A.P. Biology Bowl Answer Bank 1. Many biologists think that a phylogenetic relationship exists between annelid worms and mollusks because both animals W. possess a segmented body X. Possess a centrally located visceral mass Y. Feature a ciliated larva called a trochophore in their life cycles * Z. Display cephalization 2. Which of the following functional groups represents a product of fermentation W. Carbonyl group C=O X. Hydroxyl group –OH * Y. Sulfhydryl group S-H Z. Carboxyl group -COOH 3. The rise of water in a plant stem is due primarily to W. Hydrotropism and companion cells X. Photolysis and chemiosmosis Y. Turgor pressure and membrane potential Z. Cohesion and transpiration* 4. Which of the following correctly describes retroviruses? W. They reproduce only in the cells of epithelial tissue X. They transfer genetic information from the RNA to the DNA of the cell* Y. They lack the enzyme reverse transcriptase Z. They transfer genetic information from their RNA to the ribosome in a cell 5. Some taxonomists have proposed adding a new taxon to the modern system of of biological classification that includes viruses. The inclusion of the new taxon is based on W. The chemical nature of the capsids X. Similarities in RNA nucleotides * Y. Differences in glycoproteins that envelop capsids Z. Their ability to alternate between hosts species 6. A hormone involved in digestion is W. Cholecystokinin * X. Enterokinase Y. Vasopressin Z. Enkephalin 7. Dolly, the cloned sheep, originated as a nucleus that was removed from an udder cell of a ewe an transplanted into W. The uterus of a surrogate ewe X. The ovum of a surrogate ewe Y. The enucleated ovum of a second ewe * Z. A blastocyst in vitro, and then transplanted into the uterus of a surrogate ewe 8. Which pair is actively involved in prothrombin production? W. Calcium ions and lipoproteins X. Ferrous ions and erythopoeitin Y. Kuppfer cells and thrombocytes Z. Vitamin K and colon bacteria * 9. Which organism has the highest reproductive rate as a result of its hermaphroditism? W. Bread mold X. Cycad tree Y. Earthworm * Z. Sea star 10. Which pair of animals occupy the same ecological niche, and are therefore called ecological equivalents? W. Zooplankton and trout X. Zebra and wild horse * Y. Rattlesnake and scorpion Z. Tiger and warthog 11. The part of a plant’s vascular system that uses companion cells to transfer nutrients to different parts of the plant is called the W. Xylem X. Phloem* Y. Tracheids Z. Casparian strip 12. The plant hormone, abscissic acid, mainly influences W. Growth of stems and root tips* X. Production of ethylene gas Y. Aging of leaves Z. Regulation of turgor pressure by causing water to leave guard cells 13. The probable reasons for the low numbers of dead bacteria during the first 13 hour period are W. An adequate amount of oxygen and nutrient material* X. An adequate amount of oxygen and absence of amino acids Y. The absence of metabolic waste products and an accumulation of carbon dioxide Z. The absence of oxygen and an adequate amount of nutrient material 14. The portion of the curve that represents events occurring from 19-20 hours W. Shows the rates of bacterial reproduction and mortality are not influenced by either an optimum temperature or the presence of oxygen X. Shows a decline in the reproductive rate that is most likely due to the presence of dead bacteria and oxygen Y. Was probably caused by a lack of motility and excess in carbon dioxide Z. Was probably caused by accumulated metabolic waste products and the lack of oxygen * 15. What will probably occur if the broth is incubated at a temperature of 32°C instead of 37°C? W. The bacterial count will rise sharply during the first hour X. The number of dead bacteria will rise sharply during the first hour Y. The number of bacteria will not reach the 5 million per mL of broth in 15 hours * Z. The period of reproduction will be shorter 16. What will probably occur if the pH of the broth is increased to 7.0 and the incubating temperature is increased to 38°C? W. All the bacteria will die during the 1st hour X. The growth curve will resemble the one displayed in the graph Y. The bacterial count will reach a maximum at about 15 hours Z. Not enough information is available to offer a hypothesis* For questions 17-23 choose the word that best matches each numbered statement. Words can be used once, more than once, or not at all. Photolysis Oxidative phosphorylation Carbon dioxide fixation Transposonase Buffer action 17. Contributes to genetic shuffling in cells of organisms – Transposonase 18. Production of glyceraldehydes 3-phosphate (G3P) using rubisco – carbon dioxide fixation 19. Converts molecules of ADP to ATP molecules – oxidative