Bio Homework
By: Steve • Essay • 624 Words • April 7, 2010 • 1,098 Views
Bio Homework
natural selection-the process whereby organisms with favorable variations survive and produce more offspring then less well adapted organisms
variation-the characteristics in individuals that differ from the typical characteristics of other individuals of the same species
adaptation- any kind of inherited trait that improves the chances of survival.
speciation-the formation of a new species.
gradualism- Darwin's theory of evolution, in which new species arise through gradual changes in their characteristics, and thus evolution occurs very slowly over millions of years
punctuated equilibrium- a theory of evolution stating that a species remains the same for a long time then evolves rapidly during a short period of time.
1. the law of use and disuse, The inheritance of acquired characteristics
2. natural selection-the process whereby organisms with favorable variations survive and produce more offspring then less well adapted organisms
3. over production, competition, variation, adaptation
, natural selection, speciation.
accordingly the species remains the same or changes, nothing in between.
modern theory of evolution- according to this theory evolutions happen to populations not individuals
population- a group of organisms of the same species living together in a given region and capable of interbreeding.
population genetics- the genetic make up of populations
gene pool- the total of all the alleles present in a population
genetic recombination- the formation of new combinations of alleles during sexual reproduction.
genetic drift-another factor that affects small populations.
genetic equilibrium- the condition in which allele frequencies do not change from one generation to the next.
1.Mutations, genetic recombination, migration, genetic drift.
2. population- a group of organisms of the same species living together in a given region and capable of interbreeding.
3.gene pool- the total of all the alleles present in a population
4.- the population must be large.
-individuals must not migrate into or out of the population
-mutations must not occur because mutations obviously change the frequencies of the population.
- reproduction must be completely random.
camouflage- an adaptation that provides protection
warning coloration- the colors of the animals actually make it easier to see this is an advantage for certain insects that birds and other enemies find unpleasant to eat.
mimicry-one organism is protected from it's enemies by it's resemblance to another species
directional selection- one type of natural selection , in which an extreme phenotype becomes favorable adaptation
stabilizing