Biology 110 Multiple Choice Questions

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178. Which of the following is a statement of the first law of thermodynamics? A) Energy cannot be created or destroyed. B) The entropy of the universe is decreasing. C) The entropy of the universe is constant. D) Kinetic energy is stored energy that results from the specific arrangement of matter. E) Energy cannot be transferred or transformed.

A

181. A chemical reaction that has a positive ΔG is correctly described as A) endergonic. B) endothermic. C) enthalpic. D) spontaneous. E) exothermic.

A

69.Which of the following happens at the conclusion of meiosis I? A) Homologous chromosomes are separated. B) The chromosome number per cell is conserved. C) Sister chromatids are separated. D) Four daughter cells are formed. E) The sperm cells elongate to form a head and a tail end

A

74.Meiosis II is similar to mitosis in that A) sister chromatids separate during anaphase. B) DNA replicates before the division. C) the daughter cells are diploid. D) homologous chromosomes synapse. E) the chromosome number is reduced.

A

83. What was the most significant conclusion that Gregor Mendel drew from his experiments with pea plants? A) There is considerable genetic variation in garden peas. B) Traits are inherited in discrete units, and are not the results of "blending." C) Recessive genes occur more frequently in the F1 generation than do dominant ones. D) Genes are composed of DNA. E) An organism that is homozygous for many recessive traits is at a disadvantage.

B

85. Why did Mendel continue some of his experiments to the F2 or F3 generation? A) to obtain a larger number of offspring on which to base statistics B) to observe whether or not a recessive trait would reappear C) to observe whether or not the dominant trait would reappear D) to distinguish which alleles were segregating E) to be able to describe the frequency of recombination

B

92) Labrador retrievers are black, brown, or yellow. In a cross of a black female with a brown male, results can be either all black puppies, 1/2 black to 1/2 brown puppies, or 3/4 black to 1/4 yellow puppies. How many genes must be responsible for these coat colors in Labrador retrievers? A) 1 B) 2 C) 3 D) 4 E) 5

B

108. What is the difference between covalent bonds and ionic bonds? A) Covalent bonds are formed between atoms to form molecules; ionic bonds are formed between atoms to form compounds B) Covalent bonds involve the sharing of pairs of electrons between atoms; ionic bonds involve the sharing of single electrons between atoms. C) Covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the electrical attraction between atoms. D) Covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the sharing of protons between atoms. E) Covalent bonds involve the transfer of electrons between atoms; ionic bonds involve the sharing of electrons between atoms.

C

112. A covalent chemical bond is one in which A) electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged. B) protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms. C) outer-shell electrons of two atoms are shared so as to satisfactorily fill the outer electron shells of both atoms. D) outer-shell electrons of one atom are transferred to fill the inner electron shell of another atom. E) an electron occupies a hybrid orbital located between the nuclei of two atoms.

C

189. Which of the following is (are) true for anabolic pathways? A) They do not depend on enzymes. B) They are usually highly spontaneous chemical reactions. C) They consume energy to build up polymers from monomers. D) They release energy as they degrade polymers to monomers. E) They consume energy to decrease the entropy of the organism and its environment.

C

192. Which of the following shows the correct changes in thermodynamic properties for a chemical reaction in which amino acids are linked to form a protein? A) +ΔH, +ΔS, +ΔG B) +ΔH, -ΔS, -ΔG C) +ΔH, -ΔS, +ΔG D) -ΔH, -ΔS, +ΔG E) -ΔH, +ΔS, +ΔG

C

198. When a glucose molecule loses a hydrogen atom as the result of an oxidation-reduction reaction, the molecule becomes A) hydrolyzed. B) hydrogenated. C) oxidized. D) reduced.

C

2.A localized group of organisms that belong to the same species is called a A) biosystem B) community C) population D) ecosystem E) family

C

200. In addition to ATP, what are the end products of glycolysis? A) CO2 and H2O B) CO2 and pyruvate C) NADH and pyruvate D) CO2 and NADH E) H2O, FADH2, and citrate

C

205. During aerobic respiration, H2O is formed. Where does the oxygen atom for the formation of the water come from? A) carbon dioxide (CO2) B) pyruvate (C3H3O3-) C) molecular oxygen (O2)

C

206. Where is ATP synthase located in the mitochondrion? A) cytosol B) outer membrane C) inner membrane

C

208. Which of the following normally occurs regardless of whether or not oxygen (O2) is present? A) fermentation B) citric acid cycle C) glycolysis

C

21.When biologists wish to study the internal ultrastructure of cells, they can achieve the finest resolution by using A) a phase-contrast light microscope B) a scanning electron microscope C) a transmission electric microscope D) a confocal fluorescence microscope E) a super-resolution fluorescence microscope

C

210. Why is glycolysis considered to be one of the first metabolic pathways to have evolved? A) It relies on chemiosmosis, which is a metabolic mechanism present only in the first cells' prokaryotic cells. B) It is found in prokaryotic cells but not in eukaryotic cells. C) It does not involve organelles or specialized structures, does not require oxygen, and is present in most organisms.

C

220. The alternative pathways of photosynthesis using the C4 or CAM systems are said to be compromises. Why? A) Each one minimizes both water loss and rate of photosynthesis. B) C4 compromises on water loss and CAM compromises on photorespiration. C) Both minimize photorespiration but expend more ATP during carbon fixation. D) CAM plants allow more water loss, while C4 plants allow less CO2 into the plant. E) C4 plants allow less water loss but CAM plants allow more water loss.

C

223. How is photosynthesis similar in C4 plants and CAM plants? A) In both cases, only photosystem I is used. B) Both types of plants make sugar without the Calvin cycle. C) In both cases, rubisco is not used to fix carbon initially. D) Both types of plants make most of their sugar in the dark. E) In both cases, thylakoids are not involved in photosynthesis.

C

227. In autotrophic bacteria, where are the enzymes located that can carry on carbon fixation (reduction of carbon dioxide to carbohydrate)? A) in chloroplast membranes B) in chloroplast stroma C) in the cytosol D) in the nucleoid E) in the infolded plasma membrane

C

228. In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from A) the stroma to the photosystem II. B) the matrix to the stroma. C) the stroma to the thylakoid space. D) the intermembrane space to the matrix. E) the thylakoid space to the stroma.

C

229. In photosynthetic cells, synthesis of ATP by the chemiosmotic mechanism occurs during A) photosynthesis only. B) respiration only. C) both photosynthesis and respiration. D) neither photosynthesis nor respiration. E) photorespiration only.

C

232. The nitrogenous base adenine is found in all members of which group? A) proteins, triglycerides, and testosterone B) proteins, ATP, and DNA C) ATP, RNA, and DNA D) α glucose, ATP, and DNA E) proteins, carbohydrates, and ATP

C

102. The nucleus of a nitrogen atom contains 7 neutrons and 7 protons. Which of the following is a correct statement concerning nitrogen? A) The nitrogen atom has a mass number of approximately 7 daltons and an atomic mass of 14. B) The nitrogen atom has a mass number of approximately 14 daltons and an atomic mass of 7. C) The nitrogen atom has a mass number of 14 and an atomic mass of 7 grams. D) The nitrogen atom has a mass number of 7 and an atomic number of 14. E) The nitrogen atom has a mass number of 14 and an atomic mass of approximately 14 daltons.

E

107. What bonding or interaction is most likely to occur among a broad array of molecules of various types (polar, nonpolar, hydrophilic, hydrophobic)? A) covalent bonding B) polar covalent bonding C) ionic bonding D) hydrogen bonding E) van der Waals interactions

E

117. Molecules with which functional groups may form polymers via dehydration reactions? A) hydroxyl groups B) carbonyl groups C) carboxyl groups D) either carbonyl or carboxyl groups E) either hydroxyl or carboxyl groups

E

123. A molecule with the chemical formula C6H12O6 is probably a A) carbohydrate. B) lipid. C) monosaccharide D) carbohydrate and lipid only. E) carbohydrate and monosaccharide only.