phosphorylation 20. Homeostatic mechanism that prevents acidosis or alkalosis – buffer action 21. Splits water into hydrogen ions and oxygen ions - photolysis 22. Is included in a noncyclic electron flow in which P680 captures electrons – photolysis 23. Usually involves chemiosmosis in membranes - oxidative phosphorylation 24. Carbon 14 would be used in a study of photosynthesis to demonstrate W. the path of carbon in the Calvin cycle* X. That oxygen gas is produced from carbon dioxide during photolysis Y. That plants release carbon dioxide during the day and night Z. The role of carbonic acid in the carbon dioxide fixation phase 25. The nerve cells of earthworms and humans W. are organized into a central nervous system and a peripheral nervous system X. Respond to stimuli slower than endocrine responses Y. Transmit electrochemical impulses* Z. Use neurotransmitters 26. Meiosis is a process that W. Produces genetically similar gametes X. Prevents chromosomal mutations Y. Produces haploid sperm cells* Z. Does not include cytokinesis 27. The main wastes excreted by protozoans and hydra include water, CO 2, mineral salts, and W. Urea X. Ammonia* Y. Uric acid Z. Creatinine 28. Which does not describe poriferans (sponges)? W. Choanocytes line the interior of the body X. Most are hermaphroditic Y. Many species possess spicules Z. Cnidocytes are used to capture food * 29. The part of the human gut mainly involved with the absorption of water is the W. Duodenum X. Jejunum Y. Ileum Z. Colon* 30. The return of lamprey to their home river or stream from the sea is the result of W. Simple reflex action X. Habituation Y. Operant conditioning Z. Imprinting* 31. An underdeveloped neurohypophysis (Posterior pituitary gland) may result in W. Inadequate regulation of the osmolarity of blood* X. A deficiency of growth hormone (GH) Y. A deficiency of thyroid stimulating hormone (TSH) Z. Improper functioning of the immune system 32. The evolution of angiosperms as land plants is mainly the result of W. The use of flagellated gametes X. The development of colorful flowers Y. An independent gametophyte Z. Double fertilization * 33. Which of the following is formed when DNA combines with histones? W. Mesosomes X. Nucleosomes* Y. Ribonucleoproteins Z. Plasmid 34. Which statement correctly describes enzymes? W. The optimum temperature for enzyme action in most plants is about 25°C* X. The optimum temperature for enzyme action in humans is about 40°C Y. Most enzyme function optimally at a pH between 3.0 and 9.0 Z. Enzymes elevate the activation energy of a reaction 35. A lack of dictyosomes in the Golgi apparatus can adversely affect W. Transcription of amino acids into polypeptides X. The cytoskeleton of the cell Y. Refinement of the ribosomal products* Z. Oxidative phosphorylation 36. Certain organ systems carry out filtration, secretion, and reabsorption in order to W. Regulate osmolarity* X. Detoxify the blood Y. Regulate blood volume Z. Actively transport chylomicrons across a membrane 37. Scientists think that a certain protest, called a chytrid, may be a common ancestor of fungi and animals because it W. Reproduces like a zygomycete and has DNA X. Is heterotrophic and has glycogen Y. Is autotrophic and has a cell wall made of chitin Z. Has a cell wall made of chitin and contains certain proteins found only in animal cells * 38. A cellular process that generates maximum energy from a single glucose molecule is W. Miochondiral chemiosmosis* X. Lactic acid fermentation Y. Glycolysis Z. Reduction of pyruvate 39. One colony of E. coli displayed a shape that was different from all neighboring colonies. The most probable reason for the different shape is the presence of a(n) W. Viroid X. Prion Y. Episome* Z. F-plasmid 40. During differentiation, the archenteron of a frog embryo develops into the W. Coelom X. Neural tube Y. Gut* Z. Skeletal system 41. Which of the following is not a factor in the establishment of community equilibrium? W. r-selected species replacing K-selected species* X. Localized extinctions Y. Increasing predation and competition Z. Increasing stability and diversity 42. A corn seed will not germinate normally if its W. Coleoptile outgrows the plumule (young leaf) X. Cotyledon does not absorb nutrients from the endosperm* Y. Colerhiza envelops the radical (young root) Z. Hypocotyl reacts positively to geotropism 43. In humans and birds, the organ mainly responsible for deamination of excess proteins is the W. Spleen X. Kidney Y. Caecom Z. Liver* 44. In the human respiratory system, pseudostratified ciliated columnar epithelium can be found lining the W. Mouth X. Pharynx Y. Trachea* Z. Alveoli 45. Among prokaryotes, a method of genetic recombination involving the