21

give the equation to calculate the proportion of polymorphic gene loci

Answer 21

number of polymorphic loci / total number of loci

Question 22

state the 2 types of sampling that can be used.

Answer 22

random
non random

Question 23

state the most appropriate equipment to gather a random sampling of flying organisms

Answer 23

sweeping nets

Question 24

explain what pitfall traps are
what type of sampling
what organisms are gathered in them

Answer 24

cans/jars buried in the ground
random sampling method
small ground-bound organisms

Question 25

explain what pooters are
what type of sampling
what organisms are gathered in them

Answer 25

plastic/glass containers, 2 tubes sticking out of them. suction mechanism to gather
random sampling
INSECTS

Question 26

explain what a tullgren funnel is
type of sampling
organisms gathered

Answer 26

funnel with light bulb above & container below- used for soil samples
random sampling
invertebrates living in soil

Question 27

explain what kick sampling is
type of sampling
organisms gathered

Answer 27

net placed on stream bed in aquatic ecosystems
random sampling
aquatic organisms

Question 28

Queen of Sampling Plays Poker Till King comes home
write out acronym, apply and explain (linked to biodiversity)

Answer 28

random sampling methods
quadrat- plant sampling
sweeping nets: flying insects/long grass samples
pitfall traps: ground jars- insects on ground
pooters: suction mechanism: insects
tullgren funnel: for soil samples/ light bulb and funnel
kick sampling: net on stream bed (aquatic sampling)

Question 29

describe opportunistic sampling (3)

Answer 29

non random sampling
picking and choosing sampling locations
usually dictated by convenience

Question 30

describe stratified sampling. (2)

Answer 30

non random sampling
dividing up area for sampling
done when there is habitat variety- sample sizes are proportional to the proportion of each habitat relative to the whole area

Question 31

describe when you would use systematic sampling

Answer 31

when there is a clear change in the conditions as you move across the area

Question 32

describe the 2 types of systematic sampling

Answer 32

line transect: tape measure, recording at equal distances
belt transect: quadrats placed at regular interval across the length of the area

Question 33

line transect:
random or non random?
systematic, opportunistic or stratified?
qualitative or quantitative?

Answer 33

non random
systematic
qualitative

Question 34

belt transect:
random or non random?
systematic, opportunistic or stratified?
qualitative or quantitative?

Answer 34

non random
systematic
quantitative

Question 35

what information does a belt transect give that random quadrat sampling does not

Answer 35

records the change as you move across the area (systematic) as oppose to random points in the area

Question 36

describe how to use a random frame quadrat

Answer 36

place quadrat randomly in area using co ordinates (to ensure completely random)
count species richness and evenness
(n/of species, n/of each species)