E

132. What aspects of protein structure are stabilized or assisted by hydrogen bonds? A) primary structure B) secondary structure C) tertiary structure D) quaternary structure E) secondary, tertiary, and quaternary structures, but not primary structure

E

136. How do we describe transformation in bacteria? A) the creation of a strand of DNA from an RNA molecule B) the creation of a strand of RNA from a DNA molecule C) the infection of cells by a phage DNA molecule D) the type of semiconservative replication shown by DNA E) assimilation of external DNA into a cell

E

156. Who was/were the first to propose that cell membranes are phospholipid bilayers? A) H. Davson and J. Danielli B) I. Langmuir C) C. Overton D) S. Singer and G. Nicolson E) E. Gorter and F. Grendel

E

166. Water passes quickly through cell membranes because A) the bilayer is hydrophilic. B) it moves through hydrophobic channels. C) water movement is tied to ATP hydrolysis. D) it is a small, polar, charged molecule. E) it moves through aquaporins in the membrane.

E

236. Which of the following does not occur in prokaryotic eukaryotic gene expression, but does in eukaryotic gene expression? A) mRNA, tRNA, and rRNA are transcribed. B) RNA polymerase binds to the promoter. C) A poly-A tail is added to the 3' end of an mRNA and a cap is added to the 5' end. D) Transcription can begin as soon as translation has begun even a little. E)RNA polymerase requires a primer to elongate the molecule.

C

239. In the structural organization of many eukaryotic genes, individual exons may be related to which of the following? A) the sequence of the intron that immediately precedes each exon B) the number of polypeptides making up the functional protein C) the various domains of the polypeptide product D) the number of restriction enzyme cutting sites E) the number of start sites for transcription

C

247. Which of the following is true of transcription in domain Archaea? A) It is regulated in the same way as in domain Bacteria. B) There is only one kind of RNA polymerase. C) It is roughly simultaneous with translation. D) Promoters are identical to those in domain Eukarya. E) It terminates in a manner similar to bacteria.

C

25.Large numbers of ribsoomes are present in cells that specialize in producing which of the following molecules? A) lipids B) glycogen C) proteins D) cellulose E) nucleic acids

C

27.Which type of organelle or structure is primarily involved in the synthesis of oils,phospholipids, and steroids? A) ribosomes B) lysosome C) smooth endoplasmic reticulum D) mitochondrion E) contractile vacuole

C

29.Which organelle is the primary site of ATP synthesis in eukaryotic cells? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

C

100. Knowing just the atomic mass of an element allows inferences about which of the following? A) the chemical properties of the element B) the number of protons in the element C) the number of neutrons in the element D) the number of protons plus neutrons in the element E) both the number of protons and the chemical properties of the element

D

101. In what way are elements in the same column of the periodic table the same? A) They have the same number of protons. B) They have the same number of neutrons. C) They have the same number of electrons. D) They have the same number of electrons in their valence shell. E) They have the same number of electron shells.

D

105. What is the maximum number of hydrogen atoms that can be covalently bonded in a molecule containing two carbon atoms? A) 2 B) 3 C) 4 D) 6 E) 8

D

109. Which of the following molecules contains the most polar covalent bond? A) H2 B) O2 C) CO2 D) H2O E) CH4

D

11.What is the major distinguishing characteristic of fungi? A) gaining nutrition through ingestion B) being sedentary C) being prokaryotic D) absorbing dissolved nutrients E) being decomposer of dead organisms

D

111. When two atoms are equally electronegative, they will interact to form A) hydrogen bonds. B) van der Waals interactions. C) polar covalent bonds. D) nonpolar covalent bonds. E) ionic bonds.

D

114. Two atoms appear to have the same mass number. These atoms A) must have the same atomic number. B) must have the same number of electrons. C) must have the same chemical properties. D) must have the same number of protons + neutrons. E) must have the same atomic number, the same number of protons + neutrons, the same number of electrons, and the same chemical properties.

D

116. Humans and mice differ because A) their cells have different small organic molecules. B) their cells make different types of large biological molecules. C) their cells make different types of lipids. D) their cells have some differences in the sequence of nucleotides in their nucleic acids. E) their cells make different types of proteins.

D

13.Which of the following is a correct sequence of levels in life's hierarchy, proceeding downward from an individual animal? A) brain, organ system, nerve cell, nervous tissue B) organ system, nervous tissue, brain C) organism, organ system, tissue, cell, organ D) nervous system, brain, nervous tissue, nerve cell E) organ system, tissue, molecule, cell

D

147.Which of the following statements describes the eukaryotic chromosome? A) It is composed of DNA alone. B) The nucleosome is its most basic functional subunit. C) The number of genes on each chromosome is different in different cell types of an organism. D) It consists of a single linear molecule of double-stranded DNA plus proteins. E) Active transcription occurs on heterochromatin but not euchromatin.

D

152. The elongation of the leading strand during DNA synthesis A) progresses away from the replication fork. B) occurs in the 3' → 5' direction. C) produces Okazaki fragments. D) depends on the action of DNA polymerase. E) does not require a template strand.

D

157. Singer and Nicolson's fluid mosaic model of the membrane proposed that A) membranes are a phospholipid bilayer. B) membranes are a phospholipid bilayer between two layers of hydrophilic proteins. C) membranes are a single layer of phospholipids and proteins. D) membranes consist of protein molecules embedded in a fluid bilayer of phospholipids. E) membranes consist of a mosaic of polysaccharides and proteins

D

162. Which of the following is true of the evolution of cell membranes? A) Cell membranes have stopped evolving now that they are fluid mosaics. B) Cell membranes cannot evolve if the membrane proteins do not. C) The evolution of cell membranes is driven by the evolution of glycoproteins and glycolipids. D) All components of membranes evolve in response to natural selection. E) An individual organism selects its preferred type of cell membrane for particular functions.

D

171. Ions diffuse across membranes through specific ion channels A) down their chemical gradients. B) down their concentration gradients. C) down the electrical gradients. D) down their electrochemical gradients. E) down the osmotic potential gradients.

D

172. An organism with a cell wall would most likely be unable to take in materials through A) diffusion. B) osmosis. C) active transport. D) phagocytosis. E) facilitated diffusion.

D

177. Which of the following is an example of potential rather than kinetic energy? A) the muscle contractions of a person mowing grass B) water rushing over Niagara Falls C) light flashes emitted by a firefly D) a molecule of glucose E) the flight of an insect foraging for food

D

180. Chemical equilibrium is relatively rare in living cells. Which of the following could be an example of a reaction at chemical equilibrium in a cell? A) a reaction in which the free energy at equilibrium is higher than the energy content at any point away from equilibrium B) a chemical reaction in which the entropy change in the reaction is just balanced by an opposite entropy change in the cell's surroundings C) an endergonic reaction in an active metabolic pathway where the energy for that reaction is supplied only by heat from the environment D) a chemical reaction in which both the reactants and products are not being produced or used in any active metabolic pathway E) no possibility of having chemical equilibrium in any living cell

D

20.When applying the process of science, which of these is tested? A) a question B) a result C) an observation D) a prediction E) a hypothesis

D

211. Most CO2 from catabolism is released during A) oxidative phosphorylation. B) electron transport. C) lactate fermentation. D) the citric acid cycle

D

214. In a plant cell, where are the ATP synthase complexes located? A) thylakoid membrane only B) plasma membrane only C) inner mitochondrial membrane only D) thylakoid membrane and inner mitochondrial membrane E) thylakoid membrane and plasma membrane

D

222. Which of the following statements is a correct distinction between autotrophs and heterotrophs? A) Only heterotrophs require chemical compounds from the environment. B) Cellular respiration is unique to heterotrophs. C) Only heterotrophs have mitochondria. D) Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic. E) Only heterotrophs require oxygen.

D

224. Which process is most directly driven by light energy? A) creation of a pH gradient by pumping protons across the thylakoid membrane B) carbon fixation in the stroma C) reduction of NADP+ molecules D) removal of electrons from chlorophyll molecules E) ATP synthesis

D

230. The splitting of carbon dioxide to form oxygen gas and carbon compounds occurs during A) photosynthesis. B) respiration. C) both photosynthesis and respiration. D) neither photosynthesis nor respiration. E) photorespiration.

D

233. Which of the following nucleotide triplets best represents a codon? A) a triplet separated spatially from other triplets B) a triplet that has no corresponding amino acid C) a triplet at the opposite end of tRNA from the attachment site of the amino acid D) a triplet in the same reading frame as an upstream AUG E) a sequence in tRNA at the 3' end

D

234. Which of the following provides some evidence that RNA probably evolved before DNA? A) RNA polymerase uses DNA as a template. B) RNA polymerase makes a single-stranded molecule. C) RNA polymerase does not require localized unwinding of the DNA. D) DNA polymerase uses primer, usually made of RNA. E) DNA polymerase has proofreading function.

