Chapter 1,2,3

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Chapter 2 1. Which of the following elements have four electrons in their outer shells? A) carbon and silicon B) nitrogen and phosphorus C) flourine and chlorine D) oxygen and sulfur E) boron and aluminum 2. __________ is the smallest chemical unit of a type of pure substance. A) An atom B) A proton C) A molecule D) An amino acid E) A cell 3. The nucleus of an atom is usually made up of: A) protons, neutrons, and proteins that hold them together. B) protons, which have a positive electrical charge, and proteins, which hold them together. C) neutrons, which have no electrical charge. D) neutrinos, which have no electrical charge. E) protons, that which a positive charge, and neutrons, which have no electrical charge. 4. Which five chemical elements make up 93-97% of the biomass in plants, animals, fungi, and bacteria? A) carbon, oxygen, hydrogen, potassium, nitrogen B) carbon, oxygen, hydrogen, sulfur, nitrogen C) carbon, oxygen, hydrogen, nitrogen, phosphorous D) carbon, oxygen, hydrogen, sulfur, phosphorus E) carbon, oxygen, hydrogen, sulfur, potassium 5. Relative to protons: A) electrons have approximately the same mass. B) electrons have a significantly stronger positive charge. C) electrons have significantly greater mass. D) electrons have significantly less mass. E) None of the above; electrons have no mass. 6. Of all the elements that occur on earth, how many are found in your body? A) 90 B) 25 C) 4 D) 10 E) 116 7. An atom of iron has the atomic number 26. This means that: A) it has an atomic mass of 26. B) it has 26 protons. C) it has 13 electrons. D) it has 13 neutrons. E) it has 52 protons. 8. The four most abundant elements in living organisms are: A) sodium, nitrogen, carbon, and silicon. B) carbon, nitrogen, oxygen, and calcium. C) carbon, hydrogen, nitrogen, and phosphorus. D) carbon, nitrogen, potassium, and oxygen. E) hydrogen, nitrogen, oxygen, and carbon. 9. The number of protons in an element, also called its ____________, identifies the element. A) nucleus B) atomic number C) ion D) charge E) atomic weight 10. What is missing from this cell of the periodic table? A) The atomic number for nitrogen, 7 B) The atomic number for nitrogen, 6 C) The atomic number for nitrogen, 8 D) The atomic number for nitrogen, 14 E) The atomic number for nitrogen, 28 11. All matter on earth, both living and non-living, is made up of: A) carbohydrates. B) atoms. C) DNA. D) cells. E) phospholipids. 12. An atom can be changed into an ion by adding or removing: A) a neutron. B) an orbital shell. C) an electron. D) a proton. E) an isotope. 13. Helium is not a reactive molecule because: A) its first-level shell is full with two protons. B) its second-level shell is full with two electrons. C) its first-level shell is full with two neutrons. D) its first-level shell is full with two electrons. E) Helium is a reactive molecule. 14. There are three principal types of bonds that hold multiple atoms together. These are: A) hydrogen bonds, ionic bonds, and glycosidic linkages. B) covalent bonds, ionic bonds, and hydrogen bonds. C) covalent bonds, ionic bonds, and disulfide bonds. D) ionic bonds, hydrogen bonds, and ester bonds. E) phosphate bonds, disulfide bonds, and hydrogen bonds. 15. Multiple atoms linked together are collectively called: A) a molecule. B) an element. C) a reactant. D) a substrate. E) an isotope. 16. Which of the following molecules is NOT formed by covalent bonding? A) NaCl B) H2 C) H2O D) CH4 E) O2 17. One important difference between covalent and ionic bonds is that: A) in covalent bonds two atoms share electrons while in ionic bonds two atoms of opposite charge are attracted to each other. B) ionic bonds only occur among water-soluble elements. C) in ionic bonds two atoms share electrons while in covalent bonds one atom gives one or more electrons to the other atom. D) in ionic bonds both protons and electrons can be shared while in covalent bonds only electrons can be shared. E) ionic bonds are much stronger than covalent bonds. 18. When you put a piece of chocolate on your tongue, your brain registers a sensation of sweetness. What aspect of molecules is responsible for their having a particular taste? A) the ratio of covalent bonds to ionic bonds joining the atoms of the molecule B) the shape of the molecule C) the total number of protons in the molecule D) the total number of electron shells in the atoms of the molecule E) the amount of hydrogen bonds in the molecule (more hydrogen bonds = sweeter taste) 19. Water molecules form which type of bond with other water molecules? A) disulfide bridges B) ionic bonds C) hydrogen bonds D) covalent bonds E) Van der waals bonds 20. How many hydrogen bonds are explicitly represented in this figure? A) 8 B) 4 C) 0 D) 1 E) 10 21. The tendency of molecules to stick together, called cohesion, is stronger in water than in other liquids because: A) the polarity of water allows an oxygen atom from one water molecule to form a hydrogen bond with the oxygen atom of another water molecule. B) the polarity of water allows a hydrogen atom from one water molecule to form a hydrogen bond with the oxygen atom of another water molecule. C) the polarity of water allows a hydrogen atom from one water molecule to form an ionic bond with the oxygen atom of another water molecule. D) the polarity of water allows a hydrogen atom from one water molecule to form a hydrogen bond with the hydrogen atom of another water molecule. E) the polarity of water allows a hydrogen atom from one water molecule to form a covalent bond with the oxygen atom of another water molecule. 22. The most abundant molecule in the cell is: A) cellulose. B) oxygen. C) water. D) carbohydrate. E) carbon dioxide. 23. Why do coastal areas have milder, less variable climates than inland areas? A) Because water is a good solvent, it is able to dissolve the photons in light, reducing their ability to heat or cool the land. B) Large bodies of water have high salt concentrations and salt absorbs a large proportion of the light energy that would have warmed the land. C) Coastal areas are concentrated near the equator, which varies less than other parts of the globe in the angle at which the sun's light hits it. D) Large bodies of water, especially oceans, can absorb huge amounts of heat from the sun during warm times of the year, reducing temperature increases on the land. Similarly, during cold times of year the ocean slowly cools, giving off heat that reduces the temperature drop on shore. E) None of the above. No one knows why coastal areas have milder, less variable climates than inland areas. 