Adaptations Flashcards
(136 cards)
1
Q
What is gene flow?
A
The movement of genes in and out of a population (could be due to migration)
2
Q
What is a gene?
A
A sequence of DNA nucleotides that code for a specific amino acid
3
Q
What is an allele?
A
Genes occupying the same locus on a homologus chromosome, coding for the same trait
4
Q
What is a gene pool?
A
All the genes and alleles present in a reproducing population
5
Q
What is a species?
A
A group of potentially interbredding populations with a common gene pool
6
Q
How do multiple gene pools exist for one species?
A
The species are geographically isolated
7
Q
What organisms contribute to a population’s gene pool?
A
All the individuals that reproduce
8
Q
What is genetic equillibrium?
A
When all members of a population have an equal chance to contribute to the future gene pool (theoretical because of natural selection)
9
Q
What are the causes of genetic variation?
A
Mutations (duing replication or viral infection), environmental factors interfering with genes, sexual reproduction through meiosis (crossing over and independent assortment) and random fertilistion
10
Q
What is a selection pressure?
A
A condition that affect allele frequency (e.g. predation)
11
Q
What causes evolution?
A
Selection pressures and mutations
12
Q
What is a mutation?
A
Alterations in the DNA of chromosomes that can cause physiological, anatomical and behavioural changes
13
Q
When can mutations occur?
A
During replication or as a result of a mutagen
14
Q
What are the three types of mutations?
A
Beneficial, neutral, harmful
15
Q
What is natural selection?
A
Process where certain inherited traits of a population are favoured due to selection pressures, and change genetic make up of a population over time
16
Q
What is an example of natural selection?
A
After the industrial revolution, darker moths become more likely to survive, so the trait became more prominent
17
Q
What is ‘fitness’?
A
An organism’s relative ability to survive
18
Q
What is sexual selection?
A
Intraspecies struggle between members of the same species for the possession of another species.
19
Q
How can creatures adapt to sexual selection?
A
Become more attractive or intimidate other individuasl
20
Q
What is the question structure for natural selection?
A
- There was variation within a specific trait of a species
- Species produce more offspring than an environment can support
- There was the selection pressure of _
- Individuals with _ had a survival advantage bc _
- They are more likely to survive and reproduce, thus this trait becomes more prominent in the species
21
Q
What is genetic drift?
A
Random change in the frequency of alleles from generation to generation
22
Q
What populations is genetic drift often a part of?
A
Small populations that are isolated. Survivors of bottleneck events are more prone
23
Q
What is a population bottleneck?
A
Population becomes dramatically reduced due to certain events. Only a small number of individuals remain in the gene pool to contribute their genes to the enxt generation. The sample size is skewed, and allele frequencies are altered.
24
Q
What is the surviving population of a bottleneck often exposed to?
A
Inbreeding and genetic drift
25
What is an example of a bottleneck species?
Cheetahs. they have low genetic diversity now
26
Effects of low genetic diversity due to population bottleneck in cheetahs
Sperm abnormality, decreased fertility, increased cub mortality
27
What is the founder effect?
Loss of genetic diversity that occurs when a small number of individuals migrate away from the population
28
What is the effect of a colonizing/founder population?
Small and non-representative sample of alleles from the parent population's gene pool. Evolve in a different direction to parent population. Subject to effects of genetic drift
29
What are founder species dispersal dependent on?
Prevailing winds. Other than that, low or limited mobility
29
What is the effect of isolated populations?
Inbreeding and therefore reduced genetic diversity
29
Where is the founder effect commonly seen?
Populations of islands colonised by mainland populations
30
What happens with populations are isolated?
Little to no gene flow to introduce new alleles.
30
Example of isolated population
Tasmania Devil. Theire isolated nature makes them have reduced genetic diversity, which probably increased their susceptibility to facial tumour disease
30
What is speciation?
The process of populations becoming distinct species as isolation causes natural selection to favour different traits
31
What is a fragmented population?
When events cause a large population to be isolated into two or more separate populations
32
What does habitat fragmentation cause?
Reduced gene flow between populations, therefore inbreeding and genetic diversity loss
33
What species has genetic rescue worked for?
Mountain Pygmy Possum
34
How did genetic rescue of the Mountain Pygmy Possum work?
introducing new males, habitat and predator control
35
What is an abiotic factor?