D

237. Transcription in eukaryotes requires which of the following in addition to RNA polymerase? A) the protein product of the promoter B) start and stop codons C) ribosomes and tRNA D) several transcription factors (TFs) E) aminoacyl synthetase

D

24.Which organelle or structure is absent in plant cells? A) mitochondria B) Golgi vesicles C) microtubules D) centrosomes E) peroxisomes

D

241. Which of the following is a function of a signal peptide? A) to direct an mRNA molecule into the cisternal space of the ER B) to bind RNA polymerase to DNA and initiate transcription C) to terminate translation of the messenger RNA D) to translocate polypeptides across the ER membrane E) to signal the initiation of transcription

D

243. Why might a point mutation in DNA make a difference in the level of protein's activity? A) It might result in a chromosomal translocation. B) It might exchange one stop codon for another stop codon. C) It might exchange one serine codon for a different serine codon. D) It might substitute an amino acid in the active site. E) It might substitute the N-terminus of the polypeptide for the C-terminus.

D

244. Which of the following mutations is most likely to cause a phenotypic change? A) a duplication of all or most introns B) a large inversion whose ends are each in intergenic regions C) a nucleotide substitution in an exon coding for a transmembrane domain D) a single nucleotide deletion in an exon coding for an active site E) a frameshift mutation one codon away from the 3' end of the nontemplate strand

D

33.In a plant cell, DNA may be found A) only in the nucleus B) only in the nucleus and mitochondria C) only in the nucleus and chloroplasts D) in the nucleus, mitochondria, and chloroplasts E) in the nucleus, mitochondria, chloroplasts, and peroxisomes

D

35.What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell? A) ER → Golgi → nucleus B) Golgi →ER →lysosome C) nucleus →ER →Golgi D) ER →Golgi →vesicles that fuse with plasma membrane E) ER →lysosomes →vesicles that fuse with plasma membrane

D

45.Movement of the chromosomes during anaphase would be most affected by a drug that A) reduces cyclin concentrations. B) increases cyclin concentrations. C) prevents elongation of microtubules. D) prevents shortening of microtubules. E) prevents attachment of the microtubules to the kinetochore.

D

56.Which of the following most accurately describes a cyclin? A) It is present in similar concentrations throughout the cell cycle. B) It is activated to phosphorylate by complexing with a Cdk. C) It decreases in concentration when MPF activity increases. D) It activates a Cdk molecule when it is in sufficient concentration. E) It activates a Cdk when its concentration is decreased.

D

72.Which life cycle stage is found in plants but not animals? A) gamete B) zygote C) multicellular diploid D) multicellular haploid E) unicellular diploid

D

168. The phosphate transport system in bacteria imports phosphate into the cell even when the concentration of phosphate outside the cell is much lower than the cytoplasmic phosphate concentration. Phosphate import depends on a pH gradient across the membrane-more acidic outside the cell than inside the cell. Phosphate transport is an example of A) passive diffusion. B) acilitated diffusion. C) active transport. D) osmosis. E) cotransport.

E

175. Which term most precisely describes the cellular process of breaking down large molecules into smaller ones? A) catalysis B) metabolism C) anabolism D) dehydration E) catabolism

E

179. A system at chemical equilibrium A) consumes energy at a steady rate. B) releases energy at a steady rate. C) consumes or releases energy, depending on whether it is exergonic or endergonic. D) has zero kinetic energy. E) can do no work.

E

19.A filamentous organisms has been isolated from decomposing organic matter. This organisms has a cell wall but no chloroplasts. how would you classify this organism? A) domain Bacteria, kingdom Prokaryota B) domain Archaea, kingdom Bacteria C) domain Eukarya, kingdom Plantae D) domain Eukarya, kingdom Protista E) domain Eurkarya, kingdom Fungi

E

191. Which of the following is the smallest closed system? A) a cell B) an organism C) an ecosystem D) Earth E) the universe

E

203. During aerobic respiration, which of the following directly donates electrons to the electron transport chain at the lowest energy level? A) NAD+ B) NADH C) ATP D) ADP + Pi E) FADH2

E

212. Photosynthesis is not responsible for A) oxygen in the atmosphere. B) the ozone layer. C) most of the organic carbon on Earth's surface. D) atmospheric CO2. E) fossil fuels

E

213. Which of the events listed below occurs in the light reactions of photosynthesis? A) NADP is produced. B) NADPH is reduced to NADP+. C) Carbon dioxide is incorporated into PGA. D) ATP is phosphorylated to yield ADP. E) Light is absorbed and funneled to reaction-center chlorophyll a.

E

216. What is the primary function of the Calvin cycle? A) use ATP to release carbon dioxide B) use NADPH to release carbon dioxide C) split water and release oxygen D) transport RuBP out of the chloroplast E) synthesize simple sugars from carbon dioxide

E

22.All of the following are part of a prokaryotic cell except A) DNA B) a cell wall C) a plasma membrane D) ribosome E) an endoplasmic reticulum

E

225. Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle? A) CO2 and glucose B) H2O and O2 C) ADP, P i, and NADP+ D) electrons and H+ E) ATP and NADPH

E

240. Which of the following is the first event to take place in translation in eukaryotes? A) elongation of the polypeptide B) base pairing of activated methionine-tRNA to AUG of the messenger RNA C) binding of the larger ribosomal subunit to smaller ribosomal subunits D) covalent bonding between the first two amino acids E) the small subunit of the ribosome recognizes and attaches to the 5' cap of mRNA

E

248. In comparing DNA replication with RNA transcription in the same cell, which of the following is true only of replication? A) It uses RNA polymerase. B) It makes a new molecule from its 5' end to its 3' end. C) The process is extremely fast once it is initiated. D) The process occurs in the nucleus of a eukaryotic cell. E) The entire template molecule is represented in the product.

E

161. A protein that spans the phospholipid bilayer one or more times is A) a transmembrane protein. B) an integral protein. C) a peripheral protein. D) an integrin. E) a glycoprotein

A

164. Which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly? A) CO2 B) an amino acid C) glucose D) K+ E) starch

A

104. Which of the following correctly describes chemical equilibrium? A) Forward and reverse reactions continue with no effect on the concentrations of the reactants and products. B) Concentrations of products are higher than the concentrations of the reactants. C) Forward and reverse reactions have stopped so that the concentration of the reactants equals the concentration of the products. D) Reactions stop only when all reactants have been converted to products.

A

110. A covalent bond is likely to be polar when A) one of the atoms sharing electrons is much more electronegative than the other atom. B) the two atoms sharing electrons are equally electronegative. C) oxygen is one of the two atoms sharing electrons. D) one of the atoms has absorbed more energy than the other atom. E) the two atoms sharing electrons are different elements

A

115. Electrons exist only at fixed levels of potential energy. However, if an atom absorbs sufficient energy, a possible result is that A) an electron may move to an electron shell farther away from the nucleus. B) an electron may move to an electron shell closer to the nucleus. C) the atom may become a radioactive isotope. D) the atom would become a positively charged ion, or cation, and become a radioactive isotope. E) the atom would become a negatively charged ion, or anion.

A

118. Which of these molecules is not formed by dehydration reactions? A) fatty acids B) disaccharides C) DNA D) protein E) amylose

A

120. Which of the following is not a polymer? A) glucose B) starch C) cellulose D) chitin E) DNA

A

121. Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? A) Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers. B) Dehydration reactions eliminate water from lipid membranes, and hydrolysis makes lipid membranes water permeable. C) Dehydration reactions can occur only after hydrolysis. D) Hydrolysis creates monomers, and dehydration reactions break down polymers. E) Dehydration reactions ionize water molecules and add hydroxyl groups to polymers; hydrolysis reactions release hydroxyl groups from polymers.

A

124. Which of the following is true of both starch and cellulose? A) They are both polymers of glucose. B) They are cis-trans isomers of each other. C) They can both be digested by humans. D) They are both used for energy storage in plants. E) They are both structural components of the plant cell wall.