24. A chemical compound that releases OH- into a solution is called: A) a base. B) a salt. C) a solvent. D) a hydroxide ion. E) an acid. 25. The pH of a fluid is a measure of: A) its capacity to function as a soap. B) how acidic or basic it is. C) the amount of adenosine triphosphate (ATP) in it. D) its enzymatic stability. E) the concentration of phosphate groups. 26. A buffer is a chemical that: A) can quickly absorb excess H+ ions to keep a solution from becoming too acidic. B) can quickly release H+ ions to counteract any increases in the OH- concentration in a solution. C) is identical to baking soda. D) restores the pH of a solution to 7.0. E) a) and b) are both true. 27. Certain molecules act like bank accounts for H+ ions because they can absorb excess H+ ions to keep a solution from becoming too acidic and release H+ ions to keep the solution from becoming too basic. Such molecules are called: A) catalysts. B) buffers. C) reducing agents. D) oxidating agents. E) enzymes. 28. A solution's acidity is: A) a measure of its negative charge (the stronger the negative charge, the more acidic the substance). B) a measure of the number of nucleotide bases in the solution. C) a measure of the amount of buffer molecules in the solution. D) a measure of the number of all dissolved molecules in a solution. E) a measure of the H+ (free-floating protons) in it. 29. Pure water and aqueous solutions that are neither acidic nor basic are said to be: A) buffers. B) neutral. C) translucent. D) transparent. E) alkaline. 30. Urine, with a pH of 6, is _________ times more acidic than seawater, with a pH of 8. A) 10 B) 8 C) 6 D) 1,000 E) 100 31. Which of the following statements is true about acids and bases? A) Acids and bases do not react with each other. B) Acids mixed with bases neutralize each other. C) Acids mixed with bases make stronger acids. D) Acids will neutralize bases, but bases will not neutralize acids. E) Bases will neutralize acids, but acids will not neutralize bases. 32. Carbohydrates: A) act as a relatively quickly available source of fuel. B) serve as carbon skeletons that can be rearranged to form other molecules that are essential for biological structures and functions like nucleic acids. C) in the form of oligosaccharides are often covalently bonded to proteins and lipids on the outer cell surface, where they serve as cell recognition signals. D) are a good source of sustained energy when they come in the form of polysaccharides. E) All of the above. 33. Energy used in cellular respiration can originate from: A) carbohydrates and proteins only. B) carbohydrates, proteins, and fats. C) fats only. D) carbohydrates only. E) proteins only. 34. Which of the following are all monosaccharides? A) glucose, fructose, and galactose B) starch, cellulose, and glycogen C) fructuse and cellulose D) glucose and maltose E) glycogen and glucose 35. Lactose is a combination of: A) glucose and ribose. B) sucrose and fructose. C) glucose and galactose. D) glucose and maltose. E) glucose and fructose. 36. A complex polymer built of monosaccharides is called a(n): A) polypeptide. B) polysaccharide. C) protein. D) ketone. E) aldehyde. 37. Glycogen belongs in the class of molecules known as: A) amino acids. B) monosaccharides. C) proteins. D) polysaccharides. E) nucleic acids. 38. Sucrose (table sugar) and lactose (the sugar found in milk) are examples of: A) simple sugars. B) polyunsaccharide sugars. C) disaccharides. D) monosaccharides. E) naturally occurring enzymes. 39. Which of the following is a polysaccharide? A) glucose, the chief cellular energy source B) cellulose, the primary component of plant cell walls C) fructose, one of the most important blood sugars D) insulin, the chief blood sugar regulator E) All of the above are polysaccharides. 40. On food packages, "insoluble fiber" refers to plant material that we can't fully digest but is important for maintaining a healthy digestive tract. This substance refers to a(n): A) amino acid. B) carbohydrate. C) protein. D) lipid. E) nucleic acid. 41. Which of the following statements about cellulose is FALSE? A) The cellulose we eat passes right through our digestive system unused. B) Cellulose has a slightly different three-dimensional structure from starch. C) Although it is not digestible, cellulose is still important to humans' diets. D) Cellulose and starch are made from similar molecules. E) All of the above statements about cellulose are TRUE. 42. Which of the following is not an important biological function of lipids? A) insulation B) regulation of growth and development C) energy storage D) protection of internal organs and tissues E) All of the above are true. 43. The figure represents which class of chemical compounds? A) fats B) acids C) sterols D) carbohydrates E) proteins 44. All lipids are: A) polymers of fatty acids. B) not soluble in water. C) triglycerides. D) polar. E) hydrophilic. 45. An unsaturated fatty acid is one in which: A) carbon-carbon double bonds are present in the hydrocarbon chain. B) not all of the carbons in the hydrocarbon chain are bonded to hydrogen atoms. C) there is an odd number of subunits in the hydrocarbon chain. D) there is an even number of subunits in the hydrocarbon chain. E) carbon-carbon double bonds are not present in the hydrocarbon chain. 46. Organic molecules consisting of only hydrogen and carbon are called: A) carbohydrates. B) enantiomers. C) hydrocarbons. D) fats. E) hydroxyls. 47. Saturated fatty acids have _________________ than unsaturated fatty acids, which is why they exist as a ____________ at room temperature. A) more carbon atoms; solid B) fewer double bonds; solid C) more double bonds; liquid D) fewer hydrogen atoms; solid E) more glycerol molecules; liquid 48. Which statement about phospholipids is FALSE? A) They are hydrophilic at one end. B) They contain glycerol linked to fatty acids. C) They are a major constituent of cell membranes. D) They are hydrophobic on one end. E) Because their phosphate groups repel each other, they are used as organisms' chief form of short-term energy. 49. The principal components of cell membranes are: A) carbohydrates. B) nucleic acids. C) lipids. D) glycoproteins. E) proteins. 50. Phospholipids assemble spontaneously into bilayers driven by the attraction of their "tail" portions to each other and of their "head" portions to each other. The tail regions are: A) hydrophilic. B) cohesive. C) hydrophobic. D) molecularly charged. E) adhesive.

