Chapter 3: Structure and Function of the Cell

Chapter 3: Structure and Function of the Cell Multiple Choice 1. The structural and functional unit of all living organisms is the A)ribosome. B)cell. C)organ. D)organelle. E)plasma membrane. Answer: b Level: 1 2. Which of the following could be used to study general features of cells? A)a magnifying glass B)scanning electron microscope C)transmission electron microscope D)binoculars E)light microscope Answer: e Level: 1 3. In order to study in detail, the anatomy of internal cell parts, it would be best to use A)x-rays. B)flashlights. C)a transmission electron microscope (TEM). D)tissue cultures. E)a scanning electron microscope (SEM).Answer: c Level: 1 4. The plasma membrane A)separates the nucleus from the rest of the cell. B)is a rigid protein membrane. C)is not permeable. D)has a single layer of phospholipids. E)regulates movement of materials into and out of the cell. Answer: e Level: 1 5. The environment outside the plasma membrane is most appropriately referred to as A)intrac ellular. B)extracellular. C)multicellular. D)centrocellular. E)none of the above. Answer: b Level: 1 6. The fluid-mosaic model of the plasma membrane suggests that A)cholesterol forms the outermost layer of the membrane. B)proteins form a â€Å"liquid† sea in the membrane.C)phospholipids form a single lipid layer in the center of the membrane. D)the membrane is neither rigid nor static in structure. E)proteins are not a part of the membrane. Answer: d Level: 1 7. According to the most current model of the plasma membrane A)cholesterol forms the innermost layer of the membrane B)proteins are free to move about with a double layer of phospholipids C)phospholipids and cholesterol form a single lipid bilayer D)the membrane is a rigid unchanging structure E)the membrane is impermeable to all other molecules. Answer: b Level: 1 8. Which of the following activities is a function of the plasma membrane?A)digestion of unneeded cell organelles B)recognition of bacterial cells by the im mune system C)transport of products from the nucleus to the endoplasmic reticulum D)cell metabolism E)detoxification Answer: b Level: 2 9. Plasma membrane phospholipids A)have polar (charged) tails. B)are arranged in a single layer. C)have tails that face the exterior of the membrane. D)are 95% cholesterol. E)have a hydrophilic head and hydrophobic tails. Answer: e Level: 1 10. Which of the following is correctly matched with its function? A)channel proteins – are part of an intercellular communication system B)marker molecules – are primarily steroidsC)receptor molecules – attach to ligand molecules. D)peripheral proteins – penetrate the lipid bilayer from one surface to the other. E)nongated ion channels – are always closed. Answer: c Level: 1 11. In general, water-soluble molecules diffuse through the ______ ______; and lipid-soluble molecules diffuse through the ______ ______. A)protein channels; protein channels B)protein channels; bilipid lay er C)bilipid layer; protein channels D)bilipid layer; bilipid layer E)none of the above Answer: b Level: 2 12. Cell membrane phospholipids A)have nonpolar fatty acid tails. B)form a bilayer. C)have polar phosphate heads.D)create a selectively permeable barrier. E)all of the above Answer: e Level: 1 13. When a sperm cell comes into contact with an egg cell, there is a change in the electrical charge across the plasma membrane and various channel proteins close. These channels would be called A)open-gated channels. B)voltage-gated channels. C)chemical-gated channels. D)ligand-gated channels. E)nongated ion channels. Answer: b Level: 2 14. Communication between cells occurs when chemical messengers from one cell bind to _____ on another cell. A)channel proteins B)receptor molecules C)marker molecules D)second messengersE)integrins. Answer: b Level: 1 15. Channel proteins A)are binding sites for other molecules. B)utilize the G protein complex to function. C)are found only on endoplasmi c reticulum. D)allow cells to recognize one another. E)provide a â€Å"door† through which extracellular molecules can enter the cell Answer: e Level: 1 16. Molecules that serve as chemical signals in cell to cell communication are called A)isotopes. B)ligands. C)responders. D)communicators. E)membrane potentials. Answer: b Level: 1 17. Cells that respond to ligands A)possess receptor sites for specific ligands. B)generally produce the ligands.C)have lysosomes that destroy the ligands. D)are using electrical signals in cellualar communication. E)are not functional. Answer: a Level: 1 18. Membrane-bound receptors A)are small, lipid soluble molecules. B)have their receptor sites on the outer surface of the plasma membrane. C)can interact with DNA in the nucleus. D)do not exhibit specificity. E)have no effect on the cell. Answer: b Level: 1 19. Consider the following events and choose the one that occurs last. A)Acetylcholine is released from neurons. B)Acetylcholine diffuses ac ross the synapse to the receptor. C)Na+ ion channels in the plasma membrane are opened.D)Acetylcholine binds to membrane-bound receptors on skeletal muscle cells E)Na+ ions diffuse into skeletal muscle cells. Answer: e Level: 2 20. G proteins are found associated with the A)nucleus. B)cytoplasm. C)Golgi body. D)plasma membrane. E)ribosome. Answer: d Level: 1 21. Communication between cells is essential to coordinate the activity of the trillions of cell that make up the human body. Which of the following is (are) directly involved in carrying out communication between cells? A)lipid bilayer of the plasma membrane