BI111 Chapter Notes - Chapter 70: Allele Frequency, Reproductive Isolation, Genetic Divergence

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orangeelk335

23 Jan 2017

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Document Summary

Species: group of organisms that are similar to each other but different from other groups of organisms. Populations: organisms of a single species living in a defined geographic area. Biological species concept states that organisms are members of the same species if they can: interbreed in nature, produce viable and fertile offspring, cannot produce viable and fertile offspring with members of other species. Reproductive isolation: occurs when two organisms from different populations cannot produce viable fertile offspring. Pre-zygotic (before zygote: when organisms cannot reproduce b/c of barriers that prevent them from mating, behavioral barrier. Post-zygotic (after zygote: gametes can unite and form viable zygote, but at any time from post-zygotic cell division to a second generation of hybrids, failure can happen. Donkey-horse mating make infertile offspring: reduced hybrid viability: gametes form a zygote that develops into an organism, but the organisms is too weak to reach reproductive age.

Related Questions

1. The vast majority of animals are:

a. mammals b. invertebrates c. vertebrates d. birds

2. Which of the following scientists defined a species as one or more groups of individuals that can potentially interbreed, produce fertile offspring, and do not interbreed with other groups?

a. Charles Darwin b. Carolus Linnaeus c. Mary Leakey d. Ernst Mayr

3.The earliest primitive primates resembled the modern ___________.

a. tarsier b. tree shrew c. old world monkey d.lemur

4. Stromatolites were formed by:

a. animals b. archaebacterial c. cyanobacteria d. red algae

5. Members of the same species would be expected to:

a.look alike b. be reproductively isolated from one another c. share the same gene pool d.have the same phenotype

6. A species is composed of:

a. related organisms b. a group of reproductive females c. populations that have the potential to interbreed and produce fertile offspring d. organisms located in the same habitat

1. Scientists found that different beak shapes lead to differentmating songs in Darwin's finches. This result best supports whichhypothesis?

	A. Darwin's finches are not different species according to theBiological Species Concept.
	B. Behavioral isolation in Darwin's finches is unrelated to beakshape.
	C. Adaptation to different food sources likely occurred afterreproductive isolation in Darwin's finches.
	D. Adaptation to different food sources indirectly led tobehavioral isolation in Darwin's finches.

2. Which of the following could occur if two partiallyreproductively isolated populations become sympatric? Check allthat apply.

	A. Gene flow between the populations will occur
	B. The populations may eventually become separate speciesthrough reinforcement
	C. The populations will continue to be partially reproductivelyisolated
	D. The populations may eventually lose their geneticdistinctiveness
	E. Hybrids will be inviable or infertile

3. In which population would the rate of genetic drift be thegreatest?

	A large population that is geographically isolated from itsparent population
	A small population that is geographically isolated from itsparent population
	A large population that is not completely geographicallyisolated from its parent population
	A small population that is not completely geographicallyisolated from its parent population

4. Indicate true or false that the following organisms would beconsidered separate species according to the biological speciesconcept. (T/F)

1. Lions and tigers can interbreed successfully to produce viable,fertile offspring, but lions live in open grasslands and tigerslive in dense forests. (T/F)
2. Black bears in the United States can have coat colors rangingfrom blonde to jet black, but bears with different coat colorsoccupy the same habitat and interbreedsuccessfully. (T/F)
3. Many leopard frogs in the eastern United States look the sameand can mate to produce a fertilized egg, but the embryo does notdevelop past the early stages. (T/F)
4. Many of Darwin