A non-living factor that impacts the survival of a species
36
Examples of abiotic factors
Water, temperature, pH, salinity
37
What is a biotic factor?
Living factor that impacts the survival of a species in its invironment
38
Example of a biotic factor?
Competitors, predators, parasites, pathogens
39
What is the optimal range?
The range of an abiotic factor that allows for the best functioning of an organism
40
What is the tolerance range?
Includes the sides of the optimal range, which is the zone of physiological stress. Life is possible but difficult
41
What are the zones of intolerance?
The range in which survival is not possible for an organism
42
What is an adaptation?
Characteristics that increase the likelihood of survival within a species
43
What is a structural adaptation?
Anatomical adaptation
44
Another word for structural?
Morphological or anatomical
45
What is a physiological adaptation?
Change in the function of parts of the body
46
Another word for physiological
Functional
47
What is a behavioural adaptation?
Activity of the whole organism (learnt or innate)
48
What are some plant adaptations to an arid environment?
Fewer stomata, stomatal hair to create humid microclimate, sunken or protected stomata, leaf rolling, reduced leaf SA, leaf orientation away from sun, thick waxy cutcile, extensive underground root system
49
Why is having fewer stomata an adaptation to an arid environment?
Less water leaves the plant
50
Why is having stomatal hairs an adaptation to an arid environment?
Creates humid microclimate
51
Why is having sunked or protected stomata an arid environmental adaptation?
Creates humid microclimate within pit through high water vapour retention
52
Why is reduced leaf SA helpful?
Less area for water loss
53
Why is leaf orientation away from the sun helpful?
Less time exposed to hot summer sun
54
WHy is a thick waxy cuticle helpful?
Barrier to evaporation. Shiny surface reflects heat
55
Why is an extensive underground root system helpful?
If deep, tap into groundwater
If shallow/wide, access water as soon as it falls
56
What are epicormic buds?
Structures that lie dormant under the dark until certain events cause them to grow
57
Why are epicormic buds an adaptation?
Can regrow and sprout after fire
58
What are lignotubers?
Swelling at base of a stem/trunk that allows resource storage and regeneration
59
Why do acacias ahve hard outer seed coats?
Acts as protection and remain viable until water is available
60
What are some animal adaptations to an arid environment?
Large SA:V ratio, hump, long intestine, skin that absorbs rain and dew, grooves in skin direct water to mouth, thick fur on the top of the body to provide shade, large and flat feet well-suited for walking on the sand, network of capillaires
61
Why is a large SA:V ratio a good animal structural adaptation?
increase heat loss
62
Why is a hump a good animal structural adaptation?
Store scarce food as fat without insulating the body
63
Why is a long intestine a good animal structural adaptation?
Greater water absorption
64
Why is thick fur on the top of the body (shade) and thin fur on the bottom of the body (heat loss) good?
Shade and heat loss
65
Why are large flat feet good for arid environments?
Walk on sand
66
Why is a rich network of capillaries in mouth and nose good?
Effective heat exchange and oxygen extraction
67
What are some animals adaptations to an artic enviroment?
Thick layer of fur/blubber, small SA:V, greasy coat
68
What is the benefit of a greasy coat in an artic environment?
sheds water after swimming
69
What is the benefit of blubber in an artic environment?
insulation
70
What is the benefit of a small SA:V ratio for animals in an artic environment?
less heat loss
71
What is the benefit of large feet for animals in an artic environment?
spread the load onto ice
72
What is a halophyte?
Plant tolerant to salt
73
What adaptations do halophytes have?
Increasing water uptake to balance salt; excreting excess salt out of glands; shedding leaves with high salt levels
74
What is a tropism?
Directional growth in response to a stimuli. Controlled by hormones
75
What is a positive tropism?
Growth towards stimuli
75
What is a negative tropism?
Growth away from stimuli
75
What is geotropism?
Growth in response to gravity
75
What is phototropism?
Growth in response to light
76
What is chemotropism?
Growth in response to chemicals
77
What is thigmotropism?
Growth in response to touch
78
What is hydrotropism?
Growth in response to water
79
What is an example of phototropism?
Sunflowers grow towards the sun, and move in that direction throughout the day.
80
What is an example of geotropism?
Roots of plants grow towards gravitational field, whereas stem grows away from gravitational field.
81
What is an example of chemotropism?
Growth of pollen through stigma to the ovary is due to presence of sugar.
