FINAL revision Flashcards
(88 cards)
1
Q
Independent Assortment
A
when genes segregate independently from each other
2
Q
Epistasis
A
Genes that modify the phenotypic expression of others
3
Q
Addition Rule
A
mutually exclusive outcomes
“either, or”
4
Q
Multiplication rule
A
outcomes that can occur simultaneously, and the occurance of one has no effect on the likelihood of the other
“yellow and wrinkled”
5
Q
Dominant
A
Trait that can be seen
6
Q
Recessive
A
Trait that can’t be seen
7
Q
Alleles
A
Different forms of a gene
8
Q
Genotype
A
the particular combination of alleles present in an individual
9
Q
Phenotype
A
the expression of the trait as described by the genotype
10
Q
Incomplete Dominance
A
phenotype of heterozygous genotype is intermediate
eg red x white –> white
11
Q
Meiosis I
A
homologous chromosomes separate form each other
12
Q
Meiosis II
A
sister chromatids separate
13
Q
Prophase
A
chromosomes condense
14
Q
Prometaphase
A
spindles attach to kinetochores
15
Q
Metaphase
A
chromosomes/chromatids align in the center
16
Q
Anaphase
A
separation of chromosome/chromatids
17
Q
X-linked genes
A
genes located along the X chromosome
18
Q
Autosomal gene
A
affects males and females the same way
19
Q
y-linked genes
A
genes that are present in the unique region of the Y chromosome
only males affected
20
Q
Frequency of recombination
A
a measure of genetic distance between the genes
max=50%
21
Q
Nondisjunction
A
the failure of a pair of chromosomes to separate during anaphase
22
Q
First Division Nondisjunction
A
2 gametes with extra chromosomes; 2 gametes with missing chromosomes
23
Q
Second Division Nondisjunction
A
2 normal gametes; 1 gamete with extra chromosome; 1 gamete with missing chromosome
24
Q
Unbalanced Translocation
A
only part of a reciprocal translocation is inherited from one of the parents
25
Haplotype
Unique combination of nucleotides
26
Heritability
the proportion of the total variation in the trait that is due to genetic differences
27
Regression toward the Mean
offspring exhibit an average phenotype that is closer to the **population mean** than the phenotype of the parents
- environmental effects
- segregation and recombination break up genes of extreme phenotypes
28
Environmental Risk Factor
a characteristic in a person's surroundings that increases the likelihood of developing a particular disease
29
Complex Traits
quantitative traits, affected by many genes
30
Short Term Carbon Cycle
marine/terrestrial photosynthesis and respiration
- photosynthesis is seasonal --\> higher rates in summer, lower in winter
- follows trend in Northern Hemisphere
31
Long Term Carbon Cycle
Fossil fuels--\> moves carbon from long-term to short-term cycle
32
Fluxes
The rate that carbon moves between reservoirs
33
Gene Pool
all the alleles present in all individuals in a species
34
Intrasexual selection
interactions between same sex
35
Intersexual
interactions between females and males
36
Genetic Drift
the random change in allele frequencies from generation to generation
- if population is small, genetic drift is large
37
Non-random mating
| (effect on phenotype and alleles)
preferential mating according to genotypes
- phenotypes increase/decrease
- allele frequencies don't change
38
Hardy Weinberg Equilibrium
p2 + 2pq + q2 = 1
when evolution doesn't occur, allele and genotype frequencies don't change
39
Hardy Weinberg Equilibrium Conditions
1. No natural selection
2. No migration / immigration
3. No mutations
4. Random mating
5. Sufficiently large population to prevent sampling errors
40
Morphospecies
members of the same species usually look alike/ have similar DNA sequences
41
Ring Species
species with populations that are reproductively but not genetically isolated
42
Types of Reproductive Isolation
**pre-zygotic**
behavioral
gametic
mechanical
temporal/geography
**post-zygotic**
genetic incompatibility
43
Speciation
the development of reproductive isolation between populations
44
Allopatric populations
geographically separated populations
45
Dispersal
when individuals colonise a distant place
46
Vicariance
when a geographical barrier arises within a single population
47
Sympatric Populations
populations in same geographic location
- natural selection must strongly counteract the homogenising effect of gene flow
48
Co-speciation
when 2 groups of organisms speciate in response to each other at the same time
49
Monophyletic
all members share a single common ancestor not shared with any other species
50
Paraphyletic
some, bu not all of the descendants of a common ancestor
(two 'cuts' on the tree)
51
Polyphyletic
groupings that don't include the last common ancestor of all members
52
Synapomorphies
evolutionary innovations that are shared by some members of a group
53
Analogous
similarities due to independent adaptation by different species (as opposed to homologous)
--\> result of convergent evolution
54
Convergent Evolution
the process whereby organisms not closely related (not monophyletic), independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.
55
Sister Groups
groups that are more closely related to each other than either of them is to any other group
56
Ectomycorrhizal Fungi
surround root cells
57
Endomycorrhizal Fungi
penetrates root cells
58
Cephalisation
concentration of nervous system at one end of the body
- bilaterians
- to encounter things in environment
59
Abiotic
organisms tend to be adapted to a specific range of physical conditions
60
Biotic
Interactions with other organisms
61
Interspecific competition
competition for resources between individuals from different species
62
Intraspecific competition
when individuals within a population compete for resources --\> natural selection
63
r-strategists
organisms that produce **large number of offspring** without a lot of parental investment
64
k-strategists
organisms that produce **few offspring** but put in a lot of parental investment
65
Density-Dependent Factors
factors such as resource availability, predation, diseases etc
66
Density-Independent Factors
factors that influence population size without regard for population density eg drought, temperature, flood
67
Survivorshipt
the proportion of individuals from the initial cohort that survive to each successive stage of a life cycle
68
Type I
mortality occurs late in life
69
Type II
mortality is even throughout life
70
Type III
mortality is concentrated early in life
71
Metapopulation
a large population made up of smaller populations linkd by occasional movements of individuals between them
72
Facilitation
indirect interaction between 2 attacking species that benefits them both
73
Keystone Species
pivotal populations that support a community
74
Disturbances
severe physical impacts on habitats have effects on density independent populations
75
Succession
the process of species replacing each other in time
76
Symbiosis
close interactions between species that have evolved over long periods of time --\> increases interdependence
77
Obligate
when one/both sides of a mutualism can't survive without the other
78
Facultative
when one/both participants can survive without the other
--\> reinforced by natural selection into obligate
79
Commensalism
one partner benefits with no apparent effect on the other
80
Fundamental Niche
the full range of climate conditions / food resources that permits the individuals in the species to live
- where species *could* live
81
Realised Niche
the actual range of habitats based on interactions with other species
--\> the space species *actually* occupy
82
Competitive Exclusion
competition between 2 species prevents one from occupying a particular niche
--\> leads to resource partitioning
83
Trophic levels
Tertiary consumer - 4
Secondary consumer - 3
Primary consumer - 2
Primary producer - 1
84
Endemic Species
species found in one place and nowhere else
85
Invasive Species
non-native species that become established in new ecosystems
86
Latitudinal diversity gradient
species diversity highest around equator, declines toward poles
--\> spcies at high latitudes are adapted to a greater range of conditions
87
Movement of air
Hot air rises --\> cools --\> generates rainfall --\> air dries, heads toward poles --\> air cools then falls --\> air warms and moves to equator, bringing moisture with it
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