Answer Key 1. A 2. A 3. E 4. C 5. D 6. B 7. B 8. E 9. B 10. A 11. B 12. C 13. D 14. B 15. A 16. A 17. A 18. B 19. C 20. B 21. B 22. C 23. D 24. A 25. B 26. E 27. B 28. E 29. B 30. E 31. B 32. E 33. B 34. A 35. C 36. B 37. D 38. C 39. B 40. B 41. E 42. E 43. C 44. B 45. A 46. C 47. B 48. E 49. C 50. C 51. A 52. D 53. E 54. C 55. E 56. C 57. E 58. E 59. E 60. B 61. E 62. E 63. A 64. B 65. A 66. E 67. A 68. D 69. B 70. C 71. C 72. E 73. D 74. D

Ch. 3 1. Which of the following is NOT true of ALL cells? A) They eliminate wastes. B) They assimilate nutrients. C) They move by means of flagella or cilia. D) They have DNA as their genetic material. E) They synthesize new cellular material. 2. Which statement is NOT part of the modern cell theory? A) All living organisms consist of one or more cells. B) The first cell arrived on earth from outer space. C) Cellular reactions include both energy-releasing and biosynthetic types. D) Cells contain hereditary information that passes from one generation of cells to the next. E) Cells arise from other cells. 3. Interacting systems of molecules enclosed in compartments called __________ evolved 3.8 billion years ago in living organisms. A) brains B) organs C) circulatory systems D) mitochondria E) cells 4. Which of the following is found in both prokaryotic and eukaryotic cells? A) Golgi apparatus B) ribosome C) centriole D) lysosome E) peroxisome 5. Prokaryotic organisms lack: A) replicator molecules (DNA or RNA). B) cell membranes. C) metabolism. D) organelles. E) All of the above. 6. Which of the following is a cellular characteristic of ALL eukaryotes? A) a nuclear membrane B) few to no organelles in the cytoplasm C) a cell wall D) a nucleoid E) few to no proteins associated with the DNA 7. Eukaryotic cells may contain all of the following EXCEPT: A) a membrane-bound nucleus. B) a peptidoglycan cell wall. C) flagella. D) photosynthetic pigments. E) ribosomes. 8. According to the theory of endosymbiosis, the origin of chloroplasts probably involved: A) the formation of cell walls around the photosynthetic pigments. B) the formation of colonies of cyanobacteria. C) engulfing of small photosynthetic prokaryotes by larger cells. D) the accumulation of free oxygen in ocean waters. E) All of the above are correct. 9. The malarial Plasmodium and its relatives, the apicomplexans, are not capable of photosynthesis, yet they have a distinctive organelle—the apicoplast—that has four membranes and contains DNA closely related to the DNA found in chloroplasts. The presence of the apicoplast in the apicomplexans supports which of the following hypotheses? A) The apicomplexans are closely related to cyanobacteria. B) The apicomplexans are closely related to land plants. C) The apicomplexans were once capable of photosynthesis. D) The apicoplast arose via endosymbiosis. E) The apicoplast has no function. 10. The object depicted in the figure: A) is a bacterial cell. B) could be either a plant or an animal cell. C) is a plant cell. D) is an animal cell. E) is a ribosome. 11. Which of the following facts supports the claim that mitochondria developed from bacteria that were long ago phagocytosed into eukaryotic cells? A) Mitochondria have proteins for the synthesis of ATP. B) Mitochondria have their own DNA. C) Mitochondria are the "powerhouses" of the cell. D) Mitochondria have flagella for motion. E) Mitochondria are small and easily transported across the membrane. 12. Mitochondria are thought to have evolved from free-living bacteria that were incorporated into eukaryotic cells by endosymbiosis. Which of the following pieces of evidence for this hypothesis is INCORRECT? A) Mitochondria are enclosed by two membranes rather than a single membrane. B) Mitochondrial DNA is packaged as a single circular chromosome, like that of a bacterium. C) The phospholipid composition of the inner mitochondrial membrane is similar to that of the bacterial cell membrane. D) Mitochondria can survive and reproduce independently when removed from the host cell. E) New mitochondria are formed by binary fission rather than being replicated during the cell cycle. 13. The lipids within the fluid mosaic of the plasma membranes are held in place by: A) covalent bonds. B) hydrophobic interactions. C) hydrogen bonds. D) disulfide bridges. E) ionic bonds. 14. What are the two distinct "faces" of the phospholipids that make up the surface membrane of a cell? A) a hydrophilic head and a hydrophobic tail B) a hydrophobic head and a hydrophilic tail C) a phosphate group head and two fatty acid tails D) Both a) and c) are correct. E) Both b) and c) are correct. 15. Which cellular structure makes it possible for a cell to differ structurally and biochemically from its surroundings? A) nucleolus B) nucleus C) plasma membrane D) cell wall E) endoplasmic reticulum 16. How are phospholipid molecules that make up the surface membrane of a cell organized? A) A single-layered structure is formed, with the hydrophobic heads facing in to the interior of the cell and the hydrophobic tails on the outside, facing the exterior environment. B) A single-layered structure is formed, with the hydrophobic tails facing in to the interior of the cell and the hydrophobic head on the outside, facing the exterior environment. C) A two-layered structure is formed, with the hydrophobic tails facing in to each other, sandwiched between the hydrophilic heads that face the interior of the cell and the exterior environment. D) A two-layered structure is formed, with the hydrophobic heads facing in to each other, sandwiched between the hydrophilic tails on the outside that face interior of the cell and the exterior environment. E) Both b) and d) are possible. 17. What is the most important barrier protecting the inner contents of an animal cell from its exterior environment? A) the cellular membrane B) the cell wall C) the nucleus D) the cytoskeleton E) Both a) and b) are correct. 18. Phospholipids assemble spontaneously into bilayers driven by the attraction of their "tail" portions to each other and of their "head" portions to each other. The tail regions are: A) cohesive. B) adhesive. C) hydrophilic. D) hydrophobic. E) molecularly charged. 