A

128. Large organic molecules are usually assembled by polymerization of a few kinds of simple subunits. Which of the following is an exception to this statement? A) a steroid B) cellulose C) DNA D) an enzyme E) a contractile protein

A

133. Which bonds are created during the formation of the primary structure of a protein? A) peptide bonds B) hydrogen bonds C) disulfide bonds D) phosphodiester bonds E) peptide bonds, hydrogen bonds, and disulfide bonds

A

138. Which of the following can be determined directly from X-ray diffraction photographs of crystallized DNA? A) the diameter of the helix B) the rate of replication C) the sequence of nucleotides D) the bond angles of the subunits E) the frequency of A vs. T nucleotides

A

139. It became apparent to Watson and Crick after completion of their model that the DNA molecule could carry a vast amount of hereditary information in which of the following? A) sequence of bases B) phosphate-sugar backbones C) complementary pairing of bases D) side groups of nitrogenous bases E) different five-carbon sugars

A

143. The difference between ATP and the nucleoside triphosphates used during DNA synthesis is that A) the nucleoside triphosphates have the sugar deoxyribose; ATP has the sugar ribose. B) the nucleoside triphosphates have two phosphate groups; ATP has three phosphate groups. C) ATP contains three high-energy bonds; the nucleoside triphosphates have two. D) ATP is found only in human cells; the nucleoside triphosphates are found in all animal and plant cells. E) triphosphate monomers are active in the nucleoside triphosphates, but not in ATP

A

144. The leading and the lagging strands differ in that A) the leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction. B) the leading strand is synthesized by adding nucleotides to the 3' end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5' end. C) the lagging strand is synthesized continuously, whereas the leading strand is synthesized in short fragments that are ultimately stitched together. D) the leading strand is synthesized at twice the rate of the lagging strand.

A

145. Which of the following sets of materials are required by both eukaryotes and prokaryotes for replication? A) double-stranded DNA, four kinds of dNTPs, primers, origins B) topoisomerases, telomerases, polymerases C) G-C rich regions, polymerases, chromosome nicks D) nucleosome loosening, four dNTPs, four rNTPs E) ligase, primers, nucleases

A

146. What is the function of topoisomerase? A) relieving strain in the DNA ahead of the replication fork B) elongating new DNA at a replication fork by adding nucleotides to the existing chain C) adding methyl groups to bases of DNA D) unwinding of the double helix E) stabilizing single-stranded DNA at the replication fork

A

149. Why do histones bind tightly to DNA? A) Histones are positively charged, and DNA is negatively charged. B) Histones are negatively charged, and DNA is positively charged. C) Both histones and DNA are strongly hydrophobic. D) Histones are covalently linked to the DNA. E) Histones are highly hydrophobic, and DNA is hydrophilic

A

154. The spontaneous loss of amino groups from adenine in DNA results in hypoxanthine, an uncommon base, opposite thymine. What combination of proteins could repair such damage? A) nuclease, DNA polymerase, DNA ligase B) telomerase, primase, DNA polymerase C) telomerase, helicase, single-strand binding protein D) DNA ligase, replication fork proteins, adenylyl cyclase E) nuclease, telomerase, primase

A

185. Which of the following statements is true about enzyme-catalyzed reactions? A) The reaction is faster than the same reaction in the absence of the enzyme. B) The free energy change of the reaction is opposite from the reaction that occurs in the absence of the enzyme. C) The reaction always goes in the direction toward chemical equilibrium. D) Enzyme-catalyzed reactions require energy to activate the enzyme. E) Enzyme-catalyzed reactions release more free energy than noncatalyzed reactions.

A

190. Which of the following types of reactions would decrease the entropy within a cell? A) anabolic reactions B) hydrolysis C) respiration D) respiration E) catabolic reactions

A

196. When electrons move closer to a more electronegative atom, what happens? A) The more electronegative atom is reduced, and energy is released. B) The more electronegative atom is reduced, and energy is consumed. C) The more electronegative atom is oxidized, and energy is consumed. D) The more electronegative atom is oxidized, and energy is released. E) The more electronegative atom is reduced, and entropy decreases

A

197. Which of the following statements describes the results of this reaction?C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy A) C6H12O6 is oxidized and O2 is reduced. B) O2 is oxidized and H2O is reduced. C) CO2 is reduced and O2 is oxidized. D) C6H12O6 is reduced and CO2 is oxidized. E) O2 is reduced and CO2 is oxidized.

A

199. Which of the following statements describes NAD+? A) NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle. B) NAD+ has more chemical energy than NADH. C) NAD+ is oxidized by the action of hydrogenases. D) NAD+ can donate electrons for use in oxidative phosphorylation.

A

207. In prokaryotes, the respiratory electron transport chain is located A) in the plasma membrane. B) in the cytoplasm. C) in the bacterial outer membrane.

A

219. CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they A) fix CO2 into organic acids during the night. B) fix CO2 into sugars in the bundle-sheath cells. C) fix CO2 into pyruvate in the mesophyll cells. D) use the enzyme phosphofructokinase, which outcompetes rubisco for CO2. E) use photosystem I and photosystem II at night.

A

221. Compared to C3 plants, C4 plants A) can continue to fix CO2 even at relatively low CO2 concentrations and high oxygen concentrations. B) have higher rates of photorespiration. C) do not use rubisco for carbon fixation. D) grow better under cool, moist conditions. E) make a four-carbon compound, oxaloacetate, which is then delivered to the citric acid cycle in mitochondria.

A

226. Where does the Calvin cycle take place? A) stroma of the chloroplast B) thylakoid membrane C) cytoplasm surrounding the chloroplast D) interior of the thylakoid (thylakoid space) E) outer membrane of the chloroplast

A

231. Which of the following variations on translation would be most disadvantageous for a cell? A) translating polypeptides directly from DNA B) using fewer kinds of tRNA C) having only one stop codon D) lengthening the half-life of mRNA E) having a second codon (besides AUG) as a start codon

A

246. Gene expression in the domain Archaea in part resembles that of bacteria and in part that of the domain Eukarya. In which way is it most like the domain Eukarya? A) Domain Archaea have numerous transcription factors. B) Initiation of translation is like that of domain Eukarya. C) There is only one RNA polymerase. D) Transcription termination often involves attenuation. E) Post-transcriptional splicing is like that of Eukarya.

A

250. Which of the following is not true of RNA processing? A) Exons are cut out before mRNA leaves the nucleus. B) Nucleotides may be added at both ends of the RNA. C) Ribozymes may function in RNA splicing. D) RNA splicing can be catalyzed by spliceosomes. E) A primary transcript is often much longer than the final RNA molecule that leaves the nucleus.

A

103. An atom has 6 electrons in its outer shell. How many unpaired electrons does it have? A) 0 B) 2 C) 4 D) 6 E) 2 or 4

B

106. Van der Waals interactions result when A) hybrid orbitals overlap. B) electrons are not symmetrically distributed in a molecule. C) molecules held by ionic bonds react with water. D) two polar covalent bonds react. E) a hydrogen atom loses an electron.

B

113. What is the maximum number of electrons in a single 2 p orbital of an atom? A) 1 B) 2 C) 3 D) 4 E) 5

B

119. Which of these classes of biological molecules consist of both small molecules and macromolecular polymers? A) lipids B) carbohydrates C) proteins D) nucleic acids E) lipids,carbohydrates, protein, and nucleic acids all consist of only macromolecular polymers

B

122. The molecular formula for glucose is C6H12O6. What would be the molecular formula for a molecule made by linking three glucose molecules together by dehydration reactions? A) C18H36O18 B) C18H32O16 C) C6H10O5 D) C18H10O15 E) C3H6O3

B

126. Which of the following statements concerning saturated fats is not true? A) They are more common in animals than in plants. B) They have multiple double bonds in the carbon chains of their fatty acids. C) They generally solidify at room temperature. D) They contain more hydrogen than unsaturated fats having the same number of carbon atoms. E) They are one of several factors that contribute to atherosclerosis

B

127. A molecule with the formula C18H36O2 is probably a A) carbohydrate B) fatty acid C) protein D) nucleic acid E) hydrocarbon

B

129. All of the following contain amino acids except A) hemoglobin. B) cholesterol. C) antibodies. D) enzymes. E) insulin.

B

131. Polysaccharides, triacylglycerides, and proteins are similar in that they A) are synthesized from monomers by the process of hydrolysis. B) are synthesized from subunits by dehydration reactions. C) are synthesized as a result of peptide bond formation between monomers. D) are decomposed into their subunits by dehydration reactions. E) all contain nitrogen in their monomer building blocks.

