Disruptive selection, where there is selection against hybrids, can genetically split a population in the same geographic location into two or more species.  This process of speciation is called:

The __________ period is often called the Age of Amphibians due to the diversification and dominance of that group during this time, but it was also when the plants that formed most of the known major coal deposits lived.

Refer to the representation of DNA replication above.  The structure labeled “D” is:

The rate of cystic fibrosis among Caucasian-American births is about 1 in 2,500.  If the Caucasian-American population is in genetic equilibrium (Hardy-Weinberg equilibrium) for the gene involved in cystic fibrosis, then the frequency of Caucasian-Americans who are carriers (heterozygous) for cystic fibrosis is approximately:

The main source of molecular oxygen (O2) in Earth’s atmosphere is:

The atomic mass of the atom depicted in the above figure is ___ .

Is often applied to subsidiaries in order to allow plaintiffs to reach parent corporations. 

In peas, the allele for tall (T) is dominant over short (t), and the unlinked gene for seed color has the allele for yellow seeds (G) dominant over green seeds (g).  What is the predicted phenotypic ratio for offspring from this cross: ttgg x TtGg

How would you make the distinction between oppositional defiant disorder and conduct disorder?

Alzheimer’s disease and neurocognitive disorder is essentially the same thing.