82
What is an example of thigmotropism?
Pea tendrils coil around the object it comes in contact with.
83
What is an example of hydrotropism?
Growth of plant roots towards higher relative humidity levels.
84
What is a nastic movement?
Movement in response to environmental stimulus but independent to the stimulus direction
85
What is photonasty?
movement in response to light
86
What is an example of photonasty?
Opening and closing of flowers
87
What is an example of a thigmonasty?
Venus fly trap
88
What is a thigmonasty?
Movement in response to touch
89
What is a thermonasty?
Movement in response to temperature
90
What is an example of a thermonasty?
Colour changing flowers throughout the day
91
What is counter current arrangement of blood vessels?
Warm blood from heart (in arteries) is cooled by the blood coming from the veins. This means that when the blood reaches the skin, it is always cool so there is minimal loss of heat. This same warm blood warms the insides.
92
What animals have counter current arrangment of blood vessels?
Marine mammals: feet, flippers, tails
93
Why is camoflauge a physiological adaptation?
Allows animals to blend in with certain aspects of their environment and increases an organism's chance of survival by hiding it from predators.
94
Why is bioluminesence a physiological adaptation?
When light is produced as a result of a chemical reaction, it can lure pray, attract attention or frighten enemies
95
What is torpor?
Lowering an organism's metabolic rate to conserve energy
96
When is torpor usually seen?
Difficult conditions such as cold or lack of food
97
What animals exhibit daily torpor?
Small mammals and birds
98
What is hibernation?
Prolonged period of torpor during winter. Body temperature also significantly drops
99
What is aestivation
Summer torpor: survive high temps and scarce water
100
What is a behavioural adaptation for an artic environment?
Huddling together to conserve heat
101
What is migration?
Moving large distances to seek better food or breeding grounds
102
What are behavioural adaptations for an arid enviornment?
Evaporative cooling behaviours such as paw licking or panting
Basking in sun to raise body temperature.
Seeking shade or shelter.
Living in a burrow.
Nocturnal activity.
103
Example of camoflage
Common octopus has specialised colour-changing cells
104
What is an ecosystem?
A system formed by a community of living organisms interacting with one another in a particular place, living with their abiotic factors
105
What is an individual?
Unicellular or multicellular form exhibiting all of the characteristics of life
106
What is a population?
A group of organisms in the same species that exist and interact at the same time
107
What is a community?
Several interaction populations that coinhabit and depend on one another
108
What is a biome?
Area of the planet with a similar cliamte and landscape
109
What is a biosphere?
ALl regions of the earth occupied by living organisms
110
What is a niche?
The role that a species occupies within an ecosystem
111
What does a niche consist of?
Role in ecosystem, tolerance limits, requirements for shelter
112
What occurs when niches overlap?
Interspecies competiton
113
When there is interspecies competition, what occurs?
Evolution by natural selection towards separate niches
114
What happens when there is a large amount of niche overlap?
Competitive exclusion. One dies
115
What is the competitive exclusion principal?
no two species can occupy the same niche in the same habitat at the same time
116
WHat is symbiosis?
Any kind of close and long-term biological interaction between two different biological organisms. Interspecific
117
What is a symbiont?
Organism in symbiosis with another
118
What is mutualism?
Both partners benefit
119
What is obligate mutualism?
Each species can only live in the presence of another. Completely reliant
120
What is facultative mutualism?
Each species benefits but can survive without its partner
121
What is commensalism?
One organims benefits the other is unaffected
122
What is parasitism?
Non-mutual where one benefits and the other is harmed
123
What is amensalism?
Individual species harms another without benefit
124
What is predation?
A predator feeds on its prey
125
What are the physiological plant adaptations for an artic environment?
High concentraton of solutes that lowers the freezing point of water
Production of anti-freeze proteins that reduce the risk of cell damage
Altering cell membrane lipid composition
126
What is a physiological adaptation in animals to gain water?
Greater use of metabolic water, metabolisign fat to produce water
127
What is a physiological adaptation in animals to stop water loss?
reduced number of sweat glands, concentrated urine, almost dry faeces
128
What is a physiological adaptation in animals to gain heat?
metabolic heat by shivering
reducing bloody flow to extremities by vasoconstriction
129
What is a physiological adaptation in animals to lose water?
Evaporative cooling
Increasing blood flow to extremities
Increased body temp during the day
