Chapter 10 - Selection (ch9) Adaptation Amd Taxonomy Flashcards
What is directional selection
When individuals with an extreme type of characteristic are more likely to survive and reproduce when there is a change in environmental conditions eg antibiotic resistance
Explain the example of antibiotic resistance as directional selection
- Parent population is exposed to antibiotic
- Only those with allele for resistance survive and reproduce
- Allele passed on to offspring
- Mean amount of antibiotic resistance changes
Draw a graph representing directional selection
Folder
What is stabilising selection
Where individuals with extreme types of characteristics are less likely to survive and reproduce
Eg birth weight of mammals
Explain the example of birth weight of mammals as stabilising selection
- Very heavy offspring likely to die due to birth complications
- Very light offspring more likely to die by being cold due to high SA:Vol
- Middle range most likely to survive
- Mean remains the same but range reduces
Draw a graph representing stabilising selection
Folder
What is meant by genetic diversity
The number of different alleles of a gene in a population
What is meant by natural selection
Individuals in a population that are best suited to their environment (due to their alleles and therefore phenotypes) are more likely to survive and reproduce, and so pass on their alleles to next generation
What is meant by evolution
The change in allele frequency overtime
Explain the process of evolution
- Variation of alleles exists in a population
- As a result of mutations
- Natural selection occurs
- Changes allele frequency as negative allele mutation will decrease and beneficial will increase
- Over a long period of time (many generations)
What does natural selection result in
Species being better adapted to their environment
What are the 3 types of adaptations
Anatomical
Physiological
Behavioural
How is a species defined
Organisms are the same species if they can breed to produce fertile offspring
What is meant by taxonomy
The study of classification
What is meant by courtship behaviour
Behaviour where an animal attempts to attract a mate
Why does courtship behaviour increase the chance of successful mating
- Recognition if same species
- Stimulate release of gametes
- Recognise opposite sex
- Indicates sexual maturity
What is an example of courtship behaviour
Birds singing or dancing
What is phylogenetic classification
Arranging species into groups based on their evolutionary relatedness
What is a family tree a type of
Hierarchy
What is a hierarchy
A system that puts small groups within big groups, and there is no overlap between groups
What is a level on a hierarchy called
A taxon
What are the 8 taxonomic ranks
Domain Kingdom Phylum Class Order Family Genus Species
Dominant Kinky People Can Often Find Good Sex
How does the binomial naming system work
First word - Genus Starts with capital letter Second word - Species Lower case Both words in italics or underlined
What are the 3 domains
Bacteria (prokaryotes)
Archaea (prokaryotes)
Eukarya
What does phylogenetics do
Tell us the evolutionary relationships of organism
What are the 2 methods that can be used for phylogenetic classification
Genome sequencing
Immunology
What is immunology
- Seeing if same antibodies bind to a different species antigen
- Because DNA > mRNA > Amino Acids > Proteins
- Tertiary structure of protein tells us about sequence of DNA
- If they bind they are more closely related
What is meant by population
All organisms of one species within a habitat
What is meant by a community
The population of all species in a habitat
What is meant by biodiversity
The variety of species in area
What is meant by species richness
The number of different species in an area
What is meant by index of diversity
Describes the relationship between number of species in a community and the number of individuals of each species
What is the formula for index of diversity
d = N x (N-1)/Sum of n x (n-1)
What does d stand for in formula for index of diversity
Index of diversity
What does N stand for in formula for index of diversity
Total number of organisms of all species
What does n stand for in formula for index of diversity
Total number of organisms of each species
List of effects of farming on biodiversity
- Forests cleared
- Hedgerows removed
- Monoculture (fewer species of plants)
- Herbicides and pesticides used
- Fewer food sources for species
- Fewer species of insects
- Fewer habitats and niches
What are examples of conservation
- Encourage farmers not to clear hedgerows, forests etc..
- Protect species by law (hunting)
- Restrict urban development in areas of high biodiversity
Why does it matter if biodiversity is reduced?
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What is the word for comparing genetic diversity within a species
Introspective
What is the word for comparing genetic diversity between species
(Interspecific)
What can be observed to compare genetic diversity within and between species
- DNA sequence
- mRNA
- Amino acids sequence
- Phenotypes
What are ways that diversity/variation can be caused within a species
- Genetic differences eg blood type
- Environmental differences eg nutrition
Why is it crucial to have a large sample size when sampling a population
- So that data is representative of whole population, which is needed for a statistical test
Why should organisms be selected at random when sampling
To avoid bias
What is meant by the standard deviation
The average variation of the data away from the mean
What is genome sequencing
- Comparing the order of the base sequence of genome of different species
- Higher percentage match means the species are more closely related