B

134. Which level of protein structure do the α helix and the β pleated sheet represent? A) primary B) secondary C) tertiary D) quaternary E) primary, secondary, tertiary, and quaternary

B

135. Which of the following statements about the 5' end of a polynucleotide strand of DNA is correct? A) The 5' end has a hydroxyl group attached to the number 5 carbon of ribose. B) The 5' end has a phosphate group attached to the number 5 carbon of ribose. C) The 5' end has phosphate attached to the number 5 carbon of the nitrogenous base. D) The 5' end has a carboxyl group attached to the number 5 carbon of ribose. E) The 5' end is the fifth position on one of the nitrogenous bases.

B

137. In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of which of the following facts? A) DNA contains sulfur, whereas protein does not. B) DNA contains phosphorus, whereas protein does not. C) DNA contains nitrogen, whereas protein does not. D) DNA contains purines, whereas protein includes pyrimidines. E) RNA includes ribose, whereas DNA includes deoxyribose sugars.

B

141. Replication in prokaryotes differs from replication in eukaryotes for which of the following reasons? A) Prokaryotic chromosomes have histones, whereas eukaryotic chromosomes do not. B) Prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have many. C) The rate of elongation during DNA replication is slower in prokaryotes than in eukaryotes. D) Prokaryotes produce Okazaki fragments during DNA replication, but eukaryotes do not. E) Prokaryotes have telomeres, and eukaryotes do not.

B

142. What is meant by the description "antiparallel" regarding the strands that make up DNA? A) The twisting nature of DNA creates nonparallel strands. B) The 5' to 3' direction of one strand runs counter to the 5' to 3' direction of the other strand. C) Base pairings create unequal spacing between the two DNA strands. D) One strand is positively charged and the other is negatively charged. E) One strand contains only purines and the other contains only pyrimidines.

B

148. Which of the following statements is true of histones? A) Each nucleosome consists of two molecules of histone H1. B) Histone H1 is not present in the nucleosome bead; instead, it draws the nucleosomes together. C) The carboxyl end of each histone extends outward from the nucleosome and is called a "histone tail." D) Histones are found in mammals, but not in other animals or in plants or fungi. E) The mass of histone in chromatin is approximately nine times the mass of DNA.

B

155. In his transformation experiments, what did Griffith observe? A) Mutant mice were resistant to bacterial infections. B) Mixing a heat-killed pathogenic strain of bacteria with a living nonpathogenic strain can convert some of the living cells into the pathogenic form. C) Mixing a heat-killed nonpathogenic strain of bacteria with a living pathogenic strain makes the pathogenic strain nonpathogenic. D) Infecting mice with nonpathogenic strains of bacteria makes them resistant to pathogenic strains. E) Mice infected with a pathogenic strain of bacteria can spread the infection to other mice.

B

163. What kinds of molecules pass through a cell membrane most easily? A) large and hydrophobic B) small and hydrophobic C) large polar D) ionic E) monosaccharides such as glucose

B

173. A bacterium engulfed by a white blood cell through phagocytosis will be digested by enzymes contained in A) peroxisomes. B) lysosomes. C) Golgi vesicles. D) vacuoles. E) secretory vesicles.

B

182. Why is ATP an important molecule in metabolism? A) Its hydrolysis provides an input of free energy for exergonic reactions. B) It provides energy coupling between exergonic and endergonic reactions. C) Its terminal phosphate group contains a strong covalent bond that, when hydrolyzed, releases free energy. D) Its terminal phosphate bond has higher energy than the other two. E) It is one of the four building blocks for DNA synthesis.

B

184. Which of the following statements is true concerning catabolic pathways? A) They combine molecules into more energy-rich molecules. B) They supply energy, primarily in the form of ATP, for the cell's work. C) They are endergonic. D) They are spontaneous and do not need enzyme catalysis. E) They build up complex molecules such as protein from simpler compounds.

B

186. The mechanism in which the end product of a metabolic pathway inhibits an earlier step in the pathway is most precisely described as A) metabolic inhibition. B) feedback inhibition. C) allosteric inhibition. D) noncooperative inhibition. E) reversible inhibition.

B

187. Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism as ________ is to ________. A) exergonic; spontaneous B) exergonic; endergonic C) free energy; entropy D) work; energy E) entropy; enthalpy

B

188. Which of the following metabolic processes can occur without a net influx of energy from some other process? A) ADP + P i → ATP + H2O B) C6H12O6 + 6 O2 → 6 CO2 + 6 H2O C) 6 CO2 + 6 H2O → C6H12O6 + 6 O2 D) amino acids → protein E) glucose + fructose → sucrose

B

193.Which of the following best describes enthalpy (H)? A) the total kinetic energy of a system B) the heat content of a chemical system C) the system's entropy D) the cell's energy equilibrium E) the condition of a cell that is not able to react

B

194. What is the term for metabolic pathways that release stored energy by breaking down complex molecules? A) anabolic pathways B) catabolic pathways C) fermentation pathways D) thermodynamic pathways E) bioenergetic pathways

B

195. The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction A) gains electrons and gains potential energy. B) loses electrons and loses potential energy. C) gains electrons and loses potential energy. D) loses electrons and gains potential energy. E) neither gains nor loses electrons, but gains or loses potential energy.

B

201. In glycolysis, for each molecule of glucose oxidized to pyruvate A) two molecules of ATP are used and two molecules of ATP are produced. B) two molecules of ATP are used and four molecules of ATP are produced. C) four molecules of ATP are used and two molecules of ATP are produced. D) two molecules of ATP are used and six molecules of ATP are produced. E) six molecules of ATP are used and six molecules of ATP are produced.

B

202. In cellular respiration, the energy for most ATP synthesis is supplied by A) high energy phosphate bonds in organic molecules. B) a proton gradient across a membrane. C) converting oxygen to ATP. D) transferring electrons from organic molecules to pyruvate. E) generating carbon dioxide and oxygen in the electron transport chain.

B

204. The primary role of oxygen in cellular respiration is to A) yield energy in the form of ATP as it is passed down the respiratory chain. B) act as an acceptor for electrons and hydrogen, forming water. C) combine with carbon, forming CO2.

B

209. One function of both alcohol fermentation and lactic acid fermentation is to A) reduce FADH2 to FAD+. B) oxidize NADH to NAD+. C) reduce FAD+ to FADH2.

B

215. Which of the following statements best describes the relationship between photosynthesis and respiration? A) Respiration runs the biochemical pathways of photosynthesis in reverse. B) Photosynthesis stores energy in complex organic molecules, whereas respiration releases it. C) Photosynthesis occurs only in plants and respiration occurs only in animals. D) ATP molecules are produced in photosynthesis and used up in respiration. E) Respiration is anabolic and photosynthesis is catabolic.

B

217. In C3 photosynthesis, the reactions that require ATP take place in A) the light reactions alone. B) the Calvin cycle alone. C) both the light reactions and the Calvin cycle. D) neither the light reactions nor the Calvin cycle. E) the chloroplast, but is not part of photosynthesis.

B

218. Why are C4 plants able to photosynthesize with no apparent photorespiration? A) They do not participate in the Calvin cycle. B) They use PEP carboxylase to initially fix CO2. C) They are adapted to cold, wet climates. D) They conserve water more efficiently. E) They exclude oxygen from their tissues.

B

235. Which of the following statements best describes the termination of transcription in prokaryotes? A) RNA polymerase transcribes through the polyadenylation signal, causing proteins to associate with the transcript and cut it free from the polymerase. B) RNA polymerase transcribes through the terminator sequence, causing the polymerase to separate from the DNA and release the transcript. C) RNA polymerase transcribes through an intron, and the snRNPs cause the polymerase to let go of the transcript. D) Once transcription has initiated, RNA polymerase transcribes until it reaches the end of the chromosome. E) RNA polymerase transcribes through a stop codon, causing the polymerase to stop advancing through the gene and release the mRNA.

B

238. What is a ribozyme? A) an enzyme that uses RNA as a substrate B) an RNA with enzymatic activity C) an enzyme that catalyzes the association between the large and small ribosomal subunits D) an enzyme that synthesizes RNA as part of the transcription process E) an enzyme that synthesizes RNA primers during DNA replication

B

242. The process of translation, whether in prokaryotes or eukaryotes, requires tRNAs, amino acids, ribosomal subunits, and which of the following? A) polypeptide factors plus ATP B) polypeptide factors plus GTP C) polymerases plus GTP D) SRP plus chaperones E) signal peptides plus release factor

B

245. Which of the following statements is true about protein synthesis in prokaryotes? A) Extensive RNA processing is required before prokaryotic transcripts can be translated. B) Translation can begin while transcription is still in progress. C) Prokaryotic cells have complicated mechanisms for targeting proteins to the appropriate cellular organelles. D) Translation requires antibiotic activity. E) Unlike eukaryotes, prokaryotes require no initiation or elongation factors.