19. Which of the following is NOT an important structural feature on the surface membrane of an animal cell? A) lipid bilayer B) cholesterol C) cell wall D) glycoproteins E) sugar molecules 20. Which of the following is the outermost feature on the surface of a plant cell? A) lipid bilayer B) cholesterol C) cell wall D) glycoproteins E) sugar molecules 21. "Beta-blockers" do all of the following EXCEPT: A) block signaling through adrenaline receptors. B) reduce outward symptoms of anxiety. C) bind to the cytoplasmic side of a receptor protein. D) reduce high blood pressure. E) reduce the effects of adrenaline on the heart. 22. The figure shows the action of beta-blockers in reducing anxiety. In this diagram, the triangular wedges represent ________________, the figures with rectangular tops and triangular bottoms represent ______________, and the ovals represent ______________. A) beta-blocker chemicals; adrenaline; beta-receptors B) adrenaline; beta-blocker chemicals; beta-receptors C) adrenaline; beta-receptors; beta-blocker chemicals D) beta-blocker chemicals; mucus; beta-receptors E) mucus; beta-blocker chemicals; beta-receptors 23. Which of the following is the most important factor governing a cell's particular type of interaction with other cells? A) The type of animal the cell came from B) The location of the cell within an organism C) Whether or not the cell is an animal cell or a plant cell D) The pattern of proteins on the cell's surface E) Whether or not the cell is eukaryotic or prokaryotic 24. In the figure, the round, knobby structures are _______________ and the Y-shaped post-like structures with semi-circular receptors are ________________. A) beta-blocker chemicals; beta receptors B) adrenaline molecules; beta receptors C) HIV particles; liver cell molecular fingerprints D) HIV particles; CD4 markers E) beta-blocker chemicals; adrenaline molecules 25. The net movement of molecules from locally concentrated regions to uniform distributions is best described as: A) active transport. B) passive transport. C) diffusion. D) enthalpy. E) concentration gradient. 26. The primary function of molecular membranes is the transport of ions and molecules in and out of cells—transport is directional and selective. The moving of molecules from areas of high concentration to that of low concentration to gain energy is best described as: A) channel mediated diffusion. B) electron transport. C) active transport. D) inactivated transport. E) passive transport. 27. Which of the following BEST defines diffusion? A) net movement of particles between cells B) net movement of fluids from the environment into and out of an organism C) net movement of particles from a cell into the extracellular matrix D) net movement of particles from areas of low concentration to areas of high concentration E) net movement of particles from areas of high concentration to areas of low concentration 28. Sugar and CO2 are dissolved in water to make carbonated soft drinks. Which of the following is the solute? A) the water and the sugar B) the water and the CO2 C) the CO2 only D) the sugar and the CO2 E) the sugar only 29. If the concentrations of a particular molecule are equal on both sides of the membrane, facilitated diffusion will: A) insure that the molecule becomes concentrated outside the cell. B) insure that the molecule stays impermeable to the membrane. C) insure that the molecule becomes concentrated inside the cell. D) insure that the concentrations inside and outside the cell are both increased. E) be ineffective. 30. In aquatic environments, water moves _____________. A) down the water concentration scale B) against the water concentration gradient C) up the water concentration scale D) down the water concentration gradient E) up the water concentration gradient 31. A cell's interior is considered isotonic to the surrounding fluid when: A) the solute concentration is lower within the cell than outside the cell. B) the cell's lipid bilayer does not allow any molecules to pass into or out of the cell. C) the solute concentration is higher within the cell than outside the cell. D) there is an equal number of water molecules immediately outside the cell as inside the cell. E) the solute concentrations are the same within and outside the cell. 32. The passive transport of water across a membrane from a solution of lower solute concentration to a solution of higher solute concentration is best described as: A) active transport. B) general diffusion. C) osmosis. D) passive transport. E) facilitated diffusion. 33. If the solution surrounding a cell contains less solute than the cytoplasm, the osmotic condition is said to be: A) hypotonic. B) adiabatic. C) isobaric. D) hypertonic. E) isotonic. 34. Osmosis is _________ specialized than diffusion because it involves _________. A) more; water B) more; acids C) less; acids D) less; all liquids E) more; bases 35. You are bored at a lunch meeting and surreptitiously place a raisin in your glass of water. The raisin swells to twice its original size. Relative to the water, the raisin must have been: A) hypertonic. B) isotonic. C) hypotonic. D) mesotonic. E) osmotic. 36. Which of the following BEST summarizes the differences between osmosis and diffusion? A) Diffusion deals only with water. B) Osmosis deals only with water. C) Diffusion deals only with alkaline liquids. D) Osmosis deals only with alkaline liquids. E) Osmosis deals only with acidic liquids. 37. Active transport, the moving of molecules from areas of low concentration to that of high concentration across the membrane, is usually coupled to processes that: A) counteract osmotic stress. B) establish a dynamic equilibrium with no net gain or loss in energy for the cell. C) gain energy for the cell. D) amplify cellular response to signal molecules. E) cost energy. 38. The movement of H+ into the stomach represented in this figure is accomplished through: A) osmosis. B) simple diffusion. C) endocytosis. D) active transport. E) facilitated diffusion. 