Microbiology Chapter 8

All of the chemical reactions of the cell are called? catabolism. redox reactions. phosphorylation. metabolism. cellular respiration.

The breakdown of peptidoglycan to N-acetylmuramic acid, N-acetylglucosamine and peptides is an example of: anabolism. catabolism. phosphorylation. fermentation. biosynthesis.

3. Enzymes are? broken down in reactions that require energy input. proteins that function as catalysts. electron carrier molecules. not needed for catabolic reactions. All of the choices are correct.

4. Formation of peptide bonds between amino acids to build a polypeptide would be called? anabolism. phosphorylation. fermentation. exergonic. glycolysis.

5. An apoenzyme: is part of a simple enzyme. is also called a coenzyme. contains the active site. is often an inorganic metal ion. is an RNA molecule.

6. A holoenzyme is a combination of a protein and one or more substances called.? substrates. apoenzymes. catalysts. cofactors. None of the choices are correct

Important components of coenzymes are vitamins? metallic ions. active sites. substrates. ribozymes.

8. Enzymes that are produced only when substrate is present are termed: exoenzymes. endoenzymes. constitutive enzymes. induced enzymes. conjugated enzymes.

9. Enzymes that catalyze removing electrons from one substrate and adding electrons to another are called? phosphotransferases. oxidoreductases. decarboxylases. aminotransferases. ligases.

10. When enzyme action stops due to a buildup of end product this control is called? negative feedback. competitive inhibition. enzyme induction. enzyme repression. None of the choices are correct.

11. Most electron carriers are: coenzymes. enzymes. hydrogens. inorganic phosphate. All of the choices are correct.

12. Exergonic reactions include synthesis of large carbohydrates.? only occur in heterotrophs. occur during aerobic cellular respiration. do not occur in anaerobic cellular respiration. occur when ADP binds to inorganic phosphate to form ATP.

13. In the cell, energy released by electrons is often used to phosphorylate: ATP. ADP. pyruvic acid. oxygen. NAD.

14. The most likely place where an exoenzyme participates in a chemical reaction is: mitochondria. within the cell membrane. lysosomes. cytoplasm. outside of the cell.

15. All of the following are exoenzymes except: ATP synthase. streptokinase. penicillinase. collagenase. elastase.

16. All of the following pertain to glycolysis except it occurs without oxygen: ends with formation of pyruvic acid. occurs during fermentation. degrades glucose to CO2 and H2O. involves reduction of NAD.

17. The formation of citric acid from oxaloacetic acid and an acetyl group begins: glycolysis. electron transport system. Krebs cycle. fermentation. oxidative phosphorylation.

18. During aerobic cellular respiration, the final electron acceptor is? pyruvic acid. oxygen. nitrate. cytochrome c. FAD.

19. Which of the following is NOT involved in the step that occurs between glycolysis and the TCA cycle? reduction of NAD decarboxylation of pyruvic acid coenzyme A attaches to an acetyl group dehydrogenation of pyruvic acid pyruvic acid accepts electrons from NADH

20. In bacterial cells, the electron transport system is located in the: cell membrane. mitochondria. chloroplasts. ribosomes. cytoplasm.

21. In which pathway is the most NADH generated? electron transport system Krebs cycle glycolysis alcoholic fermentation mixed acid fermentation

22. The reactions of fermentation function to produce _____ molecules for use in glycolysis. pyruvic acid ATP NAD NADH glucose

During which of the phases of cellular respiration is the majority of ATP formed? electron transport Krebs cycle glycolysis processing of pyruvic acid for the Krebs cycle All phases produce the same number of ATP molecules.

24. In bacterial cells, when glucose is completely oxidized by all the pathways of aerobic cellular respiration, how many ATP are generated? 2 ATP 3 ATP 24 ATP 36 ATP 38 ATP

25. When glucose is broken down by glycolysis during bacterial fermentation, how many ATP are generated? 2 ATP 3 ATP 24 ATP 36 ATP 38 ATP

26. Each NADH that enters the electron transport system gives rise to _____ ATP. 2 3 24 36 38

27. As the electron transport carriers shuttle electrons, they actively pump _____ into the outer membrane compartment setting up a concentration gradient called the proton motive force. ATP phosphate hydrogen ions oxygen NADH

28. Mixed acid fermentation: produces butyric acid. occurs in all bacteria. produces acids plus CO2 and H2 gases. is seen in Streptococcus and Lactobacillus. also produces ethanol.

29. Anaerobic cellular respiration is also called fermentation. only involves glycolysis. does not generate ATP. utilizes an electron transport system. uses the same final electron acceptors as aerobic respiration.

30. Each FADH2 that enters the electron transport system gives rise to _____ ATP. 2 3 24 36 38

31. In anaerobic respiration, all of the following can serve as the final electron acceptor except: oxygen. sulfate. nitrite. None of the choices are correct.

32. Enteric bacteria commonly occupy the human intestine and primarily produce: CO2 and H2 gasses. methane gas. lactic acid. alcohol. butyric acid.

33. The process of alcoholic fermentation produces: alcohol only. alcohol and oxygen. alcohol and carbon dioxide. carbon dioxide and yeast. yeast and oxygen.

34. Fatty acids can be metabolized by entering: glycolysis. the TCA cycle. the electron transport chain. the phosphogluconate pathway. lactic acid fermentation.

35. Enzymes that are regularly found in a cell are termed: exoenzymes. endoenzymes. constitutive enzymes. induced enzymes. conjugated enzymes.

36. When amino acids are deaminated, they can be used as a source of: glucose. fat. vitamins. minerals. carbon.

37. In eukaryotes, glycolysis takes place: in the mitochondria. in the endoplasmic reticulum. in the cell membrane. in the nucleus. in the cytoplasm.

38. In eukaryotes, the Krebs cycle takes place: in the nucleus. in the endoplasmic reticulum. in the cell membrane. in the mitochondria. in the cytoplasm.

39. ATP molecules are catalysts that lower the activation energy needed to initiate a reaction. True False

40. Hydrolysis reactions are catabolic reactions that use water to split the reactant into smaller subunits. True False

41. ATP synthase is a complex enzyme needed for oxidative phosphorylation. True False

42. Only yeast produces alcohol as a fermentation product. True False

43. Facultative anaerobes can utilize aerobic cellular respiration when oxygen is present and fermentation when oxygen is in low supply. True False

44. All aerobic bacterial species have identical electron acceptors in their electron transport systems. True False

45. ATP is composed of deoxyribose, adenine, and 3 phosphate groups. True False

46. Building block molecules for biosynthetic pathways come from the cell's catabolic pathways and from the environment. True False