B

249. Which component is not directly involved in translation? A) mRNA B) DNA C) tRNA D) ribosomes E) GTP

B

125. Humans can digest starch but not cellulose because A) the monomer of starch is glucose, while the monomer of cellulose is galactose. B) humans have enzymes that can hydrolyze the β glycosidic linkages of starch but not the α glycosidic linkages of cellulose. C) humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose. D) humans harbor starch-digesting bacteria in the digestive tract. E) the monomer of starch is glucose, while the monomer of cellulose is glucose with a nitrogen-containing group.

C

130. There are 20 different amino acids. What makes one amino acid different from another? A) different side chains (R groups) attached to a carboxyl carbon B) different side chains (R groups) attached to the amino groups C) different side chains (R groups) attached to an α carbon D) different structural and optical isomers E) different asymmetric carbons

C

140. In an analysis of the nucleotide composition of DNA, which of the following will be found? A) A = C B) A = G and C = T C) A + C = G + T D) G + C = T + A

C

150. Which of the following statements describes chromatin? A) Heterochromatin is composed of DNA, whereas euchromatin is made of DNA and RNA. B) Both heterochromatin and euchromatin are found in the cytoplasm. C) Heterochromatin is highly condensed, whereas euchromatin is less compact. D) Euchromatin is not transcribed, whereas heterochromatin is transcribed. E) Only euchromatin is visible under the light microscope.

C

151. What is the basis for the difference in how the leading and lagging strands of DNA molecules are synthesized? A) The origins of replication occur only at the 5' end. B) Helicases and single-strand binding proteins work at the 5' end. C) DNA polymerase can join new nucleotides only to the 3' end of a growing strand. D) DNA ligase works only in the 3' → 5' direction. E) Polymerase can work on only one strand at a time.

C

153. In a nucleosome, the DNA is wrapped around A) polymerase molecules. B) ribosomes. C) histones. D) a thymine dimer. E) satellite DNA.

C

158. Which of the following types of molecules are the major structural components of the cell membrane? A) phospholipids and cellulose B) nucleic acids and proteins C) phospholipids and proteins D) proteins and cellulose E) glycoproteins and cholesterol

C

159. In order for a protein to be an integral membrane protein it would have to be A) hydrophilic. B) hydrophobic. C) amphipathic, with at least one hydrophobic region. D) completely covered with phospholipids. E) exposed on only one surface of the membrane

C

160. Which of the following is true of integral membrane proteins? A) They lack tertiary structure. B) They are loosely bound to the surface of the bilayer. C) They are usually transmembrane proteins. D) They are not mobile within the bilayer. E) They serve only a structural role in membranes.

C

165. Which of the following statements is correct about diffusion? A) It is very rapid over long distances. B) It requires an expenditure of energy by the cell. C) It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration. D) It is an active process in which molecules move from a region of lower concentration to one of higher concentration. E) It requires integral proteins in the cell membrane.

C

167. Which of the following membrane activities require energy from ATP hydrolysis? A) facilitated diffusion of chloride ions across the membrane through a chloride channel B) movement of water into a cell C) Na+ ions moving out of a mammalian cell bathed in physiological saline D) movement of glucose molecules into a bacterial cell from a medium containing a higher concentration of glucose than inside the cell E) movement of carbon dioxide out of a paramecium

C

169. What is the voltage across a membrane called? A) water potential B) chemical gradient C) membrane potential D) osmotic potential E) electrochemical gradient

C

170. The sodium-potassium pump is called an electrogenic pump because it A) pumps equal quantities of Na+ and K+ across the membrane. B) pumps hydrogen ions out of the cell. C) contributes to the membrane potential. D) ionizes sodium and potassium atoms. E) is used to drive the transport of other molecules against a concentration gradient.

C

174. The movement of potassium into an animal cell requires A) low cellular concentrations of sodium. B) high cellular concentrations of potassium. C) an energy source such as ATP. D) a cotransport protein. E) potassium channel protein

C

176. Which of the following is (are) true for anabolic pathways? A) They do not depend on enzymes. B) They are usually highly spontaneous chemical reactions. C) They consume energy to build up polymers from monomers. D) They release energy as they degrade polymers to monomers. E) They consume energy to decrease the entropy of the organism and its environment.

C

183. Which of the following is most similar in structure to ATP? A) a pentose sugar B) a DNA nucleotide C) an RNA nucleotide D) an amino acid with three phosphate groups attached E) a phospholipid

C

12.What are archaea? A) prokaryotes characterized as extremophiles that share some bacterial and some eukaryotic traits B) organisms that are adapted to high temperature environments, such as in volcanic springs C) single-celled organisms that are killed by the application of antibiotics at certain concentrations D) bacteria-like organisms that can live only in extreme salt environments E) primitive protist-like creatures possessing fewer than two chromosomes per cell

A

26.Which structure is the site of the synthesis of proteins that may be exported from the cell? A) rough ER B) lysosomes C) plasmodesmata D) Golgi vesicles E) free cytoplasmic ribosomes

A

3.The main source of energy for producers in an ecosystem is A) light energy B) kinetic energy C) thermal energy D) chemical energy E) ATP

A

39.Cells require which of the following to form cilia or flagella? A) centrosomes B) laminin C) actin D) intermediate filaments E) secretory vesicles

A

40.Movement of vesicles within the cell depends on what cellular structures? A) microtubules and motor proteins B) actin filaments and microtubules C) actin filaments and ribosomes D) centrioles and motor proteins E) actin filaments and motor proteins

A

41. The centromere is a region in which A) chromatids remain attached to one another until anaphase. B) metaphase chromosomes become aligned at the metaphase plate. C) chromosomes are grouped during telophase. D) the nucleus is located prior to mitosis. E) new spindle microtubules form at either end

A

42.If there are 20 chromatids in a cell, how many centromeres are there? A) 10 B) 20 C) 30 D) 40 E) 80

A

47.A particular cell has half as much DNA as some other cells in a mitotically active tissue. The cell in question is most likely in A) G1. B) G2. C) prophase. D) metaphase. E) anaphase.

A

53.The MPF protein complex turns itself off by A) activating a process that destroys cyclin components. B) activating an enzyme that stimulates cyclin. C) binding to chromatin. D) exiting the cell. E) activating the anaphase-promoting complex.

A

61.The human genome is minimally contained in which of the following? A) every human cell B) each human chromosome C) the entire DNA of a single human D) the entire human population E) each human gene

A

62.In the human species, all somatic cells have 46 chromosomes. Which of the following can also be true? A) A plant species (privet shrubs) has 46 chromosomes per cell. B) Some adult humans have 69 chromosomes per cell. C) Some adult humans have 23 chromosomes per cell. D) A certain fungal species has only one chromosome per cell. E) A certain bacterial species has 23 chromosomes.

A

84. Which of the following differentiates between independent assortment and segregation? A) The law of independent assortment requires describing two or more genes relative to one another. B) The law of segregation requires describing two or more genes relative to one another. C) The law of segregation requires having two or more generations to describe. D) The law of independent assortment is accounted for by observations of prophase I. E) The law of segregation is accounted for by anaphase of mitosis.

A

10.What is the major difference between a kingdom and a domain? A) a kingdom can include several subgroups known as domains B) all eukarya belong to one domain C) all prokaryotes belong to one domain D) the importance of fungi has led scientists to make them the whole of one domain E) only organisms that produce their own food belong to one of the domains

B

18.A water sample from a hot thermal vent contained a single-celled organism that had a cell but lacked a nucleus. What is its mostly likely classification? A) Eukarya B) Archaea C) Animalia D) Protista E) Fungi

B

23.Prokaryotes are classified as belonging to two different domains. What are the domains? A) Bacteria and Eukarya B) Bacteria and Archaea C) Archaea and Protista D) Bacteria and Protista E) Bacteria and Fungi

B

28.Which organelle often takes up much of the volume of a plant cell? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

B

32.Thylakoids, DNA, and ribosomes are all components found in A) vacuoles B) chloroplasts C) mitochondria D) lysosomes E) nuclei

B

44.Where do the microtubules of the spindle originate during mitosis in both plant and animal cells? A) centromere B) centrosome C) centriole D) chromatid E) kinetochore

B

48.Which of the following does not occur during mitosis? A) condensation of the chromosomes B) replication of the DNA C) separation of sister chromatids D) spindle formation E) cell cycles lacking an S phase.

