The fitness of a genotype is higher when it is rare in a population. Which of the following types of selection is most likely operating?

#Question id: 635

#Section 2: General Biology

The enymatic rate constant (kcat/Km) of orotidine 5ʹ-phosphate decarboxylase is 6 x 10⁷ M^-1s^-1 and the nonenzymatic rate constant (kn) is 3 x 10^-16 s^-1.  What is the value of the enzymeʹs catalytic proficiency?

#Question id: 636

#Section 2: General Biology

DNA polymerase contains a lysine residue that is important for binding to DNA. Mutations were found that converted this lysine to either glutamate, glycine, valine, or arginine. Which mutations would be predicted to be the most and least harmful to the ability of the enzyme to bind DNA?

#Question id: 638

#Section 2: General Biology

Match the following class of enzymes with them

#Question id: 639

#Section 2: General Biology

Match the coenzymes in column I enzymes to class of enzymes in column II

#Question id: 640

#Section 2: General Biology

The data in the table above were collected for an enzyme-catalyzed reaction. The Km for this enzyme is approximately

#Question id: 641

#Section 2: General Biology

Which of the following does NOT describe a mechanism that cells use to regulate enzyme activities?

A. Cells control enzyme activity by phosphorylation and dephosphorylation.

B. Cells control enzyme activity by the binding of small molecules.

C. Cells control the rates of diffusion of substrates to enzymes.

D. Cells control the rates of enzyme degradation.

E. Cells control the rates of enzyme synthesis.

F. Cells control the targeting of enzymes to specific organelles.