Brainscape's Knowledge GenomeTM

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


See full index

A-Level Biology > Module 7: Populations, Evolution, Inheritance > Flashcards

Module 7: Populations, Evolution, Inheritance Flashcards

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

species definition

A

group of organisms with similar characteristics that can interbreed to produce living fertile offspring

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

population definition

A

all of the individuals of a particular species in a particular place

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

community definition

A

all the population of different species in a particular place

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

ecosystem definition

A

a mix of different communities and habitats and how they interact based on biotic and abiotic factors

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

ecological niche definition

A

organisms role/position in an ecosystem

in terms of its biotic and abiotic factors

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

why can two species not occupy the same niche

A

interspecific competition will take place for the limiting factors/resources (abiotic and biotic), better adapted species will outcompete the less adapted at the expense of the less adapted species.
competitive exclusion principle

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

how to sample a plant species over a large area

A

obtain a map of the area
divide the map into grids
select a large number of coordinates using a running mean
select a random set of coordinates using a random number generator
place a quadrat in each coordinate
measure abundance of the plant species in each quadrat and calculate frequency or percentage cover
calculate an average for the whole area

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

how to samples plant species along a path

A

use a transect
place tape along the path, count the number of plants touching the tape (line transect)
place tape along the path, at regular intervals along the tape place a quadrat and measure the abundance within the quadrat (belt transect)

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

how to sample animals species in an area

A 
mark release recapture 
collect a sample of animals 
mark them using non-toxic marker 
release them
after sufficient time for them to re-mix with the population recapture 
count the number in the second set and count the number of species that are marked
number in sample 1 x number in sample 2 
all divided by marked in sample 2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

assumptions of mark release recapture

A 
no births or deaths 
no immigration ort emmigration
marked animals mix evenly with population
mark is non-toxic 
mark doesn't come off 
large population
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

3 stages of population growth

A

slow/lag phase
rapid/log phase
stationary phase

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

lag phase

A

species becomes adapted to new environment

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

rapid phase

A

species are adapted
abundant resources
doubling with reproduction
birth rate > death rate

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

stationary phase

A

resources become limited
intraspecific competition
birth rate= death rate

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

abiotic definition

A

non-living factors

light, temperature, water, O2/CO2, minerals, pH, living space

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

biotic definition

A

living factors

predator, prey, mates, competition, disease

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

competition definition

A

where organisms compete for resources, both biotic and abiotic

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

2 types of competition

A

intraspecific

interspecific

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

intraspecific definition

A

occurs between organisms of the same species, only occurs when resources become limited, leads to natural selection and adaptation

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

interspecific definition

A

occurs between organisms of different species, can happen at any time even if resources aren’t limited
leads to formation of climax communities

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

predator prey relationships

A 
prey increases 
more food for predator 
predator increases 
predators eat more of prey 
prey decreases
less food for predator 
predator decreases 
less prey eaten 
prey increases in number
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

succession definition

A

how an ecosystem changes over time, change in species diversity and habitat diversity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what does succession rely on

A

the environment being made less hostile by present species via death and decomposition leading it to being outcompeted and replaced by larger better adapted species

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

2 types of succession

A

primary

secondary

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

primary succession definition

A

occurs on new land

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

secondary succession definition

A

occurs on previously colonised land that has become bare e.g. after a fire

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

process of primary succession

A

pioneer species colonies an inhospitable environment
the pioneer species improves a named condition because they are (list a feature)
over time the land erodes and soil will form, pioneer species are outcompeted by primary coloniser
primary coloniser will continue to improve named conditions
secondary coloniser will outcompete primary coloniser
climax community is reached

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

properties of succession

A

species diversity increases (peaks just before climax)
habitat diversity increases
environment becomes less hostile
food chains become more complex and biomass increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

primary succession vs secondary succession

A

secondary starts from small plants not pioneer species
so soil and nutrients are already present
secondary is faster

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

how can conservation prevent succession

A

used to prevent formation of woody forests

involves deforestation, burning trees, grazing and using pesticides

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

biodiversity definition

A

range and variety of genes, species and habitats within a particular region

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

species diversity definition

A

number of different species and the number of individuals of each species within a community

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

genetic diversity definition

A

variety of genes and allele frequency possessed by individuals that make up one species

35
Q

ecosystem diversity

A

range of different habitats within a particular area

36
Q

preservation definition

A

maintaining individuals, populationd and ecosystems in their current state without the exploitation of their natural resources

37
Q

conservation definition

A

allowing ecosystems to evolve naturally without resources being overused

38
Q

how to conserve an area

A

active human management
in situ
ex situ

39
Q

in situ

A

whole ecosystems and landscapes
within habitat
monitoring succession

40
Q

ex situ

A

outside natural habitat

individual endangered species in zoos

41
Q

which stage of succession do you manage

A

mid succession
not dominated by one species
not very hostile
can support multiple species/habitats/food sources as there is a higher biodiversity

