Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Biology 11
Evolution
| Question | Answer |
|---|---|
| Darwin's theory of evolution | the idea that novel heritable traits arise in populations and are passed on from generation to generation. Over time, traits help an organism to reproduce in greater numbers to become a SPECIES |
| Natural selection | the mechnism of evolution. Surviving individuals have a variation that gives them an advantage in competition of resources. Organisms with favourable variations survive and reproduce at a greater rate |
| Ideas that support the theory of evolution | Fossils, homologous structures, comparative anatomy, vestigial organs, embyronic development |
| Fossils | Provides a look at the past: relative ages based on position - lower fossils are older. You are able to see changes in organisms over time |
| Homologous structures | similarity in structure between different species indicates that species have evolved from a common ancestor. Ex. human, cat, whale and bat us limbs for different functions yet they are made of the same bones |
| Comparative anatomy | Evolution states that organisms in similar environments will evolve similar structures (even if they are not seemingly related.) |
| Convergent evolution | 2 unrelated species will evolve similar characteristics independent of one another ex. Bird wings and fly's wings |
| Vestigial organs | organs with no apparent function in an organism. organism has evolved in such a way that it doesn' require the organ anymore. |
| Embryonic development | Early stages of development of animals look very similar. |
| 3 types of natural selection | Stabilizing selection, Directional selection, Disruptive selection |
| Stablizing selection | "Average" trait is selected for ex. plants that are too short = no sun. too tall = wind, weather |
| Directional selection | One extreme is selected for ex. giraffes neck |
| Disruptive selection | selection for both extremes "Bimodal curve" |
| Patterns of evolution | Convergent, divergent, co-evolution |
| Convergent evolution | Unrelated species evolving to become more and more alike due to similar environment. ex. north american cactus and African Europhobia tree. |
| Divergent evolution | Process of 2 or more species becoming more and more dissimilar. |
| Co-evolution | Joint change of 2 species in close interaction ex. plants and animals. both organisms have adaptions to make their relationship more fitting. Mutualistic/symbiotic relationship |
| Speciation | The formation of a new species due to natural selection. |
| Species | Closely related organisms capable of mating and producing fertile offspring. |
| Gradual change Model | Gradual accumulation of adaptation in species over time. |
| Punctuated Equilibrium Model | Species remain unchanged for a long time, "punctuated" by short periods of dramatic changes |
| Hardy-Weinberg equilibrium | P=Dominant allele frequency Q=Recessive allele frequency psquared=frequency of homozygous dominant genotype qsquard=frequency of recessive genotype 2pq= frequency of heterozygous genotype |
| Two equations that define the Hardy-Weinberg equilibrium | psquared + 2pq + q squared = 1............. p+q=1 |
Created by:
ybot
Popular Biology sets