inclusion of genes from the environment is called W. Transformation* X. Transduction Y. Conjugation Z. DNA methylation 46. Test tube A contains 5 mL of a mixture of glucose and Benedict’s solution. Test tube B contains 5 mL of a mixture of starch and Benedict’s solution. Test tube C contains 5 mL of Benedict’s solution. The three test tubes are immersed in a hot water bath for 5 minutes. Which is the most probable outcome? W. The contents of tube A turn brick red in color and the contents of tube B turn green* X. The contents of tube A turn brick red in color and the contents of tube B remain blue Y. The contents of tube A turn brick red in color and the contents of tube C turn green Z. The contents of test tube C turn colorless 47. Which of the following statements is correct? W. The expression ΔG = ΔH-TΔS shows that free energy (G) is directly related to entropy (S) X. A spontaneous change in a system involves an increase in free energy Y. The product of an exergonic reaction contains more energy than the reactants Z. Energy coupling in metabolism uses exergonic reactions to drive endergonic reactions* 48. A plant cell immersed in a hypotonic salt solution will W. Remain unchanged because of its cell wall of cellulose X. Undergo plasmolysis Y. Uses its Na+/K+ pump to transport sodium ions out of the cell Z. Gain turgor* 49. What is the significance of gill slits in avian and mammalian embryos? W. They are vestigial structures X. They are analogous structures Y. They are homologous structures* Z. They illustrate Virchow’s declarations: Ontogeny recapitulates phylogeny 50. Partially digested food in the human stomach has a pH of 2. As a result W. Proteins are hydrolyzed to amino acids X. The pylorus secretes the enzyme enterokinase Y. Bicarbonate ions in pancreatic juice are neutralized in the duodenum Z. Many bacteria are killed* 51. The evolutionary divergence of Darwin’s finches was mainly the result of W. Bottleneck effect X. Microevolution* Y. Mutations Z. Natural selection 52. Following mitosis, a plant cell will not develop a cell plate between daughter cells unless on of the following is present W. Gibberlins X. Cytokinins* Y. Abscissic acid Z. Cyclic AMP (cAMP) 53. Which organism uses flame cells to carry out osmoregulation? W. Fluke X. Planaria* Y. Roundworm Z. Earthworm 54. The production of RNA from DNA is called W. Transduction X. Translation Y. Replication Z. Transcription* 55. Speciation among animals is least affected by W. Geographic isolation X. Sexual reproduction Y. Selection Z. Asexual reproduction* 56. Isomerases are enzymes found in plant cells that convert one sugar into another sugar. Which of the following sugars is not converted as a result of an isomerase? W. Glucose X. Galactose* Y. Fructose Z. Dextrose 57. Racemization is a process of fossil dating by means of W. Determining the ratio of L-amino acids and D-amino acids* X. Discovering evidence in sedimentary rock layers Y. Coprolite examination Z. Radiometric dating 58. An aneuploid individual whose cells contain two Barr bodies is a W. Female with 44 XXX chromosomes* X. Female with 44 XX chromosomes Y. Male with 44 XXY chromosomes Z. Male with 44 XYY chromosomes 59. Two scientists who postulated that evolutionary adaptations were the result of interactions between organisms and their environments are W. Darwin and Lamarck* X. Lyell and Malthus Y. Cuvier and Wallace Z. Linnaeus and Aristotle 60. Which of the following correctly describes an enzyme-controlled reaction? W. A lower activation energy enables a fast reaction* X. The reaction proceeds rapidly, then stops above its optimum pH Y. The rate of reaction is lowered be decreasing the number of enzyme molecules Z. Active sites are located on substrate molecules 61. The crossbreeding of two different inbred varieties may produce individuals that exhibit W. Darwinian fitness X. Hardy-Weinberg equilibrium Y. Balanced polymorphism Z. Hybrid vigor* 62. Positive feedback W. Prevents small changes in the internal environment from becoming too large X. Triggers enhancement, or amplifies, a change in the internal environment* Y. Counteracts all changes in the internal environment Z. Functions only in vertebrates 63. In mammals, mitosis is not involved with W. Differentiation X. Maintaining numbers of erythrocytes* Y. Maintaining numbers of leukocytes Z. Tissue growth and repair 64. One strand of a double helix has a base sequence of CATTGG. The complementary strand has a sequence of W. GTUUCC X. GUAACC Y. CUAACC Z. GTAACC* Use the diagram below to answer questions 65-71. 