B)receptor molecules of plasma membrane C)chemical signal molecules released by cells D)mitochondriaE)b and c Answer: e Level: 1 22. The plasma membrane is selectively permeable. This means A)only gases and water can pass through it. B)substances need permission to pass through it. C)only certain substances can pass through it. D)substances need carrier molecules to pass th rough it. E)ATP is always needed to move molecules across the plasma membrane. Answer: c Level: 1 23. Vitamin A, a fat-soluble vitamin, would move across the plasma membrane into the cell A)in vesicles. B)through vitamin membrane channels. C)by dissolving in the lipid bilayer. D)by transport with carrier molecules. E)by active transport. Answer: c Level: 2 24.Which of the following statements concerning membrane transport across the plasma membrane is true? A)Polar molecules are transported more easily than nonpolar molecules. B)Lipid-soluble substances pass through the membrane by dissolving in the lipid bilayer. C)Water cannot move through the membrane. D)Generally, cations pass through the membrane more easily than anions. E)All molecules are moved across by active transport. Answer: b Level: 1 25. The aroma of cookies baking in the kitchen reaches you in the living room. The distribution of this odor throughout the house is an example of A)active transport. B)dialysis. C)osmosis . D)filtration.E)simple diffusion. Answer: e Level: 2 26. In the process of diffusion, net movement of substances is always from a region A)outside the cell to a region inside the cell. B)inside the cell to a region outside the cell. C)of lower concentration to a region of higher concentration. D)of higher concentration to a region of lower concentration. E)none of the above Answer: d Level: 1 27. Which of the following will increase the rate of diffusion? A)an increase in the viscosity of the solvent B)an increase in the temperature C)an increase in the molecular weight of the diffusing particles D)an increase in the distance the molecules have to travelE)all of the above Answer: b Level: 1 28. Salt was added to a beaker of distilled water (the water was not stirred). A sample taken from the bottom of the beaker was found to be 20% salt. At the same time, a sample taken from the top of the beaker was found to be 2% salt. After 24 hours A)the difference in the percentage of salt bet ween the top and bottom samples would increase. B)the percentage of salt in top and bottom samples would be approximately equal. C)the samples would still be 2% and 20% respectively. D)the salt would float to the top. E)none of the above Answer: b Level: 2 29.The movement of oxygen from the alveoli of the lungs into the bloodstream is an example of A)diffusion. B)osmosis. C)active transport. D)bulk transport. E)facilitated diffusion. Answer: a Level: 2 30. Osmosis is the diffusion of _____ across a selectively permeable membrane. A)urea B)oxygen C)water D)sodium E)sugar Answer: c Level: 1 31. Solution A contains 5 grams of sugar per liter while solution B contains 2 grams of sugar per liter. The solutions are separated by a selectively permeable membrane. If the solvent in both solutions is water, predict in which direction most of the water molecules will move.A)move by simple diffusion from solution A to solution B B)move by osmosis from solution B to solution A C)move by active t ransport from solution B to solution A D)move by filtration from solution A to solution B E)there will be no movement of water Answer: b Level: 3 32. The greater the concentration of a solution, the greater A)the tendency for water to diffuse from the solution. B)the osmotic pressure of the solution. C)the number of carrier molecules present. D)the amount of solvent. E)the rate of facilitated diffusion. Answer: b Level: 1 33. A red blood cell that is placed in a hypertonic solution, A)gains water.B)loses water. C)floats. D)ruptures. E)neither gains nor loses water. Answer: b Level: 2 34. If 0. 9% saline solution is isotonic to a cell, then a 0. 5% saline solution A)is hypertonic to the cell. B)will cause crenation of the cell. C)is hypotonic to the cell. D)will shrink the cell. E)will not affect the cell. Answer: c Level: 2 35. A person suffered from burns over a large part of his body. Evaporation of fluid from the surface of burned areas occurs. As a result of the evaporation proc ess, cells will tend to A)shrink. B)swell. C)rupture. D)first swell and then resume their original shape. E)remain unchanged. Answer: aLevel: 2 36. Plasma has an osmolality of 300 mOsm. A solution isosmotic with plasma has an osmolality of A)150 mOsm. B)300 mOsm. C)450 mOsm. D)600 mOsm. E)900 mOsm. Answer: b Level: 2 37. A runner produced hypotonic sweat while running a marathon in hot weather. After the race he drank large volumes of water, as a result of the water intake his body cells will A)shrink. B)swell. C)crenate. D)shrivel. E)not change. Answer: b Level: 2 38. The movement of a solution across a plasma membrane because of a pressure gradient is called A)diffusion. B)osmosis. C)facilitated diffusion. D)active transport. E)filtration. Answer: eLevel: 1 39. Which of the following would increase the rate of mediated transport? A)increase the number of available carrier molecules B)change the shape of the binding site on the carrier molecule C)increase the number of competitive molecules D)fill all binding sites on carrier molecules E)remove the binding site on the carrier molecule Answer: a Level: 2 40. A particular membrane transport process exhibits saturation, uses carrier molecules, but does not require ATP. The process is probably A)active transport. B)facilitated diffusion. C)osmosis. D)pinocytosis. E)phagocytosis. Answer: b Level: 2 41. Active transportA)follows osmotic pressure gradients. B)can move substances along their concentration gradient. C)does not requires metabolic energy (ATP). D)involves vesicle formation. E)requires ATP. Answer: e Level: 1 42. Which of the following are consistent with active transport? 