39. The primary function of molecular membranes is the transport of ions and molecules in and out of cells. The movement of molecules from areas of low concentration to those of high concentration against chemical gradients is best described as: A) channel mediated diffusion. B) passive transport. C) active transport. D) electron transport. E) inactivated transport. 40. You measure the concentration of a polar molecule inside and outside of a cell. You find that the concentration is high and gradually increasing inside the cell. You also measure the ATP concentration inside the cell and find that it is dropping. What would be your best hypothesis for the process that is occurring? A) facilitated diffusion B) active transport C) endocytosis D) passive transport E) simple diffusion 41. To absorb large particles, cells engulf them within their plasma membrane in a process called: A) replication. B) exocytosis. C) endocytosis. D) transcription. E) translation. 42. ______________ are found in all metabolically active cells and are involved primarily in transporting materials within, into, and out of cells. A) Vesicles B) Ribosomes C) Peroxisomes D) Vacuoles E) Lysosomes 43. Membrane-bound vesicles containing a substance synthesized by a cell fuse to the outer cell membrane and release their contents to the outside world. What is this process called? A) exocytosis B) pinocytosis C) endocytosis D) excretocytosis E) phagocytosis 44. Which of the following is a correct description of how exocytosis functions in transporting molecules across the cellular membrane? A) Vesicles are filled with molecules in the interior of the cell and then fuse with the membrane to deposit the molecules outside of the cell. B) A receptor protein on the outside of the cell binds a particular biochemical, causing the membrane to form an indetation and bring the biochemical into the cell. C) Protein molecules on the interior of the cellular membrane trap molecules attached on the exterior side and bring them into the cell. D) Nutrients are moved within the cell from one tightly woven network to another. E) None of the above is correct. 45. Mammalian cells take in many molecules including hormones, antibodies, and blood proteins. This process is coordinated by proteins that recognize their specific target molecule. This process is best described as: A) phagocytosis. B) active transport. C) exocytosis. D) receptor-mediated endocytosis. E) pinocytosis. 46. Secretion of cell products like milk proteins and mucus from glandular cells is accomplished via: A) exocytosis. B) facilitated diffusion. C) active transport. D) passive transport. E) endocytosis. 47. Which of the following cell membrane components are present in plant cells but absent in animal cells? A) phospholipids B) gap junctions C) plasmodesmata D) proteins E) carbohydrates 48. Which of the following is NOT a way in which the cell's surface membrane interacts with the exterior environment? A) The cellular surface mediates attachments to other cells. B) The cellular surface receives and transmits incoming messages. C) The cellular surface mediates interactions with extracellular material. D) The cellular surface controls which substances enter and leave the cell. E) The cellular surface organizes the interior organelle organization of the cell. 49. The cell connections represented in the figure are: A) lysosomes. B) tight junctions. C) plasmodesmata. D) gap junctions. E) desmosomes. 50. Nuclear ______ are specialized holes in the ________- layered nuclear envelope that separates the nucleus from the ___________. A) pores; one; endoplasmic reticulum B) passageways; one; cytoplasm C) pores; two; cytoplasm D) vesicles; three; endoplasmic reticulum E) vesicles; two; cytoplasm

Answer Key 1. C 2. B 3. E 4. B 5. D 6. A 7. B 8. C 9. D 10. D 11. B 12. D 13. B 14. D 15. C 16. C 17. A 18. D 19. C 20. C 21. C 22. B 23. D 24. D 25. C 26. E 27. E 28. D 29. E 30. D 31. E 32. C 33. A 34. A 35. A 36. B 37. E 38. D 39. C 40. B 41. C 42. A 43. A 44. A 45. D 46. A 47. C 48. E 49. E 50. C 51. A 52. E 53. B 54. D 55. C 56. D 57. E 58. A 59. B 60. A 61. E 62. C 63. A 64. B 65. B 66. E 67. B 68. D 69. A 70. A 71. D 72. D 73. D 74. A 75. C

Chap 1 1. The proposed explanation for a phenomenon is BEST described as: A) a testable prediction. B) an observation. C) a hypothesis. D) a theory. E) an experiment. 2. Which of the following is MOST correct? A) Accepting or rejecting a hypothesis is the same as proving whether or not the hypothesis is true. B) By rejecting a hypothesis, you also reject any theory that was correlated with that hypothesis. C) You can prove a hypothesis to be true. D) You can accept or reject a hypothesis, but never prove it to be true. E) You can prove a hypothesis to be false. 3. If your hypothesis is "Estrogens in sewage runoff turn fish into hermaphrodites," what is your null hypothesis? A) Estrogens in sewage runoff turn turtles into hermaphrodites. B) Estrogens in sewage runoff have no effect in turning fish into hermaphrodites. C) Testosterones in sewage runoff have no effect in turning fish into hermaphrodites. D) Testosterones in sewage runoff turn fish into hermaphrodites. E) Estrogens in sewage runoff turn hermaphroditic fish into unisexual fish. 4. When conducting a scientific experiment, which of the following is tested? A) a prediction B) a result C) a theory D) a question E) an observation 5. After generating a hypothesis, a scientist next: A) does an experiment. B) formulates a theory. C) writes a grant proposal. D) makes a prediction. E) designs a series of tests. 