65. The name of the process depicted is W. Transcription X. Translation* Y. Replication Z. Transduction 66. The label D is showing W. Exon X. Intron Y. Anticodon Z. Codon* 67. The label A is showing W. Amino acid* X. Anticodon Y. Codon Z. Aminotransferase 68. The label G is showing W. Amino acid X. Peptide chain* Y. Peptidyl transferase Z. Peptide bond 69. The label C is showing W. Amino acid X. Codon Y. Anticodon* Z. tRNA 70. The label B is showing W. Amino acid X. Codon Y. Anticodon Z. tRNA* 71. The label E is showing W. DNA X. tRNA Y. rRNA Z. mRNA* 72. Which of the following is not a hormone W. Cholecystokinin X. Epinephrine Y. Gastrin Z. Thrombin* 73. Which of the following is not a function of gastric juice? W. Hydrolysis of starch X. Converting pepsinogen to pepsin Y. Production of chyle* Z. Destroying bacteria 74. Haversian systems are necessary for the normal functioning of W. Excretion in cyclostomes X. Osseous tissue in humans* Y. Air cavities in birds Z. Olefactory reception in elasmobranchs 75. An organism that is not radially symmetrical is the W. Starfish X. Hydra Y. Sea urchin Z. Roundworm* 76. The picture represents a process that helps read a genetic code. The apparatus is a W. Gel electrophorsis X. Photospectrometer Y. Micropipette Z. Thermocycler for Polymerase chain reaction (PCR) 77. The mesophyll of plant cells possess Photosystem I & II located in W. Thylakoids* X. Chlorophyll a Y. Carotenoids Z. Plastoquinones 78. Which is correct about the endoplasmic reticulum (E.R.) of a cell? W. It is present in both eukaryotic and prokaryotic cells X. Its composition differs from the plasma membrane Y. The amount of rough E.R. corresponds to the degree of carbohydrate synthesis Z. The smooth E.R. is mainly involved with lipid synthesis* 79. A major characteristic of non-Mendelian inheritance is that W. Cytoplasmic genes are nonfunctional X. Not all genes of a eukaryotic cell are located in nuclear chromosomes* Y. Maternal inheritance does not include mitochondrial genes in mammals Z. Chloroplasts lack genes 80. In Drosophila, the allele for vestigial wings (w) is recessive to the normal long wing allele (W). The allele for white eye (r) is recessive to the allele for normal red eye (R) . In mating WWRR X Wwrr (assuming large numbers of offspring), what proportion of offspring will show normal traits (Long wings and red eyes)? W. 100%* X. 75% Y. 50% Z. 25% 81. An adaptation present in osteichthyes and not in chondrichthyes is/are W. A swim bladder* X. Scales Y. Gills Z. Lateral line system 82. Which of the following would not be essential in osmoregulation performed by the kidneys? W. Adrenocorticotropic hormone* X. Antidiuretic hormone Y. Juxtaglomerular apparatus Z. Aldosterone 83. B and T cells of the immune system are alike because both W. Produce cytokines X. Are polymorphs Y. Possess antigen receptors* Z. Produce antibodies 84. Pluripotent stem cells develop into W. Erythorcytes, leukocytes, thrombocytes* X. Cuboidal, columnar, squamous cells Y. Gamma globulins, antibodies, fibrinogen Z. Ectoderm, mesoderm, endoderm 85. The heme group of a cytochrome molecule enables W. Phycobilins in plants to promote pollination X. P680 pigments of a Photosystem II group to absorb light Y. Mitochondrial DNA to undergo replication Z. Redox reactions to take place in an electron transport system* 86. The chromosomal abnormality called trisomy, which causes Down syndrome in humans is caused by the W. Nondisjunction of chromosome 21* X. Translocation of chromosome 21 Y. Inversion of chromosome 21 & 23 Z. Nondisjunction of chromosome 13 87. CAM plants are similar to C4 plants because both W. Undergo photorespiration X. Incorporate CO2 into 4 carbon organic acids* Y. Convert CO2 into phosphoglyceraldehyde (G3P) Z. Have large amounts of lignin in their stems 88. Replication of new DNA strands requires the presence of W. mRNA* X. Primer RNA Y. tRNA Z. Ligase 89. Oogenesis does not produce a monoploid ovum until W. The first meiotic division X. A secondary oocyte is formed Y. Fertilization by a sperm cell triggers a second meiotic division* Z. The first polar body is formed 90. Ecologists assess the responses of an organism to its environment by (a) the amount of energy the organism uses to adapt to environmental conditions, and (b) the amount of energy remaining to carry out essential life functions. The concept of assessing the responses of an organism in relation to energy use is called W. The principle of allocation* X. Regulation Y. Conformation Z. Semelparity 91. Osmoregulators in the hypothalamus control secretion of W. Thyroid stimulating hormone (TSH) X. Antidiuretic hormone (ADH)* Y. Aldosterone Z. Prostaglandins 92. Which type of survival mechanism is used by a bird that lays brown eggs in nests located in trees? W. Batesian mimicry X. Aposematic coloration Y. Mullerian mimicry Z. Cryptic coloration* 1 2 A 3 B 4 C 