1. movement is against a concentration gradient 2. movement is with a concentration gradient 3. involves a carrier molecule 4. can involve cotransport 5. can involve counter transport 6. exhibits competition and saturation A)1, 3, 4, 5, 6 B)2, 3, 4, 5 C)2, 3, 4, 5, 6 D)1, 3, 4, 6 E)1, 3, 5, 6 Answer: a Level: 2 43. Cyanide stops the pr oduction of ATP.Which of the following processes would be affected? A)simple diffusion B)osmosis C)active transport D)facilitated diffusion E)filtration Answer: c Level: 2 44. The sodium-potassium exchange pump located in the plasma membrane A)actively transports potassium into cells. B)osmotically moves sodium into cells. C)actively transports water out of cells. D)moves chlorine out of cells. E)actively transports sodium into cells. Answer: a Level: 1 45. When ions or molecules involved in secondary active transport move in the same direction, the process is called A)facilitated diffusion. B)counter-transport. C)exocytosis. D)cotransport. E)endocytosis.Answer: d Level: 1 46. Which of the following events occurs in the secondary active transport of glucose? A)Na+ ions and glucose are cotransported by the same carrier molecule. B)The Na+-K+ pump maintains a Na+ concentration gradient inside the cell. C)Energy comes from diffusion of Na+ down their concentration gradient. D)Glucose i s moved against its concentration gradient into the cell. E)all of the above Answer: e Level: 2 47. A group of cells was treated with a proteolytic (protein-digesting) enzyme. Which of the following processes would be least affected by this treatment? A)diffusion of sodium through sodium membrane channelsB)diffusion of lipid-soluble molecules through the plasma membrane C)use of carrier molecules in facilitated diffusion D)sodium-potassium exchange pump E)secondary active transport Answer: b Level: 2 48. Certain cells in the liver ingest bacteria and debris from damaged cells by a process called A)pinocytosis. B)phagocytosis. C)biocytosis. D)calmly regulated diffusion. E)exocytosis. Answer: b Level: 2 49. Pinocytosis A)is a form of exocytosis. B)involves ingestion of liquids rather than particles. C)does not require ATP. D)forms vesicles only when large amounts of material are being transported. E)does not require the formation of vesicles.Answer: b Level: 1 50. Endocytosis A)is mov ement of water through a selectively permeable membrane. B)is a process that requires a carrier molecule but does not use cellular energy. C)is the bulk uptake of material through the plasma membrane by vesicle formation. D)moves material out of the cell. E)ends cell functions. Answer: c Level: 1 51. Arrange the following events of exocytosis in the correct sequence: 1. vesicle membrane fuses with plasma membrane 2. secretory vesicles migrate to plasma membrane 3. vesicle contents are expelled from cell 4. secretions accumulate within secretory vesicles A)2, 1, 4, 3B)1, 4, 2, 3 C)3, 1, 4, 2 D)4, 2, 1, 3 E)1, 2, 3, 4 Answer: d Level: 3 52. Receptor-mediated endocytosis A)does not need ATP; the receptors supply the energy. B)exhibits specificity. C)occurs if oxygen is available. D)is a type of passive transport. E)moves materials out of the cell. Answer: b Level: 1 53. Which of the following are consistent with facilitated diffusion? 1. movement is against a concentration gradient 2. movement is with a concentration gradient 3. involves a carrier molecule 4. involves cotransport 5. involves counter transport 6. exhibits competition and saturation A)1, 2, 4, 5, 6 B)2, 3, 6C)2, 3, 5, 6 D)1, 3, 4, 5, 6 E)2, 3, 4, 6 Answer: b Level: 2 54. Which of the following would increase the maximum rate of facilitated diffusion? A)increase the concentration gradient of the transported molecule B)decrease the concentration gradient of the transported molecule C)increase the concentration of the competitive molecules D)increased ATP synthesis E)none of the above Answer: e Level: 3 55. If a toxic drug inhibited mRNA synthesis, which of the following would be most directly affected? A)protein synthesis B)intracellular digestion C)microtubule production D)secretion of glycoproteins and lipoproteinsE)active transport Answer: a Level: 2 56. Cytoplasm is found A)in the nucleus. B)outside the nucleus but inside the plasma membrane. C)in the cisternae of the endoplasmic reticulum. D)on the cristae of the mitochondria. E)between the phospholipids in the plasma membrane. Answer: b Level: 1 57. The cytoskeleton consists of A)lipochromes, microfilaments, and microtubules. B)actin filaments, mitochondria, and intermediate filaments. C)microfilaments, mitochondria, and lipochromes. D)microtubules, actin filaments, and intermediate filaments. E)ribosomes, the nucleus, and the Golgi apparatus. Answer: d Level: 1 58.Absence of a cytoskeleton might affect A)cell shape. B)the number of channel proteins in the cell membrane. C)the ability of the cell to generate energy. D)vesicle formation. E)membrane transport. Answer: a Level: 1 59. Microtubules A)are the smallest components of the cytoskeleton. B)contains the protein myosin. C)provide structure and support to the cytoplasm. D)are solid, supporting rods of protein. E)are a component of