MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Transcription

1 STUDY GUIDE Chapters 4-7_ MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The complexity and variety of organic molecules is due to 1) A) their interaction with water. B) the variety of rare elements in organic molecules. C) their tremendously large sizes. D) the chemical versatility of carbon atoms. E) the fact that they can be synthesized only in living organisms. 2) Which functional group(s) shown above is (are) present in all amino acids? 2) A) A and B B) B and D C) C only D) D only E) C and D 3) Which of the following people used this apparatus to study the formation of organic compounds? 3) A) Friedrich Wohler B) August Kekulé C) Jakob Berzelius D) Stanley Miller E) Hermann Kolbe 1

2 4) Which pair of molecules shown below are not enantiomers of a single molecule? 4) A) B) C) D) E) 2

3 5) Which of the structures illustrated above contain(s) a carbonyl functional group? 5) A) A B) C and D C) C D) D E) C and E 6) Which molecule shown above is a thiol? 6) A) A B) B C) C D) D E) E 7) Which molecule shown above has a carbonyl functional group in the form of an aldehyde? 7) A) A B) B C) C D) D E) E 3

4 8) The two molecules shown in the figure above are best described as 8) A) structural isomers. B) chain length isomers. C) enantiomers. D) cis-trans isomers. E) optical isomers. 9) Which functional group is not present in this molecule? 9) A) sulfhydryl B) carboxyl C) amino D) hydroxyl 10) Which of the following statements best describes the carbon atoms present in a seed-eating bird? 10) A) They were incorporated into organic molecules by plants, they were processed into sugars through photosynthesis, and they are ultimately derived from carbon dioxide. B) They are ultimately derived from carbon dioxide. C) They were incorporated into organic molecules by plants. D) They were processed into sugars through photosynthesis. E) They were incorporated into organic molecules by plants, and they are ultimately derived from carbon dioxide. 11) Which molecule shown above has a carbonyl functional group in the form of a ketone? 11) A) A B) B C) C D) D E) E 12) Which of the following hydrocarbons has a double bond in its carbon skeleton? 12) A) CH4 B) C2H4 C) C2H2 D) C3H8 E) C2H6 4

5 13) Research indicates that ibuprofen, a drug used to relieve inflammation and pain, is a mixture of two enantiomers; that is, molecules that A) differ in the arrangement of atoms around their double bonds. B) have identical chemical formulas but differ in the branching of their carbon skeletons. C) exist in either linear chain or ring forms. D) differ in the location of their double bonds. E) are mirror images of one another. 14) What determines whether a carbon atom's covalent bonds to other atoms are in a tetrahedral configuration or a planar configuration? A) the solvent that the organic molecule is dissolved in B) the presence or absence of double bonds between the carbon atom and other atoms C) the polarity of the covalent bonds between carbon and other atoms D) the presence or absence of bonds with nitrogen atoms E) the presence or absence of bonds with oxygen atoms 15) The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are the form. Which of the following could amylase break down? A) chitin B) cellulose C) glycogen D) glycogen, cellulose, and chitin E) glycogen and chitin only 13) 14) 15) 16) In a normal cellular protein, where would you expect to find a hydrophobic amino acid like valine? 16) A) in the interior of the folded protein, away from water, or in a transmembrane portion interacting with lipid fatty acid chains B) in the interior of the folded protein, away from water C) on the exterior surface of the protein, interacting with water D) in the transmembrane portion interacting with lipid fatty acid chains E) anywhere in the protein, with equal probability 17) Which of the following statements about the 5' end of a polynucleotide strand of DNA is correct? 17) A) The 5' end is the fifth position on one of the nitrogenous bases. B) The 5' end has a hydroxyl group attached to the number 5 carbon of ribose. C) The 5' end has a carboxyl group attached to the number 5 carbon of ribose. D) The 5' end has a phosphate group attached to the number 5 carbon of ribose. E) The 5' end has phosphate attached to the number 5 carbon of the nitrogenous base. 5

6 The following questions are based on the 15 molecules illustrated in Figure 5.8. Each molecule may be used once, more than once, or not at all. Figure ) Which of the following molecules consists of a hydrophilic "head" region and a hydrophobic "tail" region? A) 11 B) 2 C) 7 D) 5 E) 9 18) 6

7 Refer to Figure 5.6 to answer the following questions. Figure ) At which bond would water need to be added to achieve hydrolysis of the peptide, back to its component amino acid? A) A B) B C) C D) D E) E 19) 20) Molecules with which functional groups may form polymers via dehydration reactions? 20) A) either hydroxyl or carboxyl groups B) either carbonyl or carboxyl groups C) carbonyl groups D) carboxyl groups E) hydroxyl groups Refer to Figure 5.6 to answer the following questions. Figure ) Which bond is closest to the amino terminus of the molecule? 21) A) A B) B C) C D) D E) E 22) If cells are grown in a medium containing radioactive 32P-labeled phosphate, which of these molecules will be labeled? A) both phospholipids and nucleic acids B) nucleic acids C) phospholipids D) amylose E) proteins 22) 7