93. The illustration shows that W. The epitopes on antigen 1 cannot bind to any antibody X. The epitopes on antigen 2 can bind to antibody A Y. The epitopes on antigen 4 can only bind to antibody C Z. The epitopes on antigen 1 can bind to antibody A* 94. An endocrine gland that responds to stimuli by nerve cells is the W. Parathyroid X. Adrenal cortex Y. Adrenal medulla* Z. Pineal 95. Albumin is characterized by tightly folded groups of molecules. The structural form of albumin is the result of W. Dehydration synthesis X. Peptide bonds Y. Disulfide linkages between cysteine amino acids* Z. Hydrophilic amino acids 96. A pyramid of biomass shows that W. Energy content decreases from base to apex* X. Energy content increases from base to apex Y. Primary consumers are least numerous Z. Tertiary consumers are most numerous 97. A rearrangement of one nucleotide in a single gene may result in a(n) W. Point mutation* X. Deletion Y. Insertion Z. Translocation 98. The substance that makes up about 80% of a cells cytosol is W. Water* X. Tubulin Y. Glucose Z. Bicarbonate ions 99. Which statement is correct? W. The human alimentary canal is an ecosystem* X. The present increase in human population is due to an increased birth rate Y. A grassland or desert biome is classified by its dominant animals Z. Estuaries lack phytoplankton and larvae of organisms 100. The target organs of many hormones will respond only when W. Calcium ions are present X. Adenylyl cyclase is degraded Y. Cyclic AMP (cAMP) is present* Z. Phosphorylase is present 101. HIV reduces the efficiency of the immune system by attacking W. B cells X. Suppressor T cells Y. Helper T cells* Z. Plasma cells 102. Aquatic autotrophs cycle carbon by means of a chemical reaction involving W. Water and limestone X. Carbon dioxide and limestone Y. Carbon dioxide, water, and limestone* Z. Respiratory carbon dioxide and water 103. Dolly, the cloned sheep developed by Dr Ian Wilmut is W. Genetically identical to the sheep that supplied DNA from an udder cell* X. Genetically identical to the sheep that supplied the enucleated egg cell Y. Genetically identical to the sheep that was the surrogate mother Z. A monoploid individual 104. In mitosis, the events G1 S G2 M are followed by W. Reconstitution of nucleoli X. Kinetochore formation Y. Migration of centrioles Z. Cytokinesis* 105. Field mice will emigrate from a niche formerly shared with owls to another area to avoid excessive predation and consequent loss of numbers. The new environment occupied by the field mice is a(n) W. Successive habitat X. Realized niche Y. Cline Z. Isolated territory* 106. A student prepared a temporary wet mount of stained onion skin cells and then viewed them under low power and high power objectives of a compound light microscope. Which organelle could not be viewed by the student? W. Cell wall X. Cytoplasmic strands Y. Chloroplast* Z. Nucleus 107. When population growth is not restrained by limiting factors, numbers of individual organisms are likely to W. Increase exponentially* X. Increase sinusoidally Y. Stabilize as births = deaths Z. Decrease as a result of competition for mates 108. A metabolic pathway common to both fermentation and cellular respiration is W. The oxidation of pyruvate to lactate by NADH X. Glycolysis* Y. An electron transport chain Z. Krebs cycle 109. The hormone calcitonin mainly functions to W. Inhibit Ca++ ion excretion by the kidneys X. Promote absorption of Ca++ ions in the kidneys Y. Raise the blood calcium level Z. Lower the blood calcium* 110. Homeotic genes influence W. Non-Mendelian inheritance X. Development of body parts in sequence* Y. Blending inheritance Z. Synthesis of melanin 111. Chemiosmosis involves all of the following except W. A membrane potential X. Selective permeability Y. Passive transport Z. Potassium ion transport* 112. Newly formed colonies of bacteria in a culture medium quickly dwindle in size and disappeared despite the fact that all essential living conditions were optimum. The most probable cause for the decline in bacterial colony population was the occurrence of W. A mutation X. A bacteriophage infection* Y. Transformation Z. Sexual reproduction and recombination 113. In a plant cell, chloroplasts are to mitochondria as W. Photosynthesis is to glycolysis X. Grana are to outer membrances Y. Photolysis is to the Krebs cycle Z. Thylakoid membranes are to cristae* 114. Astral rays that appear during mitosis are composed of W. Actin polymers X. Myosin polymers Y. Microtubules* Z. Histones 115. A laboratory technique in which DNA is inserted into eukaryotic cells is W. Electroporation* X. Electrophoresis Y. Northern blotting Z. Southern blotting 116. Living systems are regulated by the second