Exam 3: Carbon and the Molecular Diversity of Life

Enzymes that break down DNA catalyze the hydrolysis of the covalent bonds that join nucleotides together. What would happen to DNA molecules treated with these enzymes?

Research indicates that ibuprofen, a drug used to relieve inflammation and pain, is a mixture of two enantiomers, that is, molecules that

Which of the following polymers contains nitrogen?

Which bonds maintain the primary structure of a protein?

Which of the following statements concerning unsaturated fats is true?

Which of the following classes of biological molecules consist of both small molecules and macromolecular polymers?

Figure 3.6 -Which molecule shown in Figure 3.6 is a thiol?

Figure 3.5 -Which molecule shown in Figure 3.5 contains a carboxyl group?

Which of the following is true of cellulose?

Interactions between the side chains (R groups) in a polypeptide are most important in stabilizing which of the following?

A nutritional supplement developed for athletes is shown to contain only carbon, hydrogen, nitrogen, and oxygen. Based on these data, you may safely conclude that

A scientist suspects that food in an ecosystem may have been contaminated by radioactive nitrogen over a period of several months. Which of the following should be isolated from mammals living in the ecosystem and examined for radioactivity in order to test the hypothesis?

Figure 3.5 -Which molecule shown in Figure 3.5 would have a positive charge in a cell?

A new organism is discovered in the forests of Costa Rica. Scientists there determine that the polypeptide sequence of hemoglobin from the new organism has 72 amino acid differences from humans, 65 differences from a gibbon, 49 differences from a rat, and 5 differences from a frog. These data suggest that the new organism is more closely related to

A disulfide bridge is an example of which type of bond?

Which of the following will dissolve in water?

Normal hemoglobin is a tetramer, consisting of two molecules of β-globin and two molecules of α-globin. In sickle-cell disease, as a result of a single amino acid change, the mutant hemoglobin tetramers associate with each other and assemble into large fibers. Based on this information alone, we can conclude that sickle-cell hemoglobin exhibits

The molecular formula for glucose is C₆H₁₂O₆. What would be the molecular formula for a molecule made by linking three glucose molecules together by dehydration reactions?

Figure 3.9 -The molecule shown in Figure 3.9 is a(n)

Which functional group can act as a base?