mitochondria. Answer: c Level: 1 60. Of the organelles listed, which one does not contain microtubules? A)cilia B)flagella C)centrioles D)mi crovilli E)basal bodies Answer: d Level: 1 61.Organelles A)are extracellular structures. B)are unspecialized portions of a cell. C)generally lack membranes. D)vary in number and type depending on cell function. E)are structural, but not functional parts of the cell. Answer: d Level: 2 62. Which of the following organelles function in the destruction of nonfunctional organelles? A)endoplasmic reticulum B)centrioles C)basal bodies D)lysosomes E)mitochondria Answer: d Level: 1 63. Ribosomes are organelles responsible for A)protein synthesis. B)manufacturing lipids. C)cell movement and cell shape. D)packaging â€Å"cell products† for export. E)energy production.Answer: a Level: 1 64. Cells that lack ribosomes cannot A)produce energy. B)eliminate wastes. C)engage in protein synthesis. D)package cellular products. E)ingest and phagocytize bacteria. Answer: c Level: 1 65. Skeletal muscle cells need large numbers of _______ to make the many proteins they contain. A)centrosomes B)pero xisomes C)liposomes D)ribosomes E)lysosomes Answer: d Level: 2 66. If you compare a cell with a manufacturing plant that exports goods, the cell's _____ could be compared to the manufacturing plant's shipping department. A)nucleus B)lysosome C)Golgi apparatus D)endoplasmic reticulumE)ribosome Answer: c Level: 2 67. The organelle that protects cells from the damaging effects of medications and toxins is the A)ribosome. B)microtubule. C)secretory vesicle. D)smooth endoplasmic reticulum. E)mitochondria. Answer: d Level: 1 68. The function of the Golgi apparatus is A)packaging and distribution of proteins and lipids. B)production of microtubules. C)excretion of excess salt. D)DNA replication. E)energy production. Answer: a Level: 1 69. Endoplasmic reticulum with ribosomes attached to it is called A)smooth ER. B)dendritic ER. C)nodular ER. D)bumpy ER. E)rough ER. Answer: e Level: 1 70.A cell that produces many proteins for secretion from the cell would have large numbers of A)rough ER an d Golgi. B)lysosomes and Golgi. C)Golgi and microvilli. D)ribosomes and centrioles. E)mitochondria and cilia. Answer: a Level: 2 71. Arrange the following in correct sequence: 1. Protein moves through ER and then carried in vesicles to Golgi. 2. Vesicle pinches off from Golgi and carries product to plasma membrane. 3. Golgi modifies protein and then packages them into vesicles. 4. Protein made by ribosomes on rough ER. A)1, 2, 3, 4 B)4, 1, 3, 2 C)2, 3, 1, 4 D)3, 2, 4, 1 E)4, 3, 2, 1 Answer: b Level: 2 72.A toxic drug destroyed the Golgi apparatus. This would affect A)ribosomal RNA synthesis. B)intracellular digestion. C)energy production. D)microtubule production. E)packaging of glycoproteins and lipoproteins. Answer: e Level: 2 73. The intracellular digestive system of a cell is the A)lysosome. B)microtubule. C)lipochrome. D)rough endoplasmic reticulum. E)smooth endoplasmic reticulum. Answer: a Level: 1 74. White blood cells eat other cells and would be expected to A)have large num bers of lysosomes. B)possess cilia on their surfaces so they can move quickly. C)excrete excess salt as a result of all this eating.D)expel their nuclei to make room for all of the cells they eat. E)have mitochondria to energize them. Answer: a Level: 2 75. Which of the following activities is associated with lysosomes? A)exocytosis B)intracellular support C)destruction of nonfunctional organelles D)energy production E)endocytosis Answer: c Level: 1 76. A cell with abundant peroxisomes would most likely be involved in A)secretion. B)storage of glycogen. C)detoxification activities. D)cellular communication. E)protein synthesis. Answer: c Level: 1 77. Damaged cells can destroy nearby healthy cells when they release ________ enzymes. A)mitochondrialB)nuclear C)microtubular D)lysosomal E)cytoplasmic Answer: d Level: 1 78. A cell's ability to replenish ATP is reduced by a metabolic poison. Which organelle is being affected? A)nucleus B)centriole C)microtubule D)mitochondrion E)ribosomes Answer: d Level: 2 79. Experimental manipulation to increase the energy output of the cell might include A)rupturing the lysosomes in the cell. B)increasing the number of mitochondria. C)decreasing nuclear size. D)removing some of the ribosomes. E)increasing protein synthesis. Answer: b Level: 1 80. Which of the following terms does not relate to the mitochondria? A)cristaeB)self-replicating C)outer and inner membranes D)ATP E)vitamin A storage Answer: e Level: 1 81. When a person trains for running long distances, which of the following organelles increase in his/her muscles? A)rough endoplasmic reticulum B)enzymes for glycolysis C)basal bodies D)lysosomes E)mitochondria Answer: e Level: 2 82. You are looking at a cell with the electron microscope and you notice the following characteristics: presence of many mitochondria and lysosomes; few, if any, Golgi; and many ribosomes. Which of the following is the most likely function of that cell? A)secretion of lipids B)intracellular dig estionC)DNA replication D)modification of protein E)absorption of nutrients Answer: b Level: 2 83. Which of the following pairs of terms is mismatched? A)mitochondria – cristae B)Golgi apparatus – cisternae C)lysosomes – hydrolytic enzymes D)smooth endoplasmic reticulum — chromatin E)cilia – basal bodies Answer: d Level: 1 84. Mitochondria A)contains DNA. B)have inner and outer membranes. C)have inner folds called cristae. D)are the cell’s power plants. E)all of the above Answer: e Level: 1 