law of thermodynamics, which refers to W. Potential energy X. Entropy* Y. Conservation of matter Z. Conservation of energy 117. When large numbers of roan cattle are interbred, the percentages of offspring are 25% red, 50% roan, and 25% white. The results provide evidence for W. Natural selection X. Incomplete dominance* Y. Cytoplasmic inheritance Z. Aneuploidy 118. Which statement correctly describes fermentation? W. Involves the aerobic catabolism of organic nutrients X. Involves the anaerobic anabolism of organic nutrients Y. Always releases carbon dioxide Z. Sometimes carried out by muscle cells* 119. The graph below represents the relationship between population growth and time. Limiting factors, such as overcrowding and availability of essential resources and mates, are considered in the graph. The “K” in the graph represents W. Exponential growth X. Logistic population growth Y. Biotic potential Z. Carrying capacity* K 120. A class of mollusks whose members use a radula to feed by scraping algae off rocks is W. Gastropods* X. Bivalves Y. Cephalopods Z. Decapods 121. Based on comparison of differences and similarities in their amino acids, which pair of chordates are most closely related? W. Lamprey and snakes X. Ducks and crocodiles* Y. Sea bass amd sea squirts Z. Sharks and sparrows 122. A nerve impulse crosses from the presynaptic membrane of one neuron to the plasma membrane of the cyton or dendrites of another neuron by means of W. An influx of Ca++ ions X. A neurotransmitter* Y. Cyclic AMP (cAMP) Z. An endorphin 123. Synapsis of homologous chromosomes in prophase I of meiosis involves W. Attraction and synthesis X. Division and separation Y. Attraction and pairing* Z. Duplication and separation 124. Inhalation and exhalation in humans are regulated by the medulla oblongata, diaphragm, and W. Splenic nerves X. Vagus nerves Y. Sciatic nerves Z. Phrenic nerves* 125. Sex pili are reproductive adaptations characteristic of some W. Sponges X. Protozoans Y. Bacteria* Z. Sharks 126. Recombinant DNA is produced in the laboratory using W. Ligase and transcriptase X. Ligase and endonuclease* Y. Polymerase and topoisomerase Z. Endonuclease and DNA polymerase 127. Which of the following hydrolyzes polypeptides? W. Enterokinase X. Amylopsin Y. Trypsin* Z. Cholecystokinin 128. During aerobic respiration, the matrix of a mitochondrion is involved in the following biochemical pathway W. Krebs cycle NADH2 Electron transport chain oxygen* X. Glycolysis Krebs cycle FADH2 ATP Y. Pyruvate Krebs cycle ATP oxygen Z. Krebs cycle FADH2 oxidative phosphorylation ATP 129. Which of the following correctly describes muscle action? W. Muscle contraction involves the release of Ca++ ions from the sarcoplasmic reticulum* X. Muscle contraction involves active transport of Ca++ ions into the sarcoplasmic reticulum Y. Cholinesterase is an enzyme that neutralizes acetylcholine only in smooth muscle Z. ATP is used to release acetylcholine from synaptic vesicles 130. Which is a false statement about the differences between monocot and dicot stems? W. One cotyledon is found in monocot seeds & two cotyledons are found in dicot seeds X. Petals occur in multiples of three in monocots and multiples of four or five in dicots Y. Vascular bundles are scattered in monocot stems and occupy a central stele in dicot stems* Z. Main veins are parallel in monocot leaves and branched or netted in dicot leaves 131. A subatomic particle that has a mass of one Dalton (amu) and helps set up an electrochemical gradient in cell membranes is a(n) W. Electron X. Neutron Y. Proton* Z. Neutrino 132. A deficiency of isomerase in a pregnant mammal will affect normal milk production from mammary glands because W. Glucose cannot be converted to galactose* X. Galactose cannot be converted to lactose Y. Galactose is not an isomer of glucose Z. An isomerase cannot act on simple sugars 133. Cellular respiration involves a negative ΔG equal to -686 kcal, which indicate the reactions are W. Endergonic X. Exergonic* Y. Enzyme controlled Z. Unaffected by Le Chatelier’s principle 134. Which statement correctly describes the change in free energy (ΔG) of a chemical system? W. Directly proportional to the total energy (enthalpy)* X. Unaffected by the system’s entropy Y. A positive ΔG indicates a spontaneous reaction Z. Does not consider the absolute temperature in Kelvin units 135. A functional group that stabilizes the structure of proteins is the W. Carbonyl group >C=O X. Carboxyl group –COOH Y. Amino group –NH2 Z. Sulfhydryl group –SH* 136. The chemical link between glycolysis and the Krebs cycle is W. Reductive phosphorylation X. Chemiosmosis Y. Conversion of oxaloacetate to actyl CoA Z. Conversion of pyruvate to