U4 AOS2 Flashcards
(68 cards)
1
Q
Allele Frequency
A
The proportion of certain alleles in the gene pool
2
Q
Genotype
A
The genetic composition of an organism at a particular gene locus
3
Q
Population
A
Members of one interbreeding species living in one region at a certain time
4
Q
Gene pool
A
Total genetic info of a population
5
Q
Genotype
A
Total set of genetic info
6
Q
Polygenetic
A
Controlled by multiple genes
7
Q
Monogenentic
A
Controlled by 1 gene
8
Q
Allele Frequency
A
2(#of homo) + Humber of hetero
÷ total #
9
Q
Selective pressures
A
A random event that alters a populations gene pool
10
Q
Natural selection
A
Changes in allele frequencies due to the influence of selection pressures
11
Q
Genetic drift
A
Fluctations in the frequency of alleles in a population as a result of random events
12
Q
Heterozygous
A
Aa
13
Q
Homologous Dominant
A
AA
14
Q
Homologous Recessive
A
aa
15
Q
Bottleneck Effect
A
reduction of genetic diversity in a population due to a random event - natural disaster.
Survivors live by chance
16
Q
Founder Effect
A
reduction of genetic diversity in a population due to a small group of individuals from a larger population moving and making a new popualtion
17
Q
Gene Flow
A
the flow of alleles in and out of a population
18
Q
Immigration
A
movement into a population to increase genetic diversity
19
Q
Emigration
A
movement out of a population to decrease genetic diversity
20
Q
Interbreeding
A
2 individuals from different populations breed and have healthy and fertile offspring
21
Q
Three factors that cause mutations
A
Mutagens (physical and chemical) and pathogens
22
Q
Mutagen
A
an agent that causes mutations in the DNA
23
Q
When is a mutation heritable
A
in the germline cells
24
Q
When is a mutation NOT heritable
A
in the somatic cells
25
Somatic mutations
Mutations that occur in body cells and are not heritable by offspring
26
Germline mutations
Mutations that occur in gametes and are thus heritable by offspring
27
Point mutation
Smallest gene mutation, where only one base is affected, being substitutions, insertions or deletions
28
Silent mutation
When a mutation has no effect on the expression of the genetic material because it still codes for the same amino acid
29
Missense Mutation
A mutation that changes the codon, which now codes for a different amino acid
30
Nonsense mutation
A mutation that causes the formation of a premature stop codon
31
Frame shift mutation
A point mutation that alters the sequence of bases following it
32
Aneuploidy
Gain or loss of a single chromosme
33
Polyploidy
When an organism or cell has the wrong number of sets of chromosomes (such as 3 of each chromosome instead of 2 in humans)
34
Divisions of geological time scale from smallest to largest
Epochs, then periods, then eras, then eons
35
What are fossils?
The preserved remains, impressions or traces of organisms
36
Fossil record
The total number of fossils that have been discovered and provide evidence of evolution
37
Index fossils
Fossils of geologically short-lived species that have a limited occurence in the fossil record and are thus useful for relative dating
38
Transitional fossils
A fossil that shows traits from ancestors and descendants. Shows Relationship.
39
Species
A group of individuals that are able to interbreed under natural conditions to form viable and fertile offspring
40
Prezygotic isolation factor examples
**Before Fertilisation occurs; **
Temporal- day active VS night active
Geographic - mountains vs valleys
Behavioural - rituals
Mechanical - different sex organs
41
Post-zygotic isolation factor examples
** After Fertilization occurs;**
Incompatibility of gametes, inviability of zygote and sterility of hybrid
42
Artificial / Selective breeding
When humans deliberately breed individuals with desirable traits in order to produce offspring that possess these desirable traits
43
Homologous structures
Structures found in different species that are similar but have different functions
44
Vestigial structure
A structure that no longer has a purpose in the organism but did in its ancestor
45
Allopatric speciation
(FInches)
When a geographical barrier prevents gene flow between populations, which evolve over time due to different selection pressures and natural selection favouring different traits as offering selective advantages, eventually the populations would not be able to produce fertile or viable offspring and would be different species
46
Sympatric speciation
(Palms)
When speciation occurs without a geographical barrier, and another factor prevents gene flow
47
Antigenic drift
When mutations in a pathogen's nucleic material results in small changes to its antigens
48
Antigenic shift
When multiple strains of a virus combine to form a new strain of the virus with antigens from each of the original strains
49
Classification of humans
Mammals, primates, hominoids, hominins
50
Structural morphology
The study of the similarities and differences between the structures of species to determine relatedness
51
Hominins vs Hominids
Hominins are humans and all ancestors, Homininds are humans, great apes, and ancestors
52
Why can't carbon 14 dating be used to date rocks?
Carbon 14 dating can only be used with organic material
53
Optimal conditions for the formation of fossils
Rapid burial by deposit of sediment layers, low temperature and anaerobic conditions that are not disturbed and are free of decomposers or scavengers
54
How are monoclonal antibodies produced?
- Antigens that the monoclonal antibodies are designed to act on are injected into a mouse.
- This stimulates the production of B plasma cells specific to this antigen.
- These B plasma cells are extracted from the mouse, and fused with a myeloma to form a hybridoma.
- The antibodies produced are extracted and purified.
55
From fossils, what two pieces of evidence could suggest the fossils are from the same species?
There are relatively few differences between different fossils of the same structures and structures appear to fit together for all fossils
56
Why are ancestral domestic and farm animals very different to modern animals?
Selective breeding has resulted in the increased frequency of traits that humans find desirable
57
Trace fossil and an example
Geological records of the activities of an organism rather than the organism itself, such as footprints
58
Cast
A mold that has filled with sediment
59
Mold
An impression of an organism
60
Primate example and hominoid example respectively
Monkey and orangutan
61
How do cave drawings give evidence of cultural evolution?
Passing of information between generations and evidence of complex thought or symbolic representation
62
Why might populations have similar genetic material?
They may have a relatively recent common ancestor or interbreeding/gene flow may occur
63
When is the gene pool altered?
ONLY when a new allele is introduced or an existing allele is lost
64
3 Advantages of bipedalism
Hands are free for manipulating objects such as tools, increased ability to travel long distances to hunt, and greater vision of predators
65
Trends as human ancestors become more similar to modern humans
Bipedalism (involving the centralised position of the foramen magnum,
curvature of the spinal column and more bowl shaped pelvis), larger brain size (cranial capacity), increase in leg-to-arm length ratio and longer feet with more defined arches.
66
Divergent evolution
When species sharing a common ancestor become more distinct due to different selection pressures
67
Convergent evolution
The process whereby distantly related species independently evolve similar traits to adapt to similar selection pressures
68
Speciation
The process by which a species evolves to give rise to at least one new species
