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Chapter:18 Population Genetics and Evolution - Coggle Diagram
Chapter:18 Population Genetics and Evolution
Population of Genetics
Genetics of individual groups of one species
abundance of different alleles within a population
gene pool
total number of alleles in all the sex cells
Conversion of one species into one or several species
Darwin's Origin of Species.
survival of fittest
natural selection
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Extremely slow process
Factors affecting the gene pool
Mutation
preexisting allele decrease and new allele increase
significance depends on population size.
Accidents
organisms unable to adapt
For ex: volcanic eruption, continental drift, Fire
Many phenomenas
Artificial Selection
human purposefully change the allele frequency
For Ex: ornamental plants, trees grown for lumbar
animals selectively bred
Naural selection
Survival of the fittest
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Condition 1. must reproduce viable offsprings
Condition 2. Progeny must differ from each other
inherit traits from parents
Speciation
new species evolution due to natural selection
Phyletic Speciation
Divergent Speciation
Reproductively Isolated
Biological Reproductive barrier
biological phenomena that prevents the gene flow
For Ex: difference in shape, color,fragnance for pollinating flowers
Sympatric Speciation
when two groups becomes reproductively isolated
For Ex:
Mimulus lewisii and M. cardenalis
Prezygotic isolation mechanism
no pollination or fertilization
Postzygotic internal isolation
same species becoming two subspecies that cannot interbreed.
hybrid sterility
two population occasionally interbreed
the seed grows to sterile plant
hybrid inviability
Abiological Reproductive Barriers
Physical, non living features
Allopatric Speciation
species id divided into two or more species
Cannot interbred
Adaptive Radiation
species diverges into many species
For Ex: colonization at Galapagos Island
offsprings resemble first founder
Genetic drift
genepool changing rapidly
gene flow
Pollen Transfer
Animal Mediated Pollination
Seed Dispersal
seeds carried by wind, floods and stream flow
Vegetative Propagation
small, mobile pieces that reproduce vegetatively
Factors that are not part of the Natural Selection
increase in nectar production and increased in pollination
selective advantage due to fungus
Multiple Selection Pressure
Multiple external and internal factors
mutation on certain allele is advantageous
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Convergent Evolution
two different species resembling each other
For Ex: Cacti and euphorbias
Evolution and origin of life
Chemosynthesis
Condition on Earth Before the origin of life
Chemicals Present in the Atmosphere
Energy Sources
Time Available for the origin of life
Chemicals Produced Chemosynthetically
Fats, lipids and nitrogen bases
Formation of polymers
requires high concentration of monomers.
aggregation and organization
Metabolism
Energy metabolism and glycolysis
Oxygen
rust
aerobic respiration
oxidizing atmosphere
Presence of life
inorganic compounds to bacterial
Slow and gradual transitions
