The heritable differences among organisms are a result of .a. differences in their DNA;b. mutation;c. differences in alleles;d. A and B are correct;e. A, B, and C are correct

If nucleotides from the DNA of a human were quantified and 30 percent of them contained the base adenine, what percentage of them would contain the base guanine?a. 20 percentb. 30 percentc. 40 percentd. 70 percent

If an allele is recessive and lethal in homozygotes before they reproduce,a. the allele will be removed from the population by natural selection in approximately 1,000 years.b. the allele will likely remain in the population at a low frequency because it cannot be selected against in heterozygotes.c. the fitness of the homozygous recessive genotype is 0.d. both b and c are correct.

In the 1700s and 1800s, royalty in Europe often married their close relatives; furthermore, recessive genetic diseases such as hemophilia showed up much more often among royals than in the general population. Explain the likely connection.

Explain why continuous growth enhances the phenomenon known as phenotypic plasticity.

According to the RNA world model, a ribozyme would replicate by creating a double-stranded RNA intermediate. Would you expect the intermediate to have the same catalytic activity as the original ribozyme? Justify your answer with an explanation.

A new plant species C, which formed from hybridization of species A(2n = 16) with species B(2n = 12), would probably produce gametes with a chromosome number ofa. 12.b. 14.c. 16.d. 28.

Draw a small concept map showing how selection, genetic drift, gene flow, and mutation relate to genetic variation.

The risks faced by small populations include .a. erosion of genetic variability through genetic drift;b. decreased fitness of individuals as a result of inbreeding;c. increased risk of experiencing natural disasters;d. A and B are correct;e. A, B, and C are correct