6. If your hypothesis is "Echinacea reduces the duration and severity of the common cold," which of the following is the BEST testable prediction for this hypothesis? A) If echinacea reduces the duration and severity of the symptoms of the common cold, then individuals taking echinacea should get sick less frequently than those not taking it. B) If echinacea reduces the duration and severity of the symptoms of the common cold, then individuals taking echinacea should get sick less frequently than those not taking it, and when they do get sick, their illness should not last as long. C) If echinacea reduces the duration and severity of the symptoms of the common cold, then individuals taking echinacea should get sick more frequently than those not taking it, and when they do get sick, their illness should last longer. D) If echinacea reduces the duration and severity of the symptoms of the common cold, then individuals taking echinacea who get sick should have illness that do not last as long. E) None of the above is a reasonable testable prediction for this hypothesis. 7. Kyle Lohse is currently a starting pitcher for the St. Louis Cardinals. Interestingly, there have been only nine players in major league history who have had the first name "Kyle," and ALL NINE HAVE BEEN PITCHERS. You hypothesize that there is a causal connection between having the name Kyle and becoming a pitcher. Which of the following is a reasonable testable prediction for your hypothesis? A) Examination of the list of all minor league players named Kyle will reveal that they are all pitchers as well. B) A random, double-blind survey of little league coaches will reveal that when they have a player named Kyle they make that player into a pitcher. C) A random, double-blind survey of American parents who have named their child Kyle will reveal that they wanted their child to be a pitcher. D) All of the above are reasonable testable predictions for the hypothesis. E) Only b) and c) are reasonable testable predictions for the hypothesis. 8. A _____________ is a pill that looks identical to a pill that contains the active ingredient in a scientific trial, but contains no active ingredient itself. A) tablet B) barbiturate C) placebo D) capsule E) treatment 9. Once a scientist has formulated a hypothesis that generates a testable prediction, she will: A) draw conclusions. B) make revisions. C) conduct a critical experiment. D) formulate a second hypothesis. E) make observations. 10. When conducting a critical experiment to test whether taking echinacea reduces the duration or severity of a cold, which of the following is NOT an important step? A) providing some groups with echinacea and others with a placebo B) providing some groups with treatments of longer duration than others C) randomly dividing volunteers into treatment groups D) exposing some groups, but not others, to the cold virus E) All of the above are important steps. 11. Some have claimed that the herb echinacea reduces the likelihood of catching the common cold. In many hundreds of studies, this claim has been refuted. Assuming these studies were properly conducted, which of the following is a scientifically responsible claim that an echinacea advocate could make in support of further research on this subject. A) The effective dosage of echinacea was outside the range of the dosages given in the scientific studies. B) The investigators were paid off by the drug companies. C) The effective length of time needed for taking echinacea is longer than that provided in any of the scientific studies. D) All of the above are scientifically responsible claims that an echinacea advocate could make in support of further research on this subject. E) Only a) and c) scientifically responsible claims that an echinacea advocate could make in support of further research on this subject. 12. Which of the following is the BEST way to state the relationship between "data" and "results"? A) "Data" are the facts you collect from your experiment, while "results" are your interpretation of what the data mean. B) Any two scientists reporting the same "results" must have been using the same "data." C) "Data" and "results" are two names for the same thing. D) The "data" section should always come before the "results" section in a scientific paper. E) Any two scientists examining the same "data" would draw the same "results." 13. If your hypothesis is rejected, then: A) you may still have learned something important about the system you were testing. B) you should change the level of statistical significance until your hypothesis is accepted. C) your experiment was poorly designed. D) your experiment was a success. E) your experiment was a failure. 14. If the results of an experiment turn out differently from what you expected, then: A) you didn't follow the scientific method. B) your instruments were probably at fault. C) you need to redo your experiment until you get the expected result. D) you should explore the reasons for this in the "conclusions" section of your experimental write-up. E) your experiment was a failure. 15. If you conduct an experiment that rejects your hypothesis, then: A) your experiment was poorly designed. B) you should change your major. C) you should publish your results anyway. D) your experiment was a failure. E) the null hypothesis was a better fit to your data. 16. Which of the following is NOT an example of a theory? A) Diseases are caused by germs. B) Molecules are composed of atoms. C) Organisms are composed of cells. D) Species evolve through natural selection. E) All of the above are considered to be theories. 17. A scientific theory is one that: A) is supported by many years of experimentation all supporting the hypothesis. B) is based on hunches with no actual supporting evidence. C) sounds the most plausible. D) is the result of all scientific experiments. E) changes each time a different observation is made. 18. In science, theories tend to be ______________________ than hypotheses. A) more experimental B) more empirical C) less scientific D) more speculative E) broader in scope 19. Scientific theories do not represent speculations or guesses about the natural world. Rather they are hypotheses—proposed explanations for natural phenomena—that have been: A) found to be statistically significant. B) used to support the political stances of the scientists that have developed them. C) validated by the International Board of Scientific Theories. D) verified by at least one critical experiment. E) so strongly and persuasively supported by empirical observation that the scientific community views them as unlikely to be altered by new evidence. 