85. Which of the following cell organelles is correctly matched with its function? A)nucleolus – contains the genetic material of the cellB)microtubules – cell support C)mitochondria – protein synthesis D)smooth ER – ATP production E)ribosome – energy production Answer: b Level: 1 86. A cell can meet increased energy demands by an A)increase in its overall size so it has more room to generate energy. B)increase in the nu mber of mitochondria. C)increase in lysosomal enzyme and ribosome activity within the cell. D)increase in nuclear DNA activity. E)increase in ribosomal subunits. Answer: b Level: 1 87. A cell uses centrioles in the process of A)cell division. B)energy generation. C)protein synthesis. D)RNA replication. E)nuclear centering.Answer: a Level: 1 88. Cilia and flagella are distinguished from each other on the basis of A)width and numbers. B)length and numbers. C)depth and numbers. D)length and width. E)none of the above Answer: b Level: 1 89. Microvilli A)are extensions of the lysosomal membrane. B)function to make the cell mobile. C)are supported by microtubules. D)move the cell. E)increase the surface area of the cell. Answer: e Level: 1 90. Which of the following cell organelles does not contain microtubules? A)cilia B)flagella C)spindle fibers D)centrioles E)All of the above contain microtubules. Answer: e Level: 1 91.The â€Å"control center† of the cell is the A)nucleus. B)ri bosome. C)mitochondrion. D)plasma membrane. E)endoplasmic reticulum. Answer: a Level: 1 92. Which of the following events occurs in the nucleus? A)large and small ribosomal subunits combine B)ribosomal proteins formed C)large and small ribosomal subunits form D)formation of free ribosomes E)None of the above occur in the nucleus. Answer: c Level: 1 93. Which of the following structures is found in the nucleus? A)cristae B)cytosol C)cisternae D)chromosome E)flattened membrane sacs Answer: d Level: 1 94. The nucleus of a cell functions to A)digest lipids.B)produce ATP. C)produce secretory vesicles. D)control and coordinate cellular activities. E)synthesize proteins. Answer: d Level: 1 95. Nucleoli A)are located in the cytoplasm. B)produce ribosomal subunits. C)have a distinct membrane. D)are important for the formation of the Golgi apparatus. E)regulates movement of materials into the nucleus. Answer: b Level: 1 96. Which of the following correctly matches a nuclear structure with its function? A)chromosomes – contains RNA and histones B)nuclear envelope – contains the nucleolar organizer C)nuclear pores – allow molecules to move between the nucleus and cytoplasm.D)chromatin – fluid portion of the nucleus E)nucleolus – DNA synthesis Answer: c Level: 1 97. Glycolysis A)converts glycogen to glucose. B)reduces pyruvic acid to carbon dioxide and water. C)converts glucose to pyruvic acid. D)is oxygen dependent. E)does not occur in the cell. Answer: c Level: 1 98. Aerobic respiration occurs when _______ is available. A)carbon dioxide B)oxygen C)lactic acid D)light E)nitrogen Answer: b Level: 1 99. Anaerobic respiration A)occurs in cells when oxygen supplies do not meet cell demands. B)produces 38 ATP molecules per glucose molecule. C)occurs in the mitochondria.D)frequently involves the electron transport system. E)is referred to as the â€Å"citric acid cycle. † Answer: a Level: 1 100. Messenger RNA A)is synthesized when a por tion of a DNA molecule is transcribed. B)directs the synthesis of DNA. C)determines the sequence of nucleotides in the anticodons of tRNA. D)directs the synthesis of centrioles in the cytoplasm. E)is not involved in the synthesis of proteins. Answer: a Level: 1 101. The transfer of information from DNA to messenger RNA (mRNA) is known as A)transduction. B)translocation. C)translation. D)transcription. E)transmutation. Answer: d Level: 1 102.Which of the following sequences is correct? A)translation ( protein synthesis ( transcription B)transcription ( translation ( protein synthesis C)transcription ( protein synthesis ( translation D)translation ( transcription ( protein synthesis E)protein synthesis ( translation (transcription Answer: b Level: 1 103. Translation A)requires three types of DNA. B)requires the pairing of codons on mRNA with anticodons on tRNA. C)involves synthesis of RNA from DNA molecules. D)takes place in the nucleus. E)requires replication of DNA. Answer: b Level: 1 104. Which of the following molecules contains the anticodon?A)mRNA B)rRNA C)tRNA D)DNA E)none of the above Answer: c Level: 1 105. If a mRNA molecule is 1800 nucleotides (bases) in length, this molecule will contain _____ codons. A)400 B)600 C)800 D)900 E)1200 Answer: b Level: 2 106. The sequence of nucleotides in a messenger RNA molecule is needed to determine the A)sequence of nucleotides in a gene. B)sequence of amino acids in a protein. C)sequence of nucleotides in the anticodons of tRNA. D)sequence of codons in DNA. E)sequence of amino acids in DNA. Answer: b Level: 1 107. Transcription A)requires three types of RNA. B)synthesizes RNA from DNA.C)occurs at the ribosomes. D)copies information from mRNA to tRNA. E)synthesizes DNA from RNA. Answer: b Level: 1 108. A DNA base sequence is A T G C C G. The sequence of bases in a strand of mRNA transcribed from this sequence of bases in DNA would be A)T A C G G C. B)U T C G G U. C)U A C G G C. D)A U G C C G. E)T A G G G G Answer: c Level: 2 109. The anticodon sequence GUA pairs with which of the following codons? A)CAT B)GUA C)CTU D)CAU E)CTT Answer: d Level: 2 110. Posttranscriptional processing is the modification of A)proteins to form pro-proteins. B)mRNA to form tRNA. C)pre-mRNA to form functional mRNA.D)exons to form introns. E)DNA. Answer: c Level: 1 111. Determine the sequence of the following events in a cell after exposure of the cell to a chemical signal. 