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 WohlerB) August KekuléC) Jakob BerzeliusD) Stanley MillerE) Hermann Kolbe

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4) Which pair of molecules shown below are not enantiomers of a single molecule? 4)A)

B)

C)

D)

E)

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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

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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

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13) Research indicates that ibuprofen, a drug used to relieve inflammation and pain, is a mixture oftwo enantiomers; that is, molecules that

13)

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 tetrahedralconfiguration or a planar configuration?

14)

A) the solvent that the organic molecule is dissolved inB) the presence or absence of double bonds between the carbon atom and other atomsC) the polarity of the covalent bonds between carbon and other atomsD) the presence or absence of bonds with nitrogen atomsE) the presence or absence of bonds with oxygen atoms

15) The enzyme amylase can break glycosidic linkages between glucose monomers only if themonomers are the form. Which of the following could amylase break down?

15)

A) chitinB) celluloseC) glycogenD) glycogen, cellulose, and chitinE) glycogen and chitin only

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 chainsB) in the interior of the folded protein, away from waterC) on the exterior surface of the protein, interacting with waterD) in the transmembrane portion interacting with lipid fatty acid chainsE) 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.

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The following questions are based on the 15 molecules illustrated in Figure 5.8. Each molecule may be used once, more thanonce, or not at all.

Figure 5.8

18) Which of the following molecules consists of a hydrophilic "head" region and a hydrophobic "tail"region?

18)

A) 11 B) 2 C) 7 D) 5 E) 9

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Refer to Figure 5.6 to answer the following questions.

Figure 5.6

19) At which bond would water need to be added to achieve hydrolysis of the peptide, back to itscomponent amino acid?

19)

A) A B) B C) C D) D E) E

20) Molecules with which functional groups may form polymers via dehydration reactions? 20)A) either hydroxyl or carboxyl groupsB) either carbonyl or carboxyl groupsC) carbonyl groupsD) carboxyl groupsE) hydroxyl groups

Refer to Figure 5.6 to answer the following questions.

Figure 5.6

21) 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 thesemolecules will be labeled?

22)

A) both phospholipids and nucleic acidsB) nucleic acidsC) phospholipidsD) amyloseE) proteins

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23) If one strand of a DNA molecule has the sequence of bases 5'ATTGCA3', the other complementarystrand would have the sequence

23)

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 helixof DNA?

24)

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.

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 structureB) quaternary structureC) tertiary structureD) primary structureE) secondary, tertiary, and quaternary structures, but not primary structure

28) Which cell would be best for studying lyosomes? 28)A) leaf cell of a plantB) phagocytic white blood cellC) nerve cellD) muscle cellE) bacterial cell

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29) Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cellthrough

29)

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 followingmolecules?

30)

A) celluloseB) glycogenC) nucleic acidsD) lipidsE) proteins

31) Which structure is common to plant and animal cells? 31)A) wall made of celluloseB) centrioleC) central vacuoleD) mitochondrionE) 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) ribosomesB) mitochondriaC) plastidsD) nucleiE) none of these

34) The volume enclosed by the plasma membrane of plant cells is often much larger than thecorresponding volume in animal cells. The most reasonable explanation for this observation is that

34)

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.

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35) Green fluorescent protein (GFP) can be used to fluorescently label a specific protein in cells bygenetically engineering cells to synthesize the target protein fused to GFP. What is the advantage ofusing GFP fusions to visualize specific proteins, instead of staining cells with fluorescently labeledprobes that bind to the target protein?

35)

A) GFP fusions are not subject to artifacts; fluorescent probes may introduce backgroundartifacts.

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.

36) Prokaryotes are classified as belonging to two different domains. What are the domains? 36)A) Archaea and ProtistaB) Bacteria and EukaryaC) Bacteria and FungiD) Bacteria and ArchaeaE) Bacteria and Protista

37) Which structure is the site of the synthesis of proteins that may be exported from the cell? 37)A) lysosomesB) plasmodesmataC) free cytoplasmic ribosomesD) rough ERE) Golgi vesicles

38) Which of the following is present in a prokaryotic cell? 38)A) ribosomeB) nuclear envelopeC) chloroplastD) mitochondrionE) ER

39) Movement of vesicles within the cell depends on what cellular structures? 39)A) actin filaments and microtubulesB) actin filaments and ribosomesC) actin filaments and motor proteinsD) centrioles and motor proteinsE) microtubules and motor proteins

40) Which animal cell organelle contains enzymes that transfer hydrogen from various substrates tooxygen?

40)

A) peroxisomeB) lysosomeC) mitochondrionD) Golgi apparatusE) vacuole

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41) An animal cell lacking oligosaccharides on the external surface of its plasma membrane wouldlikely be impaired in which function?

41)

A) establishing the diffusion barrier to charged moleculesB) maintaining fluidity of the phospholipid bilayerC) attaching to the cytoskeletonD) cell-cell recognitionE) 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 remainfluid when it is extremely cold?

42)

A) by increasing the percentage of unsaturated phospholipids in the membraneB) by cotransport of glucose and hydrogenC) by increasing the percentage of cholesterol molecules in the membraneD) by using active transportE) 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. Similarstalks left in a 0.15 M salt solution become limp and soft. From this we can deduce that the cells ofthe celery stalks are

43)

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.

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.

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47) In receptor-mediated endocytosis, receptor molecules initially project to the outside of the cell.Where do they end up after endocytosis?

47)

A) on the outside of vesiclesB) on the inside surface of the cell membraneC) on the inside surface of the vesicleD) on the ERE) on the outer surface of the nucleus

48) Which of the following processes includes all others? 48)A) diffusion of a solute across a membraneB) facilitated diffusionC) passive transportD) transport of an ion down its electrochemical gradientE) osmosis

49) Some regions of the plasma membrane, called lipid rafts, have a higher concentration of cholesterolmolecules. As a result, these lipid rafts

49)

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 themucus 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 bytransport of sodium and chloride ions across the epithelial cell membrane. How would the lack of afunctional chloride channel in cystic fibrosis patients affect sodium ion transport and the volume ofthe airway surface liquid?

50)

A) Sodium ion transport will be unaffected; lack of chloride transport still reduces osmoticpotential and decreases the airway surface liquid volume.

B) Sodium ion transport will increase; higher osmotic potential will increase airway surfaceliquid volume.

C) Sodium ion transport will increase; higher osmotic potential will decrease airway surfaceliquid volume.

D) Sodium ion transport will decrease; lower osmotic potential will decrease airway surfaceliquid volume.

E) Sodium ion transport will decrease; lower osmotic potential will increase the airway surfaceliquid volume.

51) Which of the following membrane activities require energy from ATP hydrolysis? 51)A) movement of water into a cellB) Na+ ions moving out of a mammalian cell bathed in physiological salineC) facilitated diffusion of chloride ions across the membrane through a chloride channelD) movement of carbon dioxide out of a parameciumE) movement of glucose molecules into a bacterial cell from a medium containing a higher

concentration of glucose than inside the cell

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52) White blood cells engulf bacteria through what process? 52)A) osmosisB) exocytosisC) receptor-mediated exocytosisD) phagocytosisE) 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

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