20. In controlled experiments: A) one variable is manipulated while others are held constant. B) all variables are held constant. C) all critical variables are manipulated. D) all variables are dependent on each other. E) all variables are independent of each other. 21. In a randomized, controlled, double-blind study: A) experimental subjects are blind-folded when given the experimental treatment. B) individuals will be assigned to an experimental or control group depending on whether or not they took part in a pilot study. C) all experimental variables are held constant. D) neither the experimenter nor the subject know whether the subject is in a control group or an experimental group. E) All of the above. 22. An experimental condition applied to research subjects is called a: A) control. B) treatment. C) variable. D) randomization. E) placebo. 23. The placebo effect: A) demonstrates that most scientific studies cannot be replicated. B) reveals that experimental treatments cannot be proven as effective. C) reveals that sugar pills are generally as effective as actual medications in fighting illness. D) is an urban legend. E) is the frequently observed, poorly understood, phenomenon that people tend to respond favorably to any treatment. 24. Which of the following is the BEST description of a control group in an experiment? A) The control group is identical to each test group except for one variable. B) The control group is a test group which is chosen at random. C) There should be more than one control group in any experiment. D) The control group and the test groups may have several differences between them. E) There can be more than one difference between the control group and test groups, but not several differences or else the experiment is invalid. 25. If a researcher uses the same experimental setup as another study to collect data, but uses different research subjects, it is considered: A) extrapolation. B) exploration. C) replication. D) a two-tailed test of the hypothesis. E) inductive reasoning. 26. Which of the following is an important feature of the scientific method? A) Anyone should be able to repeat an experiment. B) Once demonstrated, conclusions cannot be changed. C) If research results are not conclusive, the opinion of experts should be relied upon. D) A researcher's methods should not be described once desired results have been obtained. E) A good hypothesis does not necessarily need to be tested. 27. In a scientific experiment, a control group: A) is less important than an experimental group. B) can be compared with an experimental group to assess whether one particular variable is causing a change in the experimental group. C) must be kept in a laboratory. D) makes the experiment better, but is not essential. E) All of the above are correct. 28. Alon claimed that a tincture of a local herb was effective in lowering anxiety and was planning to invest in the product. As evidence of his claim, Alon, who had anxiety over his financial situation, said that he felt much better after the treatment, was much more relaxed, and no longer worried about his finances. Which of the following combinations of methodological flaws BEST characterizes Alon's investigation? A) lack of appropriate controls and lack of an appropriate outcome measure B) lack of appropriate outcome measure, replication, randomization, and controls C) lack of replication and lack of appropriate controls D) lack of an appropriate outcome measure E) lack of randomization, lack of replication, and lack of an appropriate outcome measure 29. A powerful way to demonstrate that observed differences between a treatment group and a control group truly reflect the effect of the treatment is for researchers: A) to get their study published in a scientific journal. B) make more observations. C) to conduct the experiment over and over again. D) formulate as many hypotheses as they can. E) to use a variety of statistical tests until they find one that shows statistical significance. 30. What is the best way for a scientist to address his/her own biases? A) There is no way a scientist can deal with biases. B) use careful controls to minimize them C) understand his/her biases and interpret the data differently as a result D) make sure that no biases influence his/her work E) never be involved any kind of scientific study where his/her possible biases might impact the study 31. _________________ may have biases that affect their abilities to perform in an objective fashion. A) Research assistants B) Scientists C) Authors of Prep-U questions D) Politicians E) All of the above are correct. 32. Statistical methods make it possible to: A) unambiguously learn the truth. B) choose the best answer to value-based questions. C) test non-falsifiable hypotheses. D) determine how likely it is that certain results may have occurred by chance. E) reject any hypothesis. 33. If a report states, "the female subjects in the study are 5 feet 6 inches ± 3 inches," this indicates that: A) 90% of the women are between 5 feet 3 inches and 5 feet 9 inches. B) the variation among all women is 3 inches in height. C) all of the women are between 5 feet 3 inches and 5 feet 9 inches. D) two thirds of the women are between 5 feet 3 inches and 5 feet 9 inches. E) the investigator is unsure of her data. 34. The set of analytical and mathematical tools designed to help researchers gain understanding from the data they gather is called: A) experimentation. B) statistics. C) geometry. D) genetics. E) biology. 