actyl CoA* 137. Absorption and action spectrums of chlorophyll a show that W. The color of chlorophyll a results from the absorption of green wavelengths of light X. Chlorophyll a has only one absorption peak Y. Carotenoids and phycobilins are not involved in photosynthesis Z. The red and blue regions of the spectrum are most effective in photosynthesis* 138. If a DNA code reads CAG, the codon for valine synthesis is W. GUC* X. AUC Y. UTC Z. GTC 139. A nucleus, chloroplast, and a mitochondrion are similar because each W. Is derived from the endoplasmic reticulum X. Is not enveloped by similar membranes Y. Contains DNA* Z. Is a structure that makes up the cytoskeleton 140. Which structure is not derived from the endomembrane system? W. Smooth ER X. Peroxisome* Y. Lysosome Z. Golgi apparatus 141. Muscle cells contract when actin filaments work in conjunction with contractile structures called W. Microtubules X. Fibronectins Y. Myosin filaments* Z. Z-lines 142. A main function of the extracellular matrix (ECM) of an animal cell is W. Support and anchorage* X. To produce collagen Y. To synthesize proteoglycans Z. To actively transport macromolecules 143. A disease that destroys the cytoskeleton will probably interfere with W. DNA transcription X. Cell division* Y. Phagocytosis Z. Active transport 144. Which pair of organelles are found in plant and animal cells? W. Mitochondrion and vacuole* X. Centriole and lysosome Y. Centrosome and thylakoid Z. Tonoplast and Golgi apparatus 145. Which of the following cells would a researcher use to clearly observe lysosome function? W. Neuron X. Phagocyte* Y. B lymphocyte Z. Pancreatic cell 146. Glycoproteins and glycolipids are involved in W. Cotransport X. Osmosis Y. Cell to cell recognition* Z. Facilitated diffusion 147. Which statement correctly describes osmosis, or the movement of water through a selectively permeable membrane? W. A gradient is not necessary X. The free energy of the system increases Y. The hydrogen bonds facilitate passage of water molecules across the membrane Z. The entropy increases in the system* 148. Ions diffuse across a membrane in response to the W. Electrochemical gradient* X. Concentration gradient Y. Electrical gradient Z. Relative masses 149. Layers of membranous sacs with cisternae and with cis face and trans face polarity accurately describes W. Golgi apparatus* X. Rough ER Y. Smooth ER Z. Nucleolus 150. As a result of autophagy W. The heme group of a hemoglobin molecule is removed X. Calcium ions are stored in muscle cells Y. Residual bodies are formed from vesicles Z. Worn out organelles are destroyed* 151. A cellular adaptation of animals that permits the transfer of ions between adjacent cells is called a W. Gap junction* X. Plasmodesmata Y. Tight junctions Z. Desmosomes 152. Which statement does not accurately describe mitochondria? W. They have inner folded membranes called cristae, which are involved in aerobic cellular respiration X. They have a matrix containing enzymes, which are involved in the Krebs cycle Y. They are found only in eukaryotic cells Z. They contain heredity material but do not replicate the heredity material or themselves* 153. A normal cell has an electrical charge difference across its plasma membrane and the cause is more anions inside the cell than outside. The anions mainly responsible for the negative voltage are W. Chloride and calcium ions X. Sulfate, phosphate, and amino acid ions* Y. Bicarbonate ions and fatty acids Z. Nitrate and bromide ions 154. Cilia and flagella feature a 9+2 pattern of microtubules. The movement of cilia and flagella are the result of W. Cytoplasmic streaming inside the cell X. Movement of the cytoskeleton’s intermediate filaments Y. Protein dyneins, which are powered by ATP molecules* Z. Rotational movement of basal bodies 155. Certain weaknesses in the five kingdom classification system caused taxonomists to develop a three domain system of classification. A main reason for creating the three domain system is to W. Give more evolutionary significance to the divisions called Eubacteria and Archaebacteria* X. Give more evolutionary significance to Eubacteria as prokaryotes Y. Decrease the evolutionary significance of Protista Z. Separate heterotrophs from autotrophs 156. Cells lining the small intestine transfer glucose molecules into cells from the lumen by W. Simple diffusion X. Facilitated diffusion Y. Proton pumps Z. Active transport* 157. In human females, inactivation of an X chromosome during meiosis is caused by W. Addition of methyl groups to either nucleotides or to nitrogenous bases* X. Removal of sulfhydryl groups from telomeres on an X chromosome Y. Meiotic nondisjunction Z. Translocation and deletion 158. Along which