Biology Quiz Paper

| | The most important source of nitrogen entering the body is from: | | | Student Response | Value | Correct Answer | Feedback | A. | nucleic acids. | | | | B. | amino acids contained in dietary protein. | 100% | | | C. | urea. | | | | D. | ammonia. | | | | | Score: | 0.1/0.1 | | | 2. | Quest#2 | | Ammonia is converted to urea in the: | | | Student Response | Value | Correct Answer | Feedback | A. | heart. | | | | B. | brain. | | | | C. | kidney. | | | | D. | liver. | 100% | | | | Score: | 0.1/0.1 | | | 3. | Quest#3 | | Which of the following statements about the urea cycle is CORRECT? | | | Student Response | Value | Correct
Answer | Feedback | A. | Urinary urea is increased by a diet rich in protein. | 100% | | | B. | The two nitrogens that are incorporated into urea enter the cycle as ammonia and alanine. | | | | C. | ATP is required for the reaction in which arginosuccinate is cleaved to form arginine. | | | | D. | Urea is produced directly by the hydrolysis of ornithine. | | | | | Score: | 0.1/0.1 | | | 4. | Quest#4 | | The two nitrogens of urea are derived most directly from: | | | Student Response | Value | Correct Answer | Feedback | A. | ammonia and glutamate. | | | | B. | glutamate and aspartate. | | | | C. | ammonia and aspartate. | 100% | | | D. | ammonia and alanine. | | | | | Score: | 0.1/0.1 | | | 5. | Quest#5 | | In the catabolism of amino acids: | | | Student Response | Value | Correct Answer | Feedback | A.
| the first step involves transamination. | | | | B. | ammonia is formed from glutamate. | | | | C. | deamination results in production of an alpha-ketoacid. | | | | D. | All of the above. | 100% | | | | Score: | 0.1/0.1 | | | 6. | Quest#6 | | Maple syrup urine disease: | | | Student Response | Value | Correct Answer | Feedback | A. | is characterized by metabolic alkalosis. | | | | B. | is caused by a deficiency of branched chain alpha-ketoacid dehydrogenase. | 100% | | | C. | if untreated does not change the IQ of affected individuals. | | | | D. | is a common X-linked dominant disorder. | | | | | Score: | 0.1/0.1 | | | 7. | Quest#7 | | Which of the following enzymes is deficient in humans suffering from phenylketouria (PKU)? | | | Student Response | Value | Correct Answer | Feedback | A. | Cystathionine synthase. | | | | B. | Tyrosinase. | | | | C. | Branched chain alpha-ketoacid dehydrogenase. | | | | D. | Phenylalanine hydroxylase. | 100% | | | | Score: | 0.1/0.1 | |
| 8. | Quest#8 | | Which of the following statements concerning heme is CORRECT? | | | Student Response | Value | Correct Answer | Feedback | A. | Heme synthesis begins with glycine and succinyl CoA. | 100% | | | B. | Heme breakdown occurs in the bone marrow. | | | | C. | Congenital errors of heme metabolism result in phenylketonuria (PKU). | | | | D. | Heme bound to O2 is composed of Fe 3+. | | | | | Score: | 0.1/0.1 | | | 9. | Quest#9 | | Heme degradation: | | | Student Response | Value | Correct Answer | Feedback | A. | leads to the formation of protoporphyrinogen. | | | | B. | is catalyzed by aminolevulinate synthase as the rate limiting step. | | | | C. | is inhibited by lead. | | | | D. | occurs predominantly in macrophages in the spleen and liver. | 100% | | | | Score: | 0.1/0.1 | | | 10. | Quest#10 | | The porphyrias: | | | Student Response | Value | Correct Answer | Feedback | A. | are generally inherited as autosomal recessive disorders. | | | | B. | results in the absence of porphyrins or porphyrin precursors. | | | | C. | are caused by inherited or acquired defects in heme synthesis. | 100% | | | D. | results in decreased excretion of porphyrins or porphyrin precursors in the urine. | | | | | Score: | 0.1/0.1 | | | 11. | Quest#11 | | Aminolevulinate synthase activity: | | | Student Response | Value | Correct Answer | Feedback | A. | requires the coenzyme, biotin. | | | | B. | occurs in the cytoplasm. | | | | C. | catalyzes the rate-limiting reaction in porphyrin biosynthesis. | 100% | | | D. | is strongly inhibited by heavy metal ions such as lead. | | | | | Score: | 0.1/0.1 | | | 12. | Quest#12 | | Purines include: | | | Student Response | Value | Correct Answer | Feedback | A. | cytosine and guanine. | | | | B. | adenine and thymine. | | | | C. | adenine and guanine. | 100% | | | D. | cytosine and thymine. | | | | | Score: | 0.1/0.1 | | | 13. | Quest#13 | | Nucleotides: | | | Student Response | Value | Correct Answer | Feedback | A. | are energy-rich compounds. | | | | B. | are components of DNA. | | | | C. | have a nitrogenous base, a pentose and a phosphate. | | | | D. | All of the above. | 100% | | | | Score: | 0.1/0.1 | | | 14. | Quest#14 | | Uric acid: | | | Student Response | Value | Correct Answer | Feedback | A. | is formed primarily in the brain. | | | | B. | is an amino acid. | | | | C. | is the end product of the catabolism of purines. | 100% | | | D. | is utilized in the synthesis of urea. | | | | | Score: | 0.1/0.1 | | | 15. | Quest#15 | | The rate of DNA synthesis in a culture of cells could be most accurately determined by measuring the incorporation of which of the following radiolabelled compounds? | | | Student Response | Value | Correct Answer | Feedback | A. | Phosphate. | | | | B. | Thymidine. | 100% | | | C. | Guanine. | | | | D. | Adenine. | | | | | Score: | 0.1/0.1 | | |