BIO 200 Lecture Notes - Lecture 7: Metaphase, Polyploid, Trisomy

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scarletotter85

3 Nov 2017

School

University at Buffalo

Department

Biological Sciences

Course

BIO 200

Professor

jessicapoulin

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Document Summary

Allele frequency: population a group of individuals from a single species, genes are all the same but alleles probably differ, allele frequency is simply the number of times an allele occurs in the population. Frequencies are represented as a proportion of the whole: how do allele frequencies change, gene flow movement of alleles from one pop. to another (example: meadow of white flowers, allele frequency is 1. Assortative mating: organisms of similar phenotype mate more often than expected by random chance; tends to increase the frequency of homozygotes in the population. Example: humans tend to mate with similar heights (homozygous forms over heterozygous forms -> variability goes down) Self-fertilization causes no variability inbreeding is the most common form: genetic drift. Bottleneck effect example: penguins on a beach -> a huge tidal wave strikes and most are killed -> penguins who survived -> restart the population -> frequencies are different. Drift is all about sample size: mutation rate is incredibly small.

Related Questions

Random, chance events that change allele frequencies are knownas:

A. Gene flow

B. Genetic drift

C. Natural selection

D. Balancing selection

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Question 21 pts

What type of selection acts to maintain the two extremephenotypic variants in a population?

A. Disruptive selection

B. Directional selection

C. Positive selection

D. Artificial selection

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Question 31 pts

Approximately, how much of our DNA is shared with our closestrelatives, chimpanzees?

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Question 41 pts

The large canines of male baboons are likely the result of________, while the fact that some male baboons are very colorfulis probably the result of _______.

A. Mutation; balancing selection

B. Gene flow; sexual dimorphism

C. Male competition; female choice

D. Mate choice; genetic drift

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Question 51 pts

Negative assortative mating results in an increased frequency ofhomozygous genotypes within a population.

True

False

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Question 61 pts

Genetic evidence suggests that humans and Neandertals neverinterbred.

True

False

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Question 71 pts

The specific variant of the FOXP2 gene associated with languageacquisition in humans is found in both humans and Neandertals.

True

False

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Question 81 pts

Industrial melanism describes the change in moth color from paleto dark after pollution from factories resulted in coating treetrunks with a layer of dark soot. Which statement is trueconcerning industrial melanism?

A. After pollution levels increased, all moths became darkercolored because soot got on their wings

B. The dark moths survived better after pollution levelsincreased because they were not poisoned by the pollutants

C. Individual moths changed their color in response to thepollution

D. Dark moths were present in the population before pollutionlevels increased

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Question 91 pts

Patterns of evolution can be seen above the species level

True

False

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Question 101 pts

Inbreeding is problematic because it increases the probabilitythat offspring inherit two copies of a recessive mutation thatcauses disease.