BIO120H1 Study Guide - Final Guide: Population Bottleneck, Hydroponics, Nonmetal

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Published on 31 Dec 2010
School
UTSG
Department
Biology
Course
BIO120H1
CHAPTER 1: Insect Diversity and Adaptation
-Insects (class Insecta, with 29 orders)
oArthropods: animals with jointed legs
oBody: head, thorax, and abdomen
From thorax extend 3 pairs of legs, 1-2 pairs of wings
oVariety of habitats
oMost successful order: beetles
-Adaptation
oThe trait: improves the organisms chances of survival and reproduction
May be physical or behavioural
Eventually spreads through entire population by natural selection
oThe process: through which such traits arise
oMechanism: natural selection
New traits and new combinations of traits arise through
Mutation: genetic errors
Recombination: mixing of genes through sex
Individuals with favourable traits will have higher fitness
Should such trait be heritable, eventually population will have it
Adaptation Viability OR Reproduction Notes
Camouflage Viability
Feeding Viability
Life in WaterViability
Intra-Sexual
Competition
Reproduction
Mate Choice Reproduction
InsectsOrderNotes
ButterfliesLepidopteraComplete metamorphosis
Larvae feed on vegetation, adults on nectar: different
mouthparts
Adults reproduce: brightly coloured wings
Predator: birds
NOTE!
Evolution is change
over generations in the
proportion of
individuals with a
certain trait.
NOTE!
Not all traits are adaptations.
Consider the evolutionary history and relationships (phylogeny)
Not all differences between populations are the result of natural selection
Genetic drift and gene flow cause populations to change genetically
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WaterstridersHemipteraHabitat: surface film of pools, streams, oceans
Mate choice: struggles only some males can overcome
Water-repellent hairs on feet
Long, thin legs supporting light body
Tubular sucking mouthparts
Excellent eyesight
Walkingsticks Phasmatodea Climate: tropics
Diet: leaves
Mate choice: longer females preferred
Predators: birds, small mammals
Incomplete metamorphosis
Appearance: camouflage
Leaf InsectsPhasmatodea Incomplete metamorphosis
Madagascar hissing
cockroaches
Blattodea Habitat: forests
Diet: vegetable matter
Intra-sexual competition & mate choice: males have bumps
on dorsal prothorax for defending territory and mating,
females prefer larger
Intra-sexual competition & mate choice: males to intimidate
or court, females prefer louder hisses
Females carry eggs in ootheca
Stag, rhino, and buffalo
beetles
ColeopteraComplete metamorphosis
Habitat: decaying wood
Intra-sexual competition: males have mandibles to fight
other males
Stalk-eyed fliesDipteraComplete metamorphosis
Diet: decomposing vegetable matter
Habitat: exposed root hairs of plants
Giant water bugsHemipteraPrey: fish, tadpoles, crustaceans, insects
Paternal care: male carries eggs around
Praying mantidsMantodea Prey: variety of insects
Sit and wait method
Females carry eggs in ootheca
CHAPTER 2: Introduction to Population Genetics
-Population genetics: how Mendels laws (allele segregation and independent assortment) and other genetic principles
apply to populations
oEssential to evolution: evolution being change in genetic composition of a population
oHardy-Weinberg equation: p² + 2pq + q² for a single locus with two alleles
Predicts genotype frequencies (p², 2pq, q²) from allele frequencies (p, q)
Assumes
Sexual reproduction: each sperm has equal chance of fertilizing each
egg
Large enough population size to be unaffected by random gene
changes
No gene flow
Either no mutations or mutational equilibrium
Random reproduction, independent of genotype
Natural selection not acting on a phenotype
Significant deviation from expected Hardy-Weinberg values is evidence of an agent of evolution at
work
-Case 1: Random mating, no selection
oRandom mating of individuals and random union of gametes
oAccept null hypothesis: no selection so no change in genotype and allele frequencies
-Case 2: Selection
oSickle-cell anemia: AA normal, AS survives, SS dies
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Document Summary

Insects (class insecta, with 29 orders) o o o. From thorax extend 3 pairs of legs, 1-2 pairs of wings: most successful order: beetles. The trait: improves the organism"s chances of survival and reproduction. Eventually spreads through entire population by natural selection. Evolution is change over generations in the proportion of individuals with a certain trait. o o. New traits and new combinations of traits arise through. Individuals with favourable traits will have higher fitness. Should such trait be heritable, eventually population will have it. Not all differences between populations are the result of natural selection. Genetic drift and gene flow cause populations to change genetically. Larvae feed on vegetation, adults on nectar: different mouthparts. Mate choice: struggles only some males can overcome. Intra-sexual competition & mate choice: males have bumps on dorsal prothorax for defending territory and mating, females prefer larger. Intra-sexual competition & mate choice: males to intimidate or court, females prefer louder hisses.