B

50.Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely A) an animal cell in the process of cytokinesis. B) a plant cell in the process of cytokinesis. C) an animal cell in the S phase of the cell cycle. D) a bacterial cell dividing. E) a plant cell in metaphase.

B

51.Which of the following triggers the cell's passage past the G2 checkpoint into mitosis? A) PDGF B) MPF C) protein kinase D) cyclin E) Cdk

B

58.Which of the following are primarily responsible for cytokinesis in plant cells but not in animal cells? A) kinetochores B) Golgi-derived vesicles C) actin and myosin D) centrioles and centromeres E) cyclin-dependent kinases

B

59.Why do chromosomes coil during mitosis? A) to increase their potential energy B) to allow the chromosomes to move without becoming entangled and breaking C) to allow the chromosomes to fit within the nuclear envelope D) to allow the sister chromatids to remain attached E) to provide for the structure of the centromere

B

63.Which of the following is a true statement about sexual vs. asexual reproduction? A) Asexual reproduction, but not sexual reproduction, is characteristic of plants and fungi. B) In sexual reproduction, individuals transmit 50% of their genes to each of their offspring. C) In asexual reproduction, offspring are produced by fertilization without meiosis. D) Sexual reproduction requires that parents be diploid. E) Asexual reproduction produces only haploid offspring.

B

65.At which stage of mitosis are chromosomes usually photographed in the preparation of a karyotype? A) prophase B) metaphase C) anaphase D) telophase E) interphase

B

67.Referring to a plant's sexual life cycle, which of the following terms describes the process that leads directly to the formation of gametes? A) sporophyte meiosis B) gametophyte mitosis C) gametophyte meiosis D) sporophyte mitosis E) alternation of generations

B

68.Which of the following best describes a karyotype? A) a pictorial representation of all the genes for a species B) a display of each of the chromosomes of a single cell C) the combination of all the maternal and paternal chromosomes of a species D) the collection of all the chromosomes in an individual organism E) a photograph of all the cells with missing or extra chromosomes

B

71.Which of the following occurs in meiosis but not in mitosis? A) chromosome replication B) synapsis of chromosomes C) production of daughter cells D) alignment of chromosomes at the equator E) condensation of chromatin

B

73.Homologous chromosomes move toward opposite poles of a dividing cell during A) mitosis. B) meiosis I. C) meiosis II. D) fertilization. E) binary fission

B

75.Independent assortment of chromosomes occurs. A) The statement is true for mitosis only. B) The statement is true for meiosis I only. C) The statement is true for meiosis II only. D) The statement is true for mitosis and meiosis I. E) The statement is true for mitosis and meiosis II.

B

76.A cell divides to produce two daughter cells that are genetically different. A) The statement is true for mitosis only. B) The statement is true for meiosis I only. C) The statement is true for meiosis II only. D) The statement is true for mitosis and meiosis I. E) The statement is true for mitosis and meiosis II

B

14.System biology is mainly an attempt to A) analyze genomes from different species B) simplify complex problems by reducing the system into smaller, less complex units C) understand the behavior of entire biological systems D) build high-thoughput machines from the rapid acquisition of biological data E) speed up the technological application of scientific knowledge

C

15.Protists and bacteria are grouped into different domains because A) protists eat bacteria B) bacteria are not made of cells C) protists have a membrane-bounded nucleus, which bacterial cells lack D) bacteria decompose protists E) protists are photosynthetic

C

16.Which of the following best demonstrates the unity among all organisms? A) matching DNA nucleotide sequences B) descent with modification C) the structure and function of DNA D) natural selection E) emergent properties

C

17.Organisms interact with their environments, exchanging matter and energy. For examples, plant chloroplasts convert the energy of sunlight into A) the energy of motion B) carbon dioxide and water C) the potential energy of chemical bonds D) oxygen E) kinetic energy

C

30.Which plant cell organelle contains its own DNA and ribosomes? A) glyoxysome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

C

34.A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from A) a bacterium B) an animal, but not a plant C) nearly any eukaryotic organism D) any multicellular organism, like a plant or an animal E) any kind of organism

C

37.Signals between the ECM and the cytoskeleton may be transmitted by A) fibronectin. B) proteoglycans. C) integrins. D) collagen. E) middle lamella.

C

46.For anaphase to begin, which of the following must occur? A) Chromatids must lose their kinetochores. B) Cohesin must attach the sister chromatids to each other. C) Cohesin must be cleaved enzymatically. D) Kinetochores must attach to the metaphase plate. E) Spindle microtubules must begin to depolymerize.

C

49.One difference between cancer cells and normal cells is that cancer cells A) are unable to synthesize DNA. B) are arrested at the S phase of the cell cycle. C) continue to divide even when they are tightly packed together. D) cannot function properly because they are affected by density-dependent inhibition. E) are always in the M phase of the cell cycle

C

5.Which branch of biology is concerned with the naming and classifying of organisms? A) informatics B) schematic biology C) taxonomy D) genomics E) evolution

C

55.Besides the ability of some cancer cells to overproliferate, what else could logically result in a tumor? A) metastasis B) changes in the order of cell cycle stages C) lack of appropriate cell death D) inability to form spindles E) inability of chromosomes to meet at the metaphase plate

C

7.Prokaryotic and eukaryotic cells general have which of the following features in common? A) a membrane-bounded nucleus B) a cell wall made of cellulose C) ribosomes D) flagella or cilia that contain microtubules E) linear chromosomes made of DNA and protein

C

8.Which of the following types of cells utilize DNA as their genetic material but do not have their DNA encased within a nuclear envelope? A) animal B) plant C) archaea D) fungi E) protists

C

80.A karyotype results from which of the following? A) a natural cellular arrangement of chromosomes in the nucleus B) an inherited ability of chromosomes to arrange themselves C) the ordering of human chromosome images D) the cutting and pasting of parts of chromosomes to form the standard array E) the separation of homologous chromosomes at metaphase I of meiosis

C

81. What do we mean when we use the terms monohybrid cross and dihybrid cross? A) A monohybrid cross involves a single parent, whereas a dihybrid cross involves two parents. B) A monohybrid cross produces a single progeny, whereas a dihybrid cross produces two progeny. C) A dihybrid cross involves organisms that are heterozygous for two characters and a monohybrid cross involves only one. D) A monohybrid cross is performed for one generation, whereas a dihybrid cross is performed for two generations. E) A monohybrid cross results in a 9:3:3:1 ratio whereas a dihybrid cross gives a 3:1 ratio.

C

86. When crossing an organism that is homozygous recessive for a single trait with a heterozygote, what is the chance of producing an offspring with the homozygous recessive phenotype? A) 0% B) 25% C) 50% D) 75% E) 100%

C

87. Mendel's second law of independent assortment has its basis in which of the following events of meiosis I? A) synapsis of homologous chromosomes B) crossing over C) alignment of tetrads at the equator D) separation of homologs at anaphase E) separation of cells at telophase

C

88. Which of the following describes the ability of a single gene to have multiple phenotypic effects? A) incomplete dominance B) multiple alleles C) pleiotropy D) epistasis

C

97. Which of the following statements is false? A) Carbon, hydrogen, oxygen, and nitrogen are the most abundant elements of living matter. B) Some trace elements are very abundant on Earth. C) Virtually all organisms require the same elements in the same quantities. D) Iron is an example of an element needed by all organisms. E) Other than some trace elements, animals are mostly made up of the same elements as plants, in similar proportions.

C

99. Why is each element unique and different from other elements in chemical properties? A) Each element has a unique atomic mass. B) Each element has a unique atomic weight. C) Each element has a unique number of protons in its nucleus. D) Each element has a unique number of neutrons in its nucleus. E) Each element has different radioactive properties.

C

36.A biologist ground up some plant leaf cells and then centrifuged the mixture to fractionate the organelles. Organelles in one of the heavier fractions could produce ATP in the light, whereas organelles in the lighter fraction could produce ATP in the dark. The heavier and lighter fractions are most likely to contain, respectively, A) mitochondria and chloroplasts. B) chloroplasts and peroxisomes. C) peroxisomes and chloroplasts. D) chloroplasts and mitochondria. E) mitochondria and peroxisomes.

