MICROBIO LAB EXAM MODULE 1 to 6

MICROBIO LAB EXAM MODULE 1 to 6 Module 1 1. True or False: A virus is considered a microorganism. False. Viruses are not living and as such are not considered microorganisms. Viruses can, however, be classified as microbes, a more general term that includes microorganisms and viruses. 2. What is the smallest biological unit of life? A cell. 3. At a generalized level, all cells are comprised of what? Macromolecules* *A student may also answer: Proteins, Lipids, Nucleic acids and Polysaccharides but they must answer with all four to be fully correct. 4. How many different types of amino acids are available from which to make proteins? 20 5. Define an essential amino acid. An essential amino acid cannot be produced by the human body and as such must be take in from the environment through alternative sources (i.e) food. 6. What are the two major types of nucleic acids and their roles? There are two major types of nucleic acids: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). Nucleic acids are chemical molecules that carry genetic information within the cell. DNA contains a vast amount of hereditary information and is responsible for the inheritable characteristics of living organisms. RNA is responsible for deciphering the hereditary information in DNA and using it to synthesize proteins. 7. Complete the following DNA strand and indicate how many bonds are formed for each complementary pair: 3’ GGTCATCG 5’ 5’ CC AGC 3’ 3’ GGTCATCG 5’ 5’ CCAGTAGC 3’ There are 2 bonds formed between A and T, and 3 bonds between G and C. 8. The plasma membrane (select all that are true): *A. Restricts movement of materials in and out of the cell B. Is often a triple layer comprised of lipids *C. Prevents essential nutrients from escaping D. Contains hydrophobic tails pointing outward. 9. How many carbon atoms are present in the monosaccharide glucose? 6 The molecular formula of Glucose is C6H12O6 10. True of False: Eukaryotic cells do not have a nucleus. False. Eukaryotic cells do have a nucleus (prokaryotic cells do not). 11. True or False: Prokaryotic cells can be subdivided into Bacteria and Archaea. True 12. Describe the 4 basic bacterial morphologies. Coccus (round/spherical), bacillus (rod), vibrio (curved rod) or spirillum (spiral/corkscrew). 13. True or False: Archaea, a eukaryotic class of microorganisms, are capable of surviving harsh environments. False. Archaea are prokaryotic bacteria capable of surviving harsh environments 14. Which of the following microorganisms are considered to be Eukarya? Select all that apply. *A. Animalia *B. Plantae *C. Fungi *D. Protista. 15. True of False: All multicellular microorganisms classified as Animalia are heterotrophic. True 16. Microorganisms classified as Plantae obtain most of their energy by converting energy into energy. Light (sunlight); chemical (sugars) 17. A defining characteristic of fungi is the presence of chitin in the cell walls. Which of following also contain chitin? Select all that apply. *A. Mushrooms B. Bacteria *C. Yeast *D. Molds. *all contain chitin. 18. True or False: A defining characteristic of Protista is the inability of colonies to form tissue layers. True. 19. Cell walls are found in which of the following (select all that apply): *A. Plants *B. Fungi *C. Bacteria D. Mammalian cells *E. Algae. 20. The function of the ribosome is (select all that apply): *B. Protein synthesis. Ribosomes are located in the cytoplasm of prokaryotic cells and in the ER of eukaryotic cells. 1 Nucleus 2 Lysosome 3 Plasma membrane 4 Golgi apparatus 5 Rough endoplasmic reticulum MODULE 2 EXAM 1. True or False: As movement requires energy, metabolism can be defined as a controlled set of biochemical reactions that occur in only motile organisms in order to maintain life. False. Metabolism occurs in all living organisms, not just those that move. 2. True or False: Enzymes slow down chemical reactions to conserve energy. False. Enzyme catalyze (speed up) chemical reactions. 3. What is a cofactor? And give a general example. A cofactor is a small chemical component that assists an enzyme during the catalysis reactions. A cofactor is usually metal ions. 5. Define anabolism. Anabolism is the process of building up or biosynthesis of macromolecules from small molecular units into much larger complexes. 5. In order to convert proteins into amino acids which metabolic process would be active? Catabolism would be active as proteins are made up of amino acids. Therefore the process described (proteins into amino acids) is the breakdown, or catabolism of protein. 5. Define anabolism. Anabolism is the process of building up or biosynthesis of macromolecules from small molecular units into much larger complexes. 8. In order to convert proteins into amino acids which metabolic process would be active? Catabolism would be active as proteins are made up of amino acids. Therefore the process described (proteins into amino acids) is the breakdown, or catabolism of protein. 9. Describe the energy transfer process relative to both ATP and ADP. ATP has the energy (phosphate group) to donate while ADP can accept energy in the form of a phosphate group. Thus, ATP can be reduced (ATP →ADP + Pi) while ADP can be built into ATP (ADP + Pi →ATP). 10. An organism that derives its energy (generates ATP) from photons of light is called a? Phototrophic microorganism. An organism that derives its energy by removing electrons from elemental sulfur would be classified as a Lithotroph. 11. A reactive intermediate would be present in which phosphorylation process? A. Photophosphorylation *B. Substrate-level phosphorylation C. Oxidative phosphorylation. B. The chemical compound losing the phosphate group is referred to as the phosphorylated reactive intermediate. 12. The catabolism of a single molecule of glucose goes through what 3 distinct transitions? The breakdown of glucose goes through (1) Glycolysis then (2) Fermentation or Respiration and finally through (3) the electron transport chain (ETC). 13. What is the most energetic transition in the catabolism of glucose? The electron transport chain yields 34 ATP while both glycolysis and fermentation (or respiration) each yield only 2 ATP. 14. Identify the reactants of the following chemical equation: Glucose + 2NAD+ → 2 NADH + 2 Pyruvate + 2 ATP. The reactants are to the left of the arrow: Glucose and 2NAD+ 15. The presence of what molecule ‘signals’ to the cell that glycolysis is about to start? Glucose-6-phosphate (G6P) 16. True or False: In the absence of oxygen fermentation produces 2 ATP. False. Fermentation only reduces NADH back to NAD+ 17. How many ATP does the tricarboxylic acid (TCA) cycle produce per pyruvate? *A. 1 ATP. The TCA cycle produces only 1 ATP per pyruvate. 18. True or False. The products of the TCA cycle enter and fuel the electron transport system. True. The high volume production of reduced electron carriers from the TCA cycle is used by the ETC to drive ATP production. 19. In the absence of glucose, which of the following can be used as alternative energy sources? Select all that apply. *A. Lactose B. Nucleic acids *C. Carbohydrates *D. Lipids A, C, D can all be used as alternative energy sources. 20. For the catabolism of proteins and lipids, which of the following enzymes are used? Select all that apply. A. Ligases *B. Proteases C. Transferases *D. Lipases. B and D. Proteases breakdown proteins while lipases breakdown lipids. 21. True or False. The β-oxidation pathway catabolizes the fatty acid chains of lipids. True 22. Describe the relationship between chloroplasts and chlorophyll. Both chloroplasts and chlorophyll are associated with photosynthesis. Chloroplasts are the double membrane- enclosed organelles that contain the photosynthetic pigment chlorophyll.