Mastering Biology Ch. 22

*Natural selection favors individuals that reproduce more than others. -Natural selection occurs in opposition to evolution -Natural selection is a process whereby genes are selected randomly for preservation in the next generation -Natural selection can be used by farmers to generate organisms with desirable traits (Why: because individuals who are better able to survive and reproduce are more likely to be selected for than individuals who don't survive or cannot reproduce

Adaptation

Heritability

*A cow that produces a large quantity of milk (Why: A cow's ability to produce milk is a heritable trait that can be manipulated by artificial selection)

Large hen, large rooster (Why: Large parents should be bred to produce larger offspring)

A & E (Why: This cross would result in an average corn yield of 189.5 bushels/acre and have a medium-high drought resistance, which is the best you can get for both traits

-Variation in population -Heritable variation -Selection -Differential survival or reproduction

Heritable variation exists for traits among individuals in a population. (Why: this is an accurate statement of the first two steps in the sequence of natural selection.)

Individuals experience differential success in their ability to survive or reproduce. (Why: variation in fitness is required for selection to change the characteristics of a population over time. Remember that selection also requires that the variation in fitness be related to a heritable trait. )

No, drug-susceptible cells and drug-resistant cells are equally likely to infect a new host. (Why: a cell's drug susceptibility of resistance does not affect its ability to infect another host, although a cell;s drug resistance would increase that cell's chances to spread in an environment containing antibiotics due to increased survival.)

The drug-resistance trait is an adaptation to the environment in which human hosts are medicated with the antibiotic rifampin. (Why: Bacterial cells have higher fitness when they are drug resistant in the new environment in which people have been medicated with antibiotics.)

The corn borer must have or generate (by mutation) heritable variation in resistance to the toxic protein. The resistant corn borers must survive better or reproduce more than nonresistant corn borers. (Why: if all these conditions are true, then the corn borer might evolve resistance to the toxic protein.)

True (Why: In an environment without antibotics, individual cells probably would not differ in their reproductive rates of their survival. Without the application of the drug (antibiotic), it would be very difficult to analyze any differences-one wouldn't even be able to sort the cells!)