D

38.The cell walls of bacteria, fungi, and plant cells and the extracellular matrix of animal cells are all external to the plasma membrane. Which of the following is a characteristic common to all of these extracellular structures? A) They must block water and small molecules in order to regulate the exchange of matter and energy with their environment. B) They must permit information transfer between the cell's cytoplasm and the nucleus. C) They must provide a rigid structure that maintains an appropriate ratio of cell surface area to volume. D) They are constructed of polymers that are synthesized in the cytoplasm and then transported out of the cell. E) They are composed of a mixture of lipids and carbohydrates.

D

57.Suppose a biologist can separate one of a dozen pieces of chromatin from a eukaryotic (animal) nucleus. It might consist of which of the following? A) one-twelfth of the genes of the organism B) two chromosomes, each with six chromatids C) a single circular piece of DNA D) two long strands of DNA plus proteins E) two chromatids attached together at a centromere

D

6.Through time, the lineage that led to modern whales shows a change from four-limbed land animals to aquatic animals with two limbs that function as flippers. This change is best explained by A) natural philosophy B) creationism C) the hierarchy of the biological organization of life D) natural selection E) feedback inhibition

D

60.Which of the following best describes how chromosomes move toward the poles of the spindle during mitosis? A) The chromosomes are "reeled in" by the contraction of spindle microtubules. B) Motor proteins of the kinetochores move the chromosomes along the spindle microtubules. C) Nonkinetochore spindle fibers serve to push chromosomes in the direction of the poles. D) The chromosomes are "reeled in" by the contraction of spindle microtubules, and motor proteins of the kinetochores move the chromosomes along the spindle microtubules. E) The chromosomes are "reeled in" by the contraction of spindle microtubules, motor proteins of the kinetochores move the chromosomes along the spindle microtubules, and nonkinetochore spindle fibers serve to push chromosomes in the direction of the poles.

D

66.The human X and Y chromosomes A) are both present in every somatic cell of males and females alike. B) are of approximately equal size and number of genes. C) are almost entirely homologous, despite their different names. D) include genes that determine an individual's sex. E) include only genes that govern sex determination.

D

77.How do cells at the completion of meiosis compare with cells that have replicated their DNA and are just about to begin meiosis? A) They have twice the amount of cytoplasm and half the amount of DNA. B) They have half the number of chromosomes and half the amount of DNA. C) They have the same number of chromosomes and half the amount of DNA. D) They have half the number of chromosomes and one-fourth the amount of DNA. E) They have half the amount of cytoplasm and twice the amount of DNA.

D

78.After telophase I of meiosis, the chromosomal makeup of each daughter cell is A) diploid, and the chromosomes are each composed of a single chromatid. B) diploid, and the chromosomes are each composed of two chromatids. C) haploid, and the chromosomes are each composed of a single chromatid. D) haploid, and the chromosomes are each composed of two chromatids. E) tetraploid, and the chromosomes are each composed of two chromatids.

D

79.Which of the following can utilize both mitosis and meiosis in the correct circumstances? A) a haploid animal cell B) a diploid cell from a plant stem C) any diploid animal cell D) a plantlike protist E) an archaebacterium

D

82. Why did the F1 offspring of Mendel's classic pea cross always look like one of the two parental varieties? A) No genes interacted to produce the parental phenotype. B) Each allele affected phenotypic expression. C) The traits blended together during fertilization. D) One phenotype was completely dominant over another. E) Different genes interacted to produce the parental phenotype.

D

89. Most genes have many more than two alleles. However, which of the following is also true? A) At least one allele for a gene always produces a dominant phenotype. B) Most of the alleles will never be found in a live-born organism. C) All of the alleles but one will produce harmful effects if homozygous. D) There may still be only two phenotypes for the trait. E) More than two alleles in a genotype is considered lethal

D

93. )Radish flowers may be red, purple, or white. A cross between a red-flowered plant and a white-flowered plant yields all-purple offspring. The part of the radish we eat may be oval or long, with long being the dominant characteristic. QUESTION: If true-breeding red long radishes are crossed with true-breeding white oval radishes, the F1 will be expected to be which of the following? A) red and long B) red and oval C) white and long D) purple and long E) purple and oval

D

95) Radish flowers may be red, purple, or white. A cross between a red-flowered plant and a white-flowered plant yields all-purple offspring. The part of the radish we eat may be oval or long, with long being the dominant characteristic. The flower color trait in radishes is an example of which of the following? A) a multiple allelic system B) sex linkage C) codominance D) incomplete dominance E) epistasis

D

96. About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter? A) carbon, sodium, hydrogen, nitrogen B) carbon, oxygen, phosphorus, hydrogen C) oxygen, hydrogen, calcium, nitrogen D) carbon, hydrogen, nitrogen, oxygen E) carbon, oxygen, nitrogen, calcium

D

1. Which of the following sequences represents the hierarchy of biological organization from the least to the most complex level? A) ecosystem, cell population, tissue, organism, organ system B) organism, community, biosphere, molecule, tissue, organ C) organelle, tissue, biosphere, ecosystem, population, organism D) cell, community, population, organ system, molecule, organelle E) molecule, cell, organ system, population, ecosystem, biosphere

E

31.Which animal cell organelle contains enzymes that transfer hydrogen from various substrates to oxygen? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

E

4.Prokaryotes are classified as belonging to two different domains. What are the domains? A) Bacteria and Eukarya B) Archaea and Monera C) Eukarya and Monera D) Bacteria and Protista E) Bacteria and Archaea `

E

43.At which phase are centrioles beginning to move apart in animal cells? A) telophase B) anaphase C) prometaphase D) metaphase E) prophase

E

52.The cyclin component of MPF is destroyed toward the end of which phase? A) G0 B) G1 C) S D) G2 E) M

E

54.A mutation results in a cell that no longer produces a normal protein kinase for the M phase checkpoint. Which of the following would likely be the immediate result of this mutation? A) The cell would prematurely enter anaphase. B) The cell would never leave metaphase. C) The cell would never enter metaphase. D) The cell would never enter prophase. E) The cell would undergo normal mitosis, but fail to enter the next G1 phase.

E

64.Which of the following defines a genome? A) representation of a complete set of a cell's polypeptides B) the complete set of an organism's polypeptides C) the complete set of a species' polypeptides D) a karyotype E) the complete set of an organism's genes

E

70.Chromatids are separated from each other. A) The statement is true for mitosis only. B) The statement is true for meiosis I only. C) The statement is true for meiosis II only. D) The statement is true for mitosis and meiosis I. E) The statement is true for mitosis and meiosis II.

E

9.Which of the following is(are) true of natural selection? A) it requires genetic variation B) it results in descent with modification C) it involves differential reproductive success D) it results in descent with modification and involves differential reproductive success E) it requires genetic variation, results in descent with modification, and involves differential reproductive success

E

90. Which of the following is an example of polygenic inheritance? A) pink flowers in snapdragons B) the ABO blood group in humans C) Huntington's disease in humans D) white and purple flower color in peas E) skin pigmentation in humans

E

91. Labrador retrievers are black, brown, or yellow. In a cross of a black female with a brown male, results can be either all black puppies, 1/2 black to 1/2 brown puppies, or 3/4 black to 1/4 yellow puppies. QUESTION: These results indicate which of the following? A) Brown is dominant to black. B) Black is dominant to brown and to yellow. C) Yellow is dominant to black. D) There is incomplete dominance. E) Epistasis is involved.

E

94) Radish flowers may be red, purple, or white. A cross between a red-flowered plant and a white-flowered plant yields all-purple offspring. The part of the radish we eat may be oval or long, with long being the dominant characteristic. In the F2 generation of the above cross, which of the following phenotypic ratios would be expected? A) 9:3:3:1 B) 9:4:3 C) 1:1:1:1 D) 1:1:1:1:1:1 E) 6:3:3:2:1:1

E

98. What factors are most important in determining which elements are most common in living matter? A) the relative abundances of the elements in Earth's crust and atmosphere B) the emergent properties of the simple compounds made from these elements C) the reactivity of the elements with water D) the chemical stability of the elements E) both the relative abundances of the elements and the emergent properties of the compounds made from these elements

E


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