Name # Class Regents Review: Characteristics of Life and Biochemistry 6. Some processes that occur in a cell are listed below. A. utilize energy B. detect changes in the environment C. rearrange and synthesize chemical compounds Which processes will all living organisms use to maintain homeostasis? 1. Which life process is shown in the image above? A) Respiration B) Transport C) Circulation D) Nutrition 2. An iodine test of a tomato plant leaf revealed that starch was present at 5:00 p.m. on a sunny afternoon in July. When a similar leaf from the same tomato plant was tested with iodine at 6:00 a.m. the next morning, the test indicated that less starch was present. This reduction in starch content most likely occurred because starch was A) changed directly into proteins B) transported out of the leaves through the guard cells C) transported downward toward the roots through tubes D) changed into simple sugars 3. Which term is defined as all the chemical reactions that are required to sustain life? A) metabolism B) nutrition C) regulation D) synthesis 4. Which statement best describes why pathogens are harmful? A) All of the cells of an organism infected by pathogens become pathogens. B) Pathogens cannot be controlled once they enter the cells of an organism. C) Pathogens produce antibodies that will kill the host organism. D) Pathogens can interfere with normal life functions. 5. The failure of the human body to effectively maintain dynamic equilibrium can result in A) reproductive success B) gene manipulation C) differentiation D) disease A) A and B, only B) B and C, only C) C and A, only D) A, B, and C 7. Which life activity is not required for the survival of an individual organism A) nutrition B) respiration C) reproduction D) synthesis 8. Many scientists consider viruses nonliving. Evidence supporting this consideration includes the fact that viruses A) always function independently of living organisms B) are multinucleated cells C) lack basic cellular organelles D) cannot be reproduced in a sterile culture medium 9. The cell theory states that A) all cells have nuclei that contain genetic information B) living organisms are composed of cells that arise from preexisting cells C) all cells regenerate and contain the same basic structures D) organisms that lack certain organelles reproduce by binary fission 10. Which structure is best observed using a compound light microscope? A) a cell B) a virus C) a DNA sequence D) the inner surface of a mitochondrion 11. During an experiment you want to view the nucleus of a cell. How would you most easily view this organelle? A) With a microscope B) With the naked eye C) Using a magnifying glass D) You could not see the nucleus with any of this instruments 12. The invention of the compound light microscope enabled scientists to observe cells, helping them to A) determine the number of atoms in a molecule B) discover a basic similarity among organisms C) study the behavior of chordates D) develop techniques for growing plants in a laboratory
13. Which substances dissolved in the cytoplasm of an ameba enable it to carry on life-sustaining activities? A) inorganic compounds, only B) organic compounds, only C) both inorganic and organic compounds D) neither inorganic nor organic compounds 14. Which substance is an inorganic compound? A) water B) glucose C) maltase D) insulin 15. Which substances are inorganic compounds? A) water and salts B) proteins and carbohydrates C) fats and oils D) enzymes and hormones 16. Which substance plays a major role in most of the chemical reactions that occur in a living cell? A) water B) glycogen C) glycerol D) maltose 17. Which chemical compound makes up the greatest percentage of a protozoan? A) nucleic acid B) glucose C) fatty acid D) water 18. In a living cell, which compound serves primarily as a substance in which most molecules and ions are dissolved? A) glycerol B) glucose C) water D) cellulose 19. Which class of molecules is responsible for speeding up chemical reactions? A) Sugars B) Fats C) Genetic material D) Enzymes 20. Which statement best describes enzymes? A) Every enzyme controls many different reactions. B) The rate of activity of an enzyme might change as ph changes. C) Temperature changes do not affect enzymes. D) Enzymes are produced from the building blocks of carbohydrates. 21. What happens to certain nutrient molecules after they pass into muscle cells? A) They are replicated in the nucleus. B) They are acted on by enzymes and release the energy they contain. C) They are changed into tissues and organs in the cytoplasm. D) They enter chloroplasts, where they can absorb light energy. 