8 23) If one strand of a DNA molecule has the sequence of bases 5'ATTGCA3', the other complementary strand would have the sequence A) 5'TGCAAT3'. B) 5'UGCAAU3'. C) 5'UAACGU3'. D) 3'UAACGU5'. E) 5'TAACGT3'. 24) Which of the following pairs of base sequences could form a short stretch of a normal double helix of DNA? A) 5'-GCGC-3' with 5'-TATA-3' B) 5'-purine-pyrimidine-purine-pyrimidine-3' with 3'-purine-pyrimidine-purine-pyrimidine-5' C) 5'-ATGC-3' with 5'-GCAT-3' D) 5'-AGCT-3' with 5'-TCGA-3' E) All of these pairs are correct. 23) 24) 25) A molecule with the formula C18H36O2 is probably a 25) A) carbohydrate. B) hydrocarbon. C) protein. D) nucleic acid. E) fatty acid. 26) Which of the following statements concerning unsaturated fats is true? 26) A) They are more common in animals than in plants. B) They have fewer fatty acid molecules per fat molecule. C) They have double bonds in the carbon chains of their fatty acids. D) They generally solidify at room temperature. E) They contain more hydrogen than do saturated fats having the same number of carbon atoms. 27) What aspects of protein structure are stabilized or assisted by hydrogen bonds? 27) A) secondary structure B) quaternary structure C) tertiary structure D) primary structure E) secondary, tertiary, and quaternary structures, but not primary structure 28) Which cell would be best for studying lyosomes? 28) A) leaf cell of a plant B) phagocytic white blood cell C) nerve cell D) muscle cell E) bacterial cell 8

9 29) Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through A) intermediate filaments. B) gap junctions. C) desmosomes. D) plasmodesmata. E) tight junctions. 30) Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules? A) cellulose B) glycogen C) nucleic acids D) lipids E) proteins 29) 30) 31) Which structure is common to plant and animal cells? 31) A) wall made of cellulose B) centriole C) central vacuole D) mitochondrion E) chloroplast 32) Why isn't the mitochondrion classified as part of the endomembrane system? 32) A) Its structure is not derived from the ER or Golgi. B) It is not attached to the outer nuclear envelope. C) It has too many vesicles. D) It is a static structure. E) It is not involved in protein synthesis. 33) Which type of organelle is found in plant cells but not in animal cells? 33) A) ribosomes B) mitochondria C) plastids D) nuclei E) none of these 34) The volume enclosed by the plasma membrane of plant cells is often much larger than the corresponding volume in animal cells. The most reasonable explanation for this observation is that A) plant cells contain a large vacuole that reduces the volume of the cytoplasm. B) animal cells are more spherical, whereas plant cells are elongated. C) plant cells have a much more highly convoluted (folded) plasma membrane than animal cells. D) plant cells can have lower surface-to-volume ratios than animal cells because plant cells synthesize their own nutrients. E) plant cells are capable of having a much higher surface-to-volume ratio than animal cells. 34) 9

10 35) Green fluorescent protein (GFP) can be used to fluorescently label a specific protein in cells by genetically engineering cells to synthesize the target protein fused to GFP. What is the advantage of using GFP fusions to visualize specific proteins, instead of staining cells with fluorescently labeled probes that bind to the target protein? A) GFP fusions are not subject to artifacts; fluorescent probes may introduce background artifacts. B) GFP fusions enable higher resolution than staining with fluorescent probes. C) GFP fusions enable one to track changes in the location of the protein in living cells; staining usually requires preserved cells. D) GFP permits the position of the protein in the cell more precisely than fluorescent probes. E) GFP permits visualization of protein-protein interactions; fluorescent probes do not. 35) 36) Prokaryotes are classified as belonging to two different domains. What are the domains? 36) A) Archaea and Protista B) Bacteria and Eukarya C) Bacteria and Fungi D) Bacteria and Archaea E) Bacteria and Protista 37) Which structure is the site of the synthesis of proteins that may be exported from the cell? 37) A) lysosomes B) plasmodesmata C) free cytoplasmic ribosomes D) rough ER E) Golgi vesicles 38) Which of the following is present in a prokaryotic cell? 38) A) ribosome B) nuclear envelope C) chloroplast D) mitochondrion E) ER 39) Movement of vesicles within the cell depends on what cellular structures? 39) A) actin filaments and microtubules B) actin filaments and ribosomes C) actin filaments and motor proteins D) centrioles and motor proteins E) microtubules and motor proteins 40) Which animal cell organelle contains enzymes that transfer hydrogen from various substrates to oxygen? A) peroxisome B) lysosome C) mitochondrion D) Golgi apparatus E) vacuole 40) 10

