px1

10. The rate of product formation by an enzyme-catalyzed reaction would be increased by A) adding more substrate molecules. B) adding more product molecules. C) reducing the number of enzymes. D) reducing the number of substrate molecules.

a

14. Protein kinase A is a molecule inside our cells that can activate enzymes within the cell. Proteinkinase A does this by adding phosphates to the enzymes. This is which type of modulation? A) covalent modulator B) competitive inhibitor C) inducer D) reversible antagonist E) irreversible agonist

a

15. Cells regulate their level of activity by regulating the amount of proteins in the cell at any given time,so an up-regulation of enzymes would be expected to A) increase the cell's response produced by the reaction catalyzed by the enzyme. B) decrease the level of productivity of chemical reactions that rely on the enzyme. C) have no effect on the rate of reactions catalyzed by the enzyme. D) decrease the rate of reactions catalyzed by the enzyme. E) decrease the level of productivity of chemical reactions that rely on the enzyme and decrease the rate of reactions catalyzed by the enzyme.

a

6. Glycogen is an example of a A) carbohydrate. B) lipid. C) protein. D) nucleotide. E) lipid and protein.

a

2. Which of the following are examples of cations? A) SO42- B) Ca2+ C) HPO42- D) HCO3- E) more than one of the above is a cation

b

3. The alpha-helix (coils) and pleated sheet are examples of the _______________________ structure of a protein. A) primary B) secondary C) tertiary D) quaternary E) pentanary

b

4. If a substance has a pH that is less than 7, it is considered to be___________________ A) neutral. B) acidic. C) alkaline. D) a buffer. E) a salt.

b

7. Which type of bond would be disrupted by changes in free hydrogen ions in solution, thus disrupting the molecule's shape and function? A) disulfide bonds B) hydrogen bonds C) sodium bonds D) covalent bonds E) double bonds

b

1. The term polar is used to describe some molecules that ____________________________ A. are found in colder climates. B. were first discovered in polar bears. C. have at least two distinct ends regarding charge distribution. D. have at least two distinct ends regarding hydrogen placement. E. are always linear in shape.

c

11. The chemical bonding behavior of an atom is directly determined by the A) number of protons. B) number of neutrons. C) number and arrangement of electrons. D) size of the atom. E) mass of the atom.

c

13. Protein specificity is the A) activation of a specific protein that is needed to perform a particular function. B) degree to which a protein is attracted to a ligand. C) ability of a protein to bind a certain ligand or a group of related ligands. D) degree to which a protein-ligand complex initiates a response. E) B and C

c

12. Which type of bond is the result of an unequal charge distribution caused by an unequal attraction for electrons between the atoms of one molecule? A) non polar covalent B) ionic bond C) weak bond D) polar covalent bond

d

8. An energy-transferring compound in cells is a nucleotide known as A) glucose. B) fructose. C) protein. D) adenosine triphosphate. E) deoxyribonucleic acid.

d

9. Each amino acid differs from others in the A) number of central carbon atoms. B) size of the amino group. C) number of carboxyl groups. D) chemical structure of the R group.

d

5. The molecular function and distinctive shapes of large complex biomolecules resultfrom__________________ A) van der Waals forces B) ionic bonds C) hydrogen bonds D) covalent bonds E) All of the choices can contribute.

e