1. increased synthesis of a protein 2. the chemical signal combined with a cytoplasmic receptor 3. an increase in the nuclear concentration of the chemical 4. an increase in mRNA synthesis 5. genes are activated A)2, 1, 3, 5, 4 B)2, 4, 5, 3, 2 C)2, 3, 5, 4, 1 D)2, 3, 4, 5, 1 E)1, 2, 3, 4, 5 Answer: c Level: 3 112. DNA replication results in two new DNA molecules. Each of these new molecules A)has two newly synthesized strands of nucleotides.B)has one strand of nucleotides from the parent DNA and one newly synthesized strand of nucleotides. C)has tw o strands of nucleotides from the parent. D)has a single strand of nucleotides. E)are incomplete copies of the original. Answer: b Level: 1 113. In DNA replication, A)the leading strand is formed as a continuous strand. B)new nucleotides are added at the 5†² end of the growing DNA strand. C)DNA polymerase splices the short segments of the lagging strand together. D)only introns are replicated. E)the two existing strands are not used as templates. Answer: a Level: 1 114. MitosisA)forms two daughter cells with half the DNA of the mother cell. B)forms two daughter cells with the same amount of DNA as the mother cell. C)forms daughter cells called gametes. D)forms two daughter cells with twice the amount of DNA as the mother cell. E)forms one daughter cell and another incomplete cell. Answer: b Level: 1 115. Human somatic cells contain _____ chromosomes, human gametes contain _____ chromosomes. A)23; 46 B)23; 23 C)46; 46 D)46; 23 E)92; 46 Answer: d Level: 1 116. DNA synthesis occur s during A)the G1 phase of interphase. B)telophase. C)the S phase of interphase. D)anaphase. E)metaphase. Answer: cLevel: 1 117. In prophase A)the chromosomes condense, shorten, and thicken. B)the spindle fibers disappear. C)the chromosomes replicate. D)cytokinesis occurs. E)DNA is synthesized. Answer: a Level: 1 118. Which of the following events occurs during anaphase? A)Chromatin strands condense to form chromosomes. B)Chromosomes migrate to opposite poles of the cell. C)Spindle fibers are formed. D)The nuclear envelope degenerates. E)Cytokinesis Answer: b Level: 1 119. Meiosis is the process of cell division that results in the formation of A)skin cells. B)gametes (egg and sperm). C)diploid cells. D)malignant cells. E)somatic cells.Answer: b Level: 1 120. Arrange the following events of meiosis in correct sequence. 1. pairs of homologous chromosomes separate 2. tetrad formation occurs 3. second meiotic division 4. tetrads align at the equatorial plate 5. interkinesis A)1, 3, 5, 2, 4 B)2, 4, 1, 5, 3 C)3, 1, 4, 5, 2 D)4, 1, 2, 5, 3 E)2, 4, 1, 3, 5 Answer: b Level: 2 121. Each of the cells that result from meiosis A)has the same number of chromosomes as the original cell. B)has half the number of chromosomes as the original cell. C)has one-fourth the number of chromosomes as the original cell. D)has twice the number of chromosomes as the original cell.E)has no chromosomes Answer: b Level: 1 122. Crossing over A)occurs during mitosis. B)increases the amount of genetic diversity. C)results in the formation of chromatids with the same DNA sequences. D)form tetrads. E)decreases the amount of genetic diversity. Answer: b Level: 1 Refer to the following diagram for questions 123-127. [pic] 123. What structure does â€Å"A† represent on the diagram of the plasma membrane? A)membrane channel protein B)phospholipid bilayer C)internal membrane surface D)peripheral protein E)receptor protein Answer: b Level: 1 124. What structure does â€Å"B† represent on the diagram of the plasma membrane?A)membrane channel protein B)phospholipid bilayer C)internal membrane surface D)peripheral protein E)receptor protein Answer: a Level: 1 125. What structure does â€Å"C† represent on the diagram of the plasma membrane? A)membrane channel protein B)phospholipid bilayer C)internal membrane surface D)peripheral protein E)receptor protein Answer: e Level: 1 126. What structure does â€Å"D† represent on the diagram of the plasma membrane? A)membrane channel protein B)phospholipid bilayer C)internal membrane surface D)peripheral protein E)receptor protein Answer: d Level: 1 127. What structure does â€Å"E† represent on the diagram of the plasma membrane?A)membrane channel protein B)phospholipid bilayer C)internal membrane surface D)peripheral protein E)receptor protein Answer: c Level: 1 Refer to the following diagram for questions 128-132. [pic] 128. Red blood cells (RBCs) have been placed in three different solutions: hypotonic , hypertonic, isotonic. What is solution â€Å"A† relative to the RBC? A)hypotonic solution B)hypertonic solution C)isotonic solution D)hemolyzed E)crenated Answer: c Level: 3 129. Red blood cells (RBCs) have been placed in three different solutions: hypotonic, hypertonic, isotonic. What is solution â€Å"B† relative to the RBC? A)hypotonic solutionB)hypertonic solution C)isotonic solution D)hemolyzed E)crenated Answer: b Level: 3 130. Red blood cells (RBCs) have been placed in three different solutions: hypotonic, hypertonic, isotonic. What is solution â€Å"C† relative to the RBC? A)hypotonic solution B)hypertonic solution C)isotonic solution D)hemolyzed E)crenated Answer: a Level: 3 131. Red blood cells (RBCs) have been placed in three different solutions: hypotonic, hypertonic, isotonic. What is the condition of the RBC in solution â€Å"C†? A)hypotonic solution B)hypertonic solution C)isotonic solution D)hemolyzed