42
Q

evolution definition

A

change in allele frequency in a population

43
Q

2 types of evolution

A

adaptation and speciation

44
Q

adaptation definition

A

species adapting to changes in its environment, driven by natural selection, where most of the individuals in the species will have the favourable allele/characteristic for that environment

45
Q

process of adaptation

A

variation in species population
new allele arises due to random mutation
environment applies a selection pressure on the population
those with favourable characteristics/alleles survive at the expense of those less well adapted
ones that survive will reproduce to pass on their favourable alleles
if this happens for many generations then that characteristic will become most common
favourable allele becomes more frequent

46
Q

3 types of selection

A

stabilising
directional
disruptive

47
Q

stabilising selection

A

when environment favours individuals with the most common characteristic
at the expense of the extremes (favoured against)
most common will increase in proportion
range (standard deviation) will decrease
e.g. birth weight

48
Q

directional selection

A 
when the environment favours one of the extremes
causes curve to shift to the right 
mean favoured against 
overtime this will become most common
e.g. antibiotic resistance
49
Q

disruptive selection

A

when the environment changes between both extreme conditions
individuals on both extremes are favoured at different times and increase in number
the middle/average will decrease in number
e.g. fur length

50
Q

Speciation definition

A

Process by which new species arise from existing species

51
Q

2 types of speciation

A

Allopatric

Sympatric

52
Q

Allopatric speciation

A

Speciation driven by geographical isolation

53
Q

Describe allopatric speciation

A

Start with a population of species
variation in population
Population separated into different groups by geographical isolation
Each group exposed to different enironments/selection pressures
Each group undergoes different directional selections
Each group changes so much in genetic diversity that they can’t interbreed with each other to produce living fertile offspring= different species
Changes include different courtship behaviours or incompatible gametes

54
Q

Sympatric speciation

A

Speciation occuring in the same geographical area driven by random mutation

55
Q

Inheritance definition

A

Offspring inheriting a combination of alleles ( paternal and maternal) for each gene which will help determine characteristics

56
Q

gene definition

A

Section of DNA that codes for a protein

57
Q

Allele definition

A

Version of a gene

58
Q

Dominant allele definition

A

Allele that is always expressed if present

59
Q

Recessive allele definition

A

Allele that is only expressed if 2 are present

60
Q

Genotype definition

A

Genetic makeup of an organism, combination of alleles for a particular gene

61
Q

Phenotype definition

A

Expressed/observed characteristic
Continuous then determined by genotype and environment
Discontinuous then only genotype

62
Q

Homozygous definition

A

Having 2 of the same alleles

63
Q

Heterozygous definition

A

Having 2 different alleles

64
Q

Monohybrid inheritance

A

Inheritance dealing with one characteristic

65
Q

Examples of monohybrid inheritance

A

Dominant/recessive
Codominant
Multiple allele
Sex linkage

66
Q

Expected ratio monohybrid dominant/recessive

A

3:1 dominant to recessive

67
Q

Why are observed ratios different from expected ratios

A

Random fertilisation of gametes
Small sample size
Mutation
Selection

68
Q

How can 2 parents with dominant characteristic have offspring with recessive characteristic

A

If both are heterozygotes

25% chance of homozygous recessive

69
Q

What is co-dominance

A

When 2 different dominant alleles are inherited both will be expressed in the phenotype

70
Q

What are multiple alleles

A

Gene has more than 2 alleles

Blood group

71
Q

Alleles for blood group

A 
I^A, I^B, I^O
I^A gives A antigen 
I^B gives B antigen 
I^O gives no antigen 
I^A and I^B are codominant 
I^O is recessive
72
Q

Genotypes/phenotypes for blood group A

A

I^A I^A

I^A I^O

73
Q

4 blood groups

A

A
B
AB
O

74
Q

Genotype/phenotype for group B

A

I^B I^B

I^B I^O

75
Q

Genotypes/phenotypes for group AB

A

I^A I^B

76
Q

Genotype/phenotype for blood group O

A

I^O I^O

77
Q

Who can receive blood from whom

A

A from A and O
B from B and O
AB from A, B, AB and O
O only from O

78
Q

What is dihybrid inheritance

A

Inheritance with two characteristics

79
Q

Examples of dihybrid inheritance

A

Dominant/recessive
Autosomal linkage
Epistasis

80
Q

Expected ratio dihybrid dominant/recessive

A

9 DD
3 DR
3 RD
1 RR

81
Q

What does hardy weinberg principle calculate

A

Frequency of allele in a population

82
Q

What does HWP assume

A 
That frequency wont change over time based on:
Isolated population 
Large population 
Random mating
No mutation 
No selection
83
Q

HWP

A 
p= frequency of dominant allele
q= frequency of recessive allele
p+q= 1, all population 
p^2 homo dominant
2pq hetero
q^2 homo recessive
p^2 +2pq dominant
p^2 + 2pq + q^2= 1

A-Level Biology (14 decks)

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