35. Suppose you measure the height of two people. One is a woman who is 5 feet 10 inches tall. The other is a man who is 5 feet 6 inches tall. Which of the following is an appropriate conclusion to draw from these measurements? A) Some men are taller than some women. B) Men are taller than women. C) Some women are taller than some men. D) The tallest woman is 5 feet 10 inches tall. E) Women are taller than men. 36. If you toss a coin and it comes up tails on eight consecutive tosses, what is the likelihood it will come up heads on the ninth toss? A) 1 B) 1/2 C) 0 D) 5/9 E) 4/9 37. When comparing two groups, _________________________ the more confident we are of the conclusion that there is a significant difference in the groups. A) the larger the variation in each group B) the fewer the number of individuals in each group C) the more variables we measure D) the smaller the difference between the two groups E) the smaller the variation in each group 38. In a series of studies, researchers found a statistically significant positive correlation between the number of fire-fighters present at a fire and the amount of damage that the fire does. Which of the following is the BEST conclusion to be drawn from these studies? A) Statistical data must be put in its proper context to be understood. B) To more accurately estimate the effect of the number of fire-fighters on the amount of damage, we would need to compare the amount of damage from fires of different sizes that are fought by similar numbers of fire-fighters. C) Fire-fighters make fires worse. D) Causation is not correlation. E) Fire-fighters are effective in fighting fires. 39. Which of the following statements BEST explains the observation that there are more autism cases now than in the past? A) There are more parents who neglect their children, which is a cause of autism, now than in the past. B) Autism has been selected for in recent generations by natural selection. C) The vaccine for measles, mumps, and rubella has been established as a significant cause of autism. D) Doctors are more aware of the condition and have better techniques for diagnosing and reporting it. E) All of the above are equally good explanations for the observation that there are more autism cases now than in the past. 40. When a chewing gum manufacturer makes the claim, "Four out of five dentists surveyed recommend sugarless gum for their patients that chew gum," how many dentists need have been surveyed for the statement to be factually accurate? A) five B) at least one hundred C) at least five hundred D) ten E) four 41. Anecdotal evidence: A) is a more efficient method for understanding the world than the scientific method. B) is often the only way to prove important causal links between two phenomena. C) can appear to reveal links between two phenomena that do not actually exist. D) tends to be more reliable than data based on observations of large numbers of diverse individuals. E) is a necessary part of the scientific method. 42. Pseudoscience capitalizes on the belief shared by most people that: A) the scientific bases for scientific-sounding claims are often not clear. B) scientific claims can be evaluated through the political process. C) scientific thinking is a powerful method for learning about the world. D) scientific thinking is beyond the reach of the average person. E) science is intimidating. 43. Science as a way of seeking principles of order differs from art, religion, and philosophy in that: A) science limits its search to the natural world of the physical universe. B) science deals exclusively with known facts. C) science denies the existence of the supernatural. D) there is no room for intuition or guessing. E) all scientific knowledge is gained by experimentation. 44. All of the following are branches of science EXCEPT: A) zoology. B) physics. C) geology. D) astronomy. E) logic. 45. How can science best help each of us understand the role of humans in nature? A) Science can provide us with a set of moral precepts. B) Science can provide understanding of how the systems of nature work. C) Science can provide us with a specific political agenda. D) Science can teach us to love nature. E) None of the above is correct. 46. Which of the following terms and phrases best describes the application of scientific knowledge to specific purposes? A) deduction B) technology C) junk science D) statistics E) pseudoscience 47. Which of the following questions would be LEAST helped by application of the scientific method? A) evaluating the relationship between violence in videogames and criminal behavior in teens B) comparing the effectiveness of two potential antibiotics C) formulating public policy on euthanasia D) determining the most effective safety products for automobiles E) developing more effective high school curricula 48. Why is it that creationism can never be accepted as a scientific explanation of the origin of life? A) Because the age of the earth, as given in Genesis, can never be determined. B) Because the ideas of creationism cannot be tested through experiment and observation. C) Because creationism, like evolution, is a theory and therefore cannot be proved. D) Because most scientists are not deeply religious people. E) None of the above; creationism can be accepted as a scientific explanation of the origin of life. 49. Which of the following questions CANNOT be answered by the scientific method? A) Is eyewitness testimony is criminal proceedings reliable? B) Does chemical runoff give rise to hermaphrodite fish? C) Does hair that is shaved grow back coarser? D) Does taking echinacea reduce the intensity or duration of the common cold? E) Did the United States act appropriately when it invaded Iraq? 50. The scientific method will never prove or disprove: A) the existence of God. B) the beauty of Shakespeare's sonnets. C) the ability of echinacea to prevent the common cold. D) All of the above are examples of statements that the scientific method will never prove or disprove. E) Only a) and b) are examples of statements that the scientific method will never prove or disprove.

Answer Key 1. C 2. D 3. B 4. A 5. D 6. B 7. A 8. C 9. C 10. D 11. E 12. A 13. A 14. D 15. E 16. E 17. D 18. E 19. E 20. A 21. D 22. B 23. E 24. A 25. C 26. A 27. B 28. B 29. C 30. B 31. E 32. D 33. D 34. B 35. C 36. B 37. E 38. A 39. D 40. A 41. C 42. C 43. A 44. E 45. B 46. B 47. C 48. B 49. E 50. E 51. E 52. C 53. E 54. D 55. B 56. B 57. E 58. D 59. C 60. A 61. A 62. B 63. E 64. D 65. D 66. E 67. C 68. B 69. E 70. E 71. C 72. E 73. B 74. A 75. A


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