E)crenated Answer: d Level: 3 132.Re d blood cells (RBCs) have been placed in three different solutions: hypotonic, hypertonic, isotonic. What is the condition of the RBC in solution â€Å"B†? A)hypotonic solution B)hypertonic solution C)isotonic solution D)hemolyzed E)crenated Answer: e Level: 3 Refer to the following diagram for questions 133-137. [pic] 133. The diagram is an overview of cell metabolism. What does â€Å"A† represent? A)Glucose B)2 lactic acid + 2 ATP C)O2 D)6 CO2 + 6 H2O + 38 ATP E)Pyruvic acid Answer: e Level: 1 134. The diagram is an overview of cell metabolism. What does â€Å"B† represent? A)Glucose B)2 lactic acid + 2 ATP C)O2 D)6 CO2 + 6 H2O + 38 ATP E)Pyruvic acidAnswer: c Level: 1 135. The diagram is an overview of cell metabolism. What does â€Å"C† represent? A)Glucose B)2 lactic acid + 2 ATP C)O2 D)6 CO2 + 6 H2O + 38 ATP E)Pyruvic acid Answer: b Level: 1 136. The diagram is an overview of cell metabolism. What does â€Å"D† represent? A)Glucose B)2 lactic acid + 2 ATP C)O2 D)6 CO2 + 6 H2O + 38 ATP E)Pyruvic acid Answer: a Level: 1 137. The diagram is an overview of cell metabolism. What does â€Å"E† represent? A)Glucose B)2 lactic acid + 2 ATP C)O2 D)6 CO2 + 6 H2O + 38 ATP E)Pyruvic acid Answer: d Level: 1 For questions 138 to 142 match the following processes with the appropriate definition or description.A)requires a carrier molecule but does not use cellular energy B)bulk uptake of material by the formation of a vesicle C)movement of substances from areas of high concentration to areas of less concentration D)movement of water through a selectively permeable membrane E)movement of molecules against their concentration gradient 138. active transport Answer: e Level: 1 139. diffusion Answer: c Level: 1 140. endocytosis Answer: b Level: 1 141. facilitated diffusion Answer: a Level: 1 142. osmosis Answer: d Level: 1 For questions 143 to 147 match the following types of membrane proteins to its function.A)have exposed site on outer cell surface that can attach to ligand B)integral proteins that move ions or molecules across plasma membrane C)form a passageway through the plasma membrane D)allow cells to identify one another E)proteins that can catalyze chemical reactions on inner or outer surface of plasma membrane 143. Marker molecules Answer: d Level: 1 144. Channel protein Answer: c Level: 1 145. Receptor molecules Answer: a Level: 1 146. Enzymes Answer: e Level: 1 147. Carrier proteins Answer: b Level: 1 For questions 148 to 152 match the following cell organelles with the appropriate definition or description.A)source of the spindle fibers B)organelles that produce most of the cell’s energy C)sacs containing hydrolytic enzymes D)sites of protein synthesis E)contains the chromosomes 148. nucleus Answer: e Level: 1 149. ribosomes Answer: d Level: 1 150. lysosomes Answer: c Level: 1 151. mitochondria Answer: b Level: 1 152. centrioles Answer: a Level: 1 For questions 153 to 157 match the followi ng descriptions with the appropriate metabolic pathway. A)aerobic respiration B)anaerobic respiration 153. occurs without oxygen Answer: b Level: 1 154. uses the citric acid cycle and electron transport chain Answer: a Level: 1 155. ccurs in the mitochondria with oxygen Answer: a Level: 1 156. converts pyruvic acid to lactic acid Answer: b Level: 1 157. produces carbon dioxide, water, and ATP Answer: a Level: 1 For questions 158 to 162 match the following cell organelles with the appropriate definition or description. A)organelle where subunits of ribosomes are manufactured B)an organelle of locomotion C)may or may not have ribosomes attached D)small vacuoles containing oxidative enzymes E)package materials for secretion from the cell 158. endoplasmic reticulum Answer: c Level: 1 159. Golgi apparatus Answer: e Level: 1 160. nucleolus Answer: a Level: 1 61. peroxisomes Answer: d Level: 1 162. flagellum Answer: b Level: 1 For questions 163 to 167 match the following stages of the cell cycle with the appropriate description. A)chromosomes align along equator B)cytokinesis is completed at the end of this phase C)time between cell divisions D)chromatin condenses and nucleoli disappear E)chromosomes begin migrating towards poles of the cell 163. interphase Answer: c Level: 1 164. prophase Answer: d Level: 1 165. metaphase Answer: a Level: 1 166. anaphase Answer: e Level: 1 167. telophase Answer: b Level: 1 For questions 168 to 172 match the following molecules with the appropriate escription. A)structural RNA of ribosome B)mRNA containing introns C)protein that is converted to an active enzyme D)all triplets required to code for synthesis of a protein E)three adjacent nucleotides in mRNA 168. pre-mRNA Answer: b Level: 1 169. proenzyme Answer: c Level: 1 170. gene Answer: d Level: 1 171. ribosomal RNA (rRNA) Answer: a Level: 1 172. codon Answer: e Level: 1 For questions 173 to 176 match the cells described with their most abundant organelle. A)mitochondria B)centriol es C)peroxisomes D)lysosomes E) Golgi apparatus 173. white blood cell, a phagocyte Answer: d Level: 2 174. mucus cell (secretes mucus)Answer: e Level: 2 175. liver cells that detoxify hydrogen peroxide Answer: c Level: 2 176. cardiac muscle cells (require large amounts of ATP) Answer: a Level: 2 For questions 177 to 184 match the type of cell division with the appropriate description. A)mitosis B)meiosis C)both mitosis & meiosis 177. Responsible for tissue growth and repair Answer: a Level: 2 178. Resulting cells are haploid Answer: b Level: 2 179. Occurs only in testis and ovary Answer: b Level: 2 180. Daughter cells genetically