22. Base your answer to the following question on the information below and on your knowledge of biology. Organisms living in a bog environment must be able to tolerate nitrogen-poor, acidic conditions. Bog plants such as the Venus flytrap and sundew are able to obtain their nitrogen by attracting and consuming insects. These plants produce chemicals that break down the insects into usable compounds. The chemicals present in the plants that break down the insects are most likely A) fats B) hormones C) enzymes D) carbohydrates 23. Luciferin is a molecule that, when broken down in fireflies, produces heat and light. The rate at which luciferin is broken down in cells is controlled by A) a carbohydrate B) a simple sugar C) an enzyme D) a complex fat 24. Which statement explains the importance of maintaining a constant internal environment to ensure proper enzyme functioning? A) Changes in ph and temperature will cause the enzyme reaction rate to be too fast. B) Temperature and ph determine amino acid sequences in enzymes. C) Changes in ph will change the genetic instructions of enzymes. D) Increasing the temperature and ph can alter the specific shape of enzymes. 25. As temperature increases, the rate of a reaction will A) Decrease B) Remain the same C) Increase D) You can not determine the effect of increasing temperature on the rate of the reaction. 26. A characteristic shared by all enzymes, hormones, and antibodies is that their function is determined by the A) shape of their molecules B) DNA they contain C) inorganic molecules they contain D) organelles present in their structure 27. The function of a specific enzyme is most directly influenced by its A) molecular size B) physical shape C) carrying capacity D) stored energy 28. Glucose molecules are the building blocks of what class of macromolecule? A) Proteins B) Lipids C) Nucleotides D) Carbohydrates
29. Base your answer to the following question on the information and graph below and on your knowledge of biology. The ph of the internal environment of lysosomes (organelles that contain digestive enzymes) is approximately 4.5, while the ph of the surrounding cytoplasm is approximately 7. The average ph of the human stomach during digestion is approximately 2.5, while the average ph of the small intestine during digestion is about 8. The graph below shows how ph affects the enzyme activity of four different enzymes, A, B, C, and D. Which enzyme functions best in a ph environment most similar to that of human stomach enzymes? A) A B) B C) C D) D 30. The enzyme amylase will affect the breakdown of carbohydrates, but it will not affect the breakdown of proteins. The ability of an enzyme molecule to interact with specific molecules is most directly determined by the A) shapes of the molecules involved B) number of molecules involved C) sequence of bases present in ATP D) amount of glucose present in the cell 31. In plants, simple sugars are least likely to be A) linked together to form proteins B) broken down into carbon dioxide and water C) used as a source of energy D) stored in the form of starch molecules 32. Which concept is illustrated by the reaction shown in the diagram below? A) protein hydrolysis B) enzyme specificity C) active transport D) polypeptide ingestion 33. Butter and oil are examples of food composed of A) carbohydrates B) lipids C) proteins D) nucleotides 34. Enzymes are a type of A) Carbohydrate B) Protein C) Nucleotide D) Fatty acid
35. Base your answer to the following question on the diagram below, which represents a chemical reaction that occurs in the human body, and on your knowledge of biology. Substances X and Y are examples of which kind of molecule? A) simple sugar B) amino acid C) fat D) hormone 36. The graph below shows the results of an action of the enzyme catalase on a piece of meat. Evidence of enzyme activity is indicated by bubbles of oxygen. 39. Base your answer to the following question on the information in the diagram below and on your knowledge of biology. Which statement best summarizes the activity of catalase shown in the graph? A) The enzyme works better at 10 C than at 50 C. B) The enzyme works better at 5 C than at 65 C. C) The enzyme works better at 35 C than at either temperature extreme. D) The enzyme works at the same level in all environments. 37. What are the building blocks of lipids? A) Glucose B) Amino acids C) Fatty acids and glycerol D) Nucleic acids 38. The way a protein molecule is folded determines the shape of the molecule, which determines the A) function of that protein B) structure of ATP containing that protein C) type of simple sugars in that protein D) amino acids in that protein In an autotrophic organism, substance B functions as a A) source of energy B) hormone C) vitamin D) biotic resource 40. Base your answer to the following question on the two chemical reactions shown below. Substance C is most likely A) lipase B) sucrase C) maltase D) amylase 41. What are the main atoms of a protein molecule? A) Carbon, hydrogen, nitrogen, and oxygen B) Nitrogen, oxygen, and phosphorous C) Oxygen, sulfur, and nitrogen D) Carbon, phosphorous, and hydrogen
42. Base your answer to the following question on the diagram below, which represents stages in the digestion of a starch, and on your knowledge of biology. The products would most likely contain A) simple sugars B) fats C) amino acids D) minerals 43. Amino acids are the building blocks of which class of macromolecules? A) Proteins B) Lipids C) Carbohydrates D) Nucleotides 44. The shape of a protein is originally determined by the A) size of the protein molecule B) location of the protein within the cell C) arrangement of amino acids in the protein D) function the protein must carry out 45. The diagram below represents a process that occurs in organisms. Which row in the chart indicates what A and B in the boxes could represent? A) 1 B) 2 C) 3 D) 4
Base your answers to questions 46 and 47 on the information below and on your knowledge of biology. Where is the Beef? Out Being Irradiated E. coli bacteria in food cause an estimated 73,000 cases of infection leading to some deaths in the United States each year. Until recently, the only way to guarantee meat free of E. coli was to heat it to 160 F, which kills E. coli. The rare hamburgers preferred by many people are not heated to this temperature, and just a few E. coli may cause severe illness. Recently, ground beef has been decontaminated by irradiation using electron beam technology. The packaged ground beef is scanned by an electron beam that disrupts the genetic structure of the pathogens. This kills them or leaves them unable to reproduce. This process is considered safe and has been endorsed by various governmental groups in this country as well as the World Health Organization. Irradiation is effective in preserving only certain foods, such as herbs, wheat flour, fresh fruits, vegetables, and some meats. Although some methods of irradiation can change the taste of some foods, this is not an effect of electron beam technology on ground beef. Opponents of irradiating food are concerned that the process may result in the formation of chemicals that may be harmful or result in a loss of vitamins. Supporters claim that irradiation is safe and should be considered as just another technique for preservation of food. 46. Explain how irradiation could interfere with the process of reproduction in bacteria that survive the irradiation. 47. Identify the specific group of molecules in bacteria whose function would be interfered with by heating them to 160 F. 48. Base your answer to the following question on the information below and on your knowledge of biology. The graph below shows the effect of substrate concentration on the action of enzyme X. This enzyme is functioning at its optimal temperature, 36 C, and at its optimal ph, 5.5. State what would most likely happen to the rate of enzyme action if the temperature were reduced by 10 degrees. Support your answer. Base your answers to questions 49 and 50 on the diagram below and on your knowledge of biology. 49. If the sequence of building blocks were changed, what effect could it most likely have on the protein?
50. Identify the type of building block represented by the letters A, B, and C.
Answer Key Characteristics of Life and Biochemistry Regents Prep 1. D 2. D 3. A 4. D 5. D 6. D 7. C 8. C 9. B 10. A 11. A 12. B 13. C 14. A 15. A 16. A 17. D 18. C 19. D 20. B 21. B 22. C 23. C 24. D 25. C 26. A 27. B 28. D 29. A 30. A 31. A 32. B 33. B 34. B 35. A 36. C 37. C 38. A 39. A 40. A 41. A 42. A 43. A 44. C 45. C 46. Acceptable responses include, but are not limited to: It causes mutations. Essential enzymes are destroyed. Irradiation disrupts the structure of bacterial DNA so that it cannot replicate properly. 47. Acceptable responses include, but are not limited to: enzymes proteins 48. The reaction will slow down because it is below the optimal temperature. 49. The shape of the protein could change. The function of the protein could be different. It might form a different protein. 50. amino acids or peptides