Table 1
| 1. For what purpose will the kidneys excrete base as bicarbonate ions (HCO3-)? |
| A. |
Reduce H+ ions concentration in the extracellular fluid (ECF) |
| B. |
Raise H+ ions concentration in the extracellular fluid (ECF) |
| C. |
Increase H+ ions excretion |
| D. |
Reabsorb more bicarbonate ions (HCO3-) |
| E. |
Generate new bicarbonate ions (HCO3-) |
Match the amino acid mutation on the beta globin with the corresponding hemoglobinopathy:
Table 2
| 2. ____ Valine replaces glutamic acid |
| 3. ____ Lysine replaces glutamic acid |
| 4. ____ Valine replaces glutamic acid on one chain while lysine replaces glutamic acid on the other chain |
Table 3
| A. |
Hb C |
| B. |
Hb S |
| C. |
Hb SC |
Table 4
| 5. Which of the following statements is the LEAST ACCURATE about DNA polymerase delta? |
| A. |
This enzyme starts adding polynucleotides to the newly synthesized DNA chain after an RNA-DNA primer is formed on both the leading and lagging strands. |
| B. |
This enzyme can synthesize about 200 nucleotides of DNA in the lagging strand before it reaches the RNA primer of the next Okazaki fragment. |
| C. |
This enzymes continuously add polynucleotides to the newly synthesize DNA in the leading strand. |
| D. |
This enzyme is also considered a 3' to 5' exonuclease that proofreads the newly synthesize DNA to detect and repair DNA changes. |
| E. |
This enzyme has the capabilities of an RNA polymerase and completes DNA synthesis at the end of the chromosomes. |
Table 5
| 6. In which DNA strand are Okazaki fragments MOST LIKELY to be found during DNA replication? |
| A. |
Leading |
| B. |
Lagging |
| C. |
Major groove |
| D. |
Minor groove |
| E. |
RNA primer |
Table 6
7. In the picture below, abnormal red blood cells are microcytic and hypochromic. This picture shows the result of a disorder affecting the heme synthesis and the Fe-S centers of the proteins in the electron transport chain. Which of the following disorders is MOST LIKELY to cause this appearance on a peripheral blood smear? |
| A. |
Hypoxia |
| B. |
Cyanide poisoning |
| C. |
Malaria |
| D. |
Iron deficiency |
| E. |
Hemolytic disease of the newborn |
Table 7
| 8. Which of the following statements about oxidative phosphorylation is FALSE? |
| A. |
One full turn of the c subunits of the F0 pore releases a total of twelve protons into the mitochondrial matrix. |
| B. |
Energy from the electrochemical gradient of the electron transport chain and rotation of the asymmetric shaft of the F0 pore alters the shape of binding sites of the F1 headpiece. |
| C. |
One full term of the binding sites in the F1 headpiece releases twelve ATP molecules. |
| D. |
The three binding sites in the F1 headpiece facilitates: binding of ADP + Pi, as well as synthesis and release of ATP. |
| E. |
The body's increased needs for energy during strenuous exercise ties together oxidative phosphorylation to the electron transport chain and the tricarboxylic acid pathways. |
Table 8
| 9. Which of the following statements is LEAST CORRECT about the process of elongation during protein synthesis? |
| A. |
When the P site in the 60S subunit is bound, an aminoacyl-tRNA must have a complimentary and antiparallel anticodon to the next mRNA codon in order to bind the A site in the 60S subunit. |
| B. |
Peptidyltransferase joins the amino acids attached to tRNAs in both the P and A sites of the 60S subunit. |
| C. |
The aminoacyl-tRNA on A site contains the growing polpeptide chain and moves to the P site when the uncharged tRNA on the P site is released. |
| D. |
The process of forming aminoacyl-tRNA complexes, peptide bonds and translocation of the growing protein chain is repeated numerous times until a stop codon is reached. |
| E. |
The growing polypeptide chains forms only primary and secondary structures once outside the tunnel of the 80S ribosome. |
Table 9
| 10. Which of the following molecules is MOST LIKELY to base pair with Uracil in RNA secondary or tertiary structures? |
| A. |
Adenosine |
| B. |
Guanine |
| C. |
Cytosine |
| D. |
Thymine |
| E. |
Uracil |
Table 10
| 11. Which of the following chemicals is LESS LIKELY to cause damage to the central nervous system or cancer by inhibiting alpha-ketoacid dehydrogenase in the tricarboxylic acid pathway? |
| A. |
Mercury |
| B. |
Arsenate (AsO4-3) |
| C. |
Arsenite (AsO3-3) |
| D. |
NADH |
Table 11
| 12. Which of the following statements about the urea cycle is INACCURATE? |
| A. |
The rate of the urea cycle increases as amino acids are degraded. |
| B. |
The first source of the nitrogen for the cycle is in the form of NH4+. |
| C. |
Aspartate provides the second source of nitrogen for the cycle as NH2. |
| D. |
Brain and muscle tissue provides nitrogen in the form of glutamine. |
| E. |
Bacteria produce NH4+, which travels to the liver via the hepatic portal vein. |