identical to mother cell Answer: a Level: 2 181. DNA replication occurs only once Answer: c Level: 2 182. Tetrad formation occursAnswer: b Level: 2 183. Cytokinesis occurs only once Answer: a Level: 2 184. Crossing over Answer: b Level: 2 For questions 185 to 189 match the following terms relative to theories about cell death and cell aging to the most appr opriate description. A)portions of DNA are lost over time resulting in cell death B)loss of the energy source in the cell C)genes that turn on late in life that cause cell death D)after a certain amount of time or cell divisions, the cell line dies E)atoms or molecules with unpaired electrons that may damage cells 185. Cellular clock Answer: d Level: 1 186. Mitochondrial damage Answer: bLevel: 1 187. DNA damage Answer: a Level: 1 188. Free radicals Answer: e Level: 1 189. Death gene Answer: c Level: 1 Fill in the Blank 190. The predominant lipid in the cell membrane is a _____________. Answer: phospholipid Level: 1 191. Glycolipids would contain both lipids and _____________. Answer: carbohydrates Level: 1 192. The _____________ contains the genetic information of the cell. Answer: nucleus Level: 1 193. Cytosol is part of _____________. Answer: cytoplasm Level: 1 194. The centrioles are found in a zone of cytoplasm close to the nucleus called the _____________. Answer: centrosome Le vel: 1 195.At the base of each cilium is a structure called the _____________. Answer: basal body Level: 1 196. The shaft of a flagellum contains _____________ microtubule doublets around its periphery. Answer: nine (9) Level: 1 197. _____________ is the force required to prevent the movement of water by osmosis across a semipermeable membrane. Answer: osmotic pressure Level: 1 198. In _____________, ions or molecules move in opposite directions. Answer: counter transport Level: 1 199. _____________ is the sum of catabolism and anabolism. Answer: metabolism Level: 1 200. According to base pair rules, adenine pairs with _____________ in DNA replication.Answer: thymine Level: 1 201. In females, the sex chromosomes look alike and are called _____________. Answer: X chromosomes Level: 1 202. The term for â€Å"programmed cell death† is ______________. Answer: apoptosis Level: 1 Essay Questions 203. Explain what would happen to a cell in each of the following events: a. A cell los t its nucleus b. All the lysosomes ruptured c. The phospholipids in the cell membrane were dissolved d. The cell began losing its mitochondria e. The transfer RNA molecules are selectively destroyed by viruses. Answer: (a) Without a nucleus cells are unable to synthesize mRNA and so cannot complete protein synthesis.Lack of a nucleus also prevents cells from duplicating themselves. A cell without a nucleus will have a short life span and eventually die. (b) Rupture of the lysosomes releases hydrolytic enzymes that begin to digest the cell and kill it. (c) If the phospholipids in the cell membrane are dissolved, the membrane loses its integrity and would no longer function as a selective barrier. (d) Loss of mitochondria reduces the capacity of the cell to generate energy. (e) If transfer RNA molecules are selectively destroyed, protein synthesis would be inhibited as no amino acids would be brought to the ribosomes.Level: 2, 1 204. Adriamycin is a chemotherapeutic drug that binds to DNA and blocks messenger RNA synthesis. Explain why this drug is fatal to a cell. Answer: When adriamycin blocks mRNA synthesis, it also blocks further protein synthesis in those cells. These cells cannot synthesize additional proteins (structural or enzymatic) that they might need. They will soon be unable to function, and they will die. Level: 2 205. Lysosomes remove nonfunctional cell parts. Explain how this function is important to the overall health of the cell. Answer: Nonfunctional cell parts take up valuable space in the cell.They are also composed of molecules that the cell might be able to recycle. It is healthier for the cell to be able to eliminate these nonfunctional parts and possibly reuse some of the molecular components of those parts. Level: 2 206. The cell is compartmentalized by the presence of organelles. What advantage does compartmentalization give to the cell? Answer: Compartmentalization enables cells to specialize internally. By partitioning the interior o f a cell, different functions can be undertaken in different structured compartments within the same cell.This property allows cells to do more than one thing. Level: 2 207. Describe the relationship among ribosomes, ER, the Golgi apparatus, and exocytosis. Answer: Ribosomes are the sites of protein synthesis. Some of the proteins have leader sequences on them, which allow them to be inserted into the cisternae of the endoplasmic reticula to which the ribosomes are attached. The proteins can travel in the endoplasmic reticulum to the Golgi apparatus, where they can be modified and packaged for secretion. Vesicles break off from the flattened membranous sacs of the Golgi apparatus.Some of the vesicles carry proteins to the plasma membrane, where the proteins can be secreted from the cell by exocytosis. Level: 2 208. You work for the I. M. the Best Drug Company. Your latest assignment is to design a drug that interferes with translation in cells. You decide the easiest way to do this is to have your drug target those organelles and molecules involved in translation. List the potential targets of your new drug. Answer: Potential targets include: large and small ribosomal subunits, messenger RNA, transfer RNA, any enzyme needed in translation. Level: 2