of the following DNA sequences will a specific enzyme recognize a cutting site? W. AGTC;TCAG X. GGCC;CCGG* (Palindromic) Y. ACCA;TGGT Z. TTTC;AAAG 159. Bacterial DNA is protected from its viral-degrading enzymes by other enzymes called W. Polymerases X. Endonucleases Y. Methylases* Z. Proteases 160. Which of the following is used to make a chimeric genome? W. Restriction nucleases* X. Transposase Y. Glyphosate Z. DNA polymerase 161. Restriction enzymes, commonly called “scissors”, work cooperatively with another enzyme called W. Methylase X. Deaminase Y. Synthetase Z. Ligase* 162. Which sex genotype is not a result of nondisjunction? W. XXY X. XO Y. XYY Z. XX* 163. The detection and analysis of nucleotide sequences in homologous strands of DNA uses all of the following techniques except W. Restriction enzymes X. Electroporation* (electric current opens pores in membrane) Y. Electrophoresis Z. Southern blotting 164. In humans, an AB blood type is the result of W. Codominance* X. Incomplete dominance Y. Polygenic inheritance Z. Epistasis 165. Both a male and female mouse are carriers of a deadly recessive gene. What percentage of their offspring would probably survive? W. 0% X. 25% Y. 50% Z. 75%* 166. Two long winged fruit flies were mated and produced offspring that included 48 long winged flies and 14 short winged flies. The experimental procedure was performed to W. Determine if long wings is sex-linked X. Determine if short wings is dominant or recessive* Y. Provide experimental support for Mendel’s law of dominance Z. Initiate a population study 167. The appearance of mammals about 250 million years ago is an example of W. Catastrophism X. Microevolution Y. Macroevolution* Z. Divergent evolution 168. Balanced polymlorphism is the ability of natural selection to maintain diversity in a population by means of W. Stabilizing varitations X. Adaptive radiation Y. Inbreeding homozygotes Z. Crossbreeding of heterozygotes* 169. Which is correct about the three domain system of classification? W. Protista are excluded from the domain Eukarya X. Eukaryotes and prokaryotes are grouped together Y. The domain Eukarya includes all organisms except Eubacteria and Archaebacteria* Z. It includes a subdomain for protists 170. Evolution tends to occur if the frequency of genes in a population changes. Which factor is least likely to affect gene frequency in a population? W. Mutation rate X. Geographic isolation Y. Genetic drift Z. Inbreeding* 171. The evolutionary relationships of organisms can best be inferred from differences and similarities in W. Analogous structures X. Amino acid sequences in common proteins* Y. Index fossils Z. Vestigial organs 172. Giant forms of jimsonweed plants are occasionally observed growing alongside normal sized plants. Geneticists explain the appearance of the giant plants as a result of W. Punctuated equilibrium X. Gradualism Y. Sympatric speciation* Z. Allopatric speciation 173. In humans brown eyes are dominant over blue eyes. About 16% of the population has blue eyes. What percentage of the population is heterozygous for brown eye color? W. 24% X. 40% Y. 48%* Z. 60% 174. A process that tends to add new alleles to a gene pool is W. Mutation* X. Genetic drift Y. Meiosis Z. Segregation 175. An example of coevolution is/are W. Flower pollination and food collection by bees* X. The scutes of a snake and splint bones of a horse Y. Gills slits in sharks and those in turtle embryos Z. Similarities in the chemical composition of enzymes in pigs and cattle 176. The hominid fossil, Australopithecus afarensis, called Lucy, has a significant place in the scheme of evolution because she is the first known human-like animal W. Who fashioned tools X. Who had reduced canine teeth and brow ridges Y. To possess a coccyx Z. To walk erect on two legs and have rounded jaws* 177. In the algebraic expression p2 + 2pq + q2 = 1 the q2 refers to W. The frequency of homozygous dominant individuals X. The frequency of the homozygous recessive individuals* Y. The frequency of the heterozygous individuals Z. The gene frequency in a given population 178. A trochophore larva W. Indicates a relationship between mollusks and annelid worms* X. Is the parasitic larva of a liver fluke Y. Resembles an ancestral form of echinoderms Z. Is an intermediate form between segmented worms and insects 179. Which statement is correct? W. Genetic drift is not as important in human evolution today as it was 30, 000 years ago* X. Bipedalism had no effect on ancestral human’s use of hands Y. Femurs are the most commonly found osseous fossils Z. Flame cells are found in the excretory system of protochordates 180. Which series of animal evolution is correct? W. Agnathans Placoderms Osteichