evolution

What is a population's gene pool

* A population's gene pool is the total of all genes in the population at any one time. * If all members of a population are homozygous for a particular allele, then the allele is fixed in the gene pool.

What is the differnce between divergent and convergent evolution

* Divergent evolution - when one species evolves into two or more species with different characteristics * Convergent evolution - species that are not closely related evolve similar traits

Explain the difference between gradualism and punctuated equilibrium.

* Gradualism - slow steady change in species * Punctuated equilibrium - slow evolution punctuated by short events of rapid evolution

What is the difference between variation and an adaption

*Adaptations are products of evolution by natural selection (always good) *Variations are the raw materials upon which natural selection acts (can be good or bad)

Explain the difference between natural and artificial selection. Also sexual selection.

*differential success in reproduction based on heritable traits results in selected alleles being passed to relatively more offspring (Darwinian inheritance). *artificial selection (selective breeding) is the intentional reproduction of individuals in a population that have desirable traits *sexual selection - one genter is selected over another

Explain the main differences among the following types of isolation: reproductive, behavioral, and geographical

*reproductive= when 2 organisms become so different that they cannot reproduce * Behavioral= different behavior keep the population separate and therefor is different * temporal= mating during different seasons leads to inability to reproduce. * Geographical= when 2 organisms are separated by some geographic object and eventually evolve into organisms so different that they cannot reproduce.

What are the five conditions that must be met for a population to be in Hardy-Weinberg equilibrium? What happens if all these conditions are met? Is it easy to stay at H-W equilibrium? Explain.

1. Large population size -Small populations can have chance fluctuations in allele frequencies (e.g., fire, storm). 2. No migration -Immigrants can change the frequency of an allele by bringing in new alleles to a population. 3. No net mutations -If alleles change from one to another, this will chance the frequency of those alleles 4. Random mating -If certain traits are more desirable, then individuals with those traits will be selected and this will not allow for random mixing of alleles. 5. No natural selection -If some individuals survive and reproduce at a higher rate than others, then their offspring will carry those genes and the frequency will change for the next generation. *Deviation from Hardy-Weinberg equilibrium usually results in evolution

What is the diffence between an allele and gene

A gene is the whole trait but an allele is a version of the trait. Ex. Height is the gene and tall and short are the alleles.

Explain what normal distribution is and the difference among disrupitve and stabalizing selection.illustrations are helpful

Directional- one of the exrems is selected for Disruptive- both extreme are selected for Stabalizing- the middle trait is selected for and all members have

Explain the difference between genetic drift and gene flow

Genetic drift is the shrink in the gene pool (all of the combined alleles for all of the organisms in a population) after a decline in population size, while gene flow is the expansion of the gene pool after a growth in populations size. Basically with genetic drift you lose genes and genetic variation while in gene flow you gain it.

Explain the difference between marcoevolution and microevolution

Macroevolution= large scale (the world) Microevolution= small scale (one small area)

Are mutations a good or bad thing? Support your answer

Mutations can be both good and bad. Our skin color was a mutation, a good one, however some can be bad like cystic fibrosis.

What is the bottelneck effect? Name a modern species facing genetic issues due to the bottleneck effect

The bottleneck effect is when you have a population that has many of its organisms wiped out by some sort of natural or man-made disaster. For example, if you look at the population of tuna prior to overfishing, you will see that it was fairly large. However, after the tuna fish were over fished, their population decreased. I think that this could basically be applied to any animal endangered by over hunting. An example of the bottleneck effect based on a natural disaster could be the extinction of dinosaurs. If you hold up a soda bottle upside down, you can see that it has a large base that tapers in and eventually becomes smaller.