11 41) An animal cell lacking oligosaccharides on the external surface of its plasma membrane would likely be impaired in which function? A) establishing the diffusion barrier to charged molecules B) maintaining fluidity of the phospholipid bilayer C) attaching to the cytoskeleton D) cell-cell recognition E) transporting ions against an electrochemical gradient 42) Which of the following is one of the ways that the membranes of winter wheat are able to remain fluid when it is extremely cold? A) by increasing the percentage of unsaturated phospholipids in the membrane B) by cotransport of glucose and hydrogen C) by increasing the percentage of cholesterol molecules in the membrane D) by using active transport E) by decreasing the number of hydrophobic proteins in the membrane 43) Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a 0.15 M salt solution become limp and soft. From this we can deduce that the cells of the celery stalks are A) hypertonic to fresh water but hypotonic to the salt solution. B) hypertonic to both fresh water and the salt solution. C) isotonic with fresh water but hypotonic to the salt solution. D) hypotonic to fresh water but hypertonic to the salt solution. E) hypotonic to both fresh water and the salt solution. 41) 42) 43) 44) Water passes quickly through cell membranes because 44) A) it moves through hydrophobic channels. B) water movement is tied to ATP hydrolysis. C) it is a small, polar, charged molecule. D) the bilayer is hydrophilic. E) it moves through aquaporins in the membrane. 45) In a paramecium, cell surface integral membrane proteins are synthesized 45) A) in the cytoplasm by free ribosomes. B) by ribosomes bound to the rough endoplasmic reticulum. C) by ribosomes in the nucleus. D) by ribosomes bound to the inner surface of the plasma membrane. E) by ribosomes in the Golgi vesicles. 46) In order for a protein to be an integral membrane protein it would have to be 46) A) exposed on only one surface of the membrane. B) hydrophilic. C) amphipathic, with at least one hydrophobic region. D) completely covered with phospholipids. E) hydrophobic. 11

12 47) In receptor-mediated endocytosis, receptor molecules initially project to the outside of the cell. Where do they end up after endocytosis? A) on the outside of vesicles B) on the inside surface of the cell membrane C) on the inside surface of the vesicle D) on the ER E) on the outer surface of the nucleus 47) 48) Which of the following processes includes all others? 48) A) diffusion of a solute across a membrane B) facilitated diffusion C) passive transport D) transport of an ion down its electrochemical gradient E) osmosis 49) Some regions of the plasma membrane, called lipid rafts, have a higher concentration of cholesterol molecules. As a result, these lipid rafts A) have higher rates of lateral diffusion of lipids and proteins into and out of the lipid rafts. B) are more rigid than the surrounding membrane. C) detach from the plasma membrane and clog arteries. D) are able to flip from inside to outside. E) are more fluid than the surrounding membrane. 50) In the small airways of the lung, a thin layer of liquid is needed between the epithelial cells and the mucus layer in order for cilia to beat and move the mucus and trapped particles out of the lung. One hypothesis is that the volume of this airway surface liquid is regulated osmotically by transport of sodium and chloride ions across the epithelial cell membrane. How would the lack of a functional chloride channel in cystic fibrosis patients affect sodium ion transport and the volume of the airway surface liquid? A) Sodium ion transport will be unaffected; lack of chloride transport still reduces osmotic potential and decreases the airway surface liquid volume. B) Sodium ion transport will increase; higher osmotic potential will increase airway surface liquid volume. C) Sodium ion transport will increase; higher osmotic potential will decrease airway surface liquid volume. D) Sodium ion transport will decrease; lower osmotic potential will decrease airway surface liquid volume. E) Sodium ion transport will decrease; lower osmotic potential will increase the airway surface liquid volume. 49) 50) 51) Which of the following membrane activities require energy from ATP hydrolysis? 51) A) movement of water into a cell B) Na+ ions moving out of a mammalian cell bathed in physiological saline C) facilitated diffusion of chloride ions across the membrane through a chloride channel D) movement of carbon dioxide out of a paramecium E) movement of glucose molecules into a bacterial cell from a medium containing a higher concentration of glucose than inside the cell 12

13 52) White blood cells engulf bacteria through what process? 52) A) osmosis B) exocytosis C) receptor-mediated exocytosis D) phagocytosis E) pinocytosis For the following questions, match the labeled component of the cell membrane in the figure with its description. 53) Which component is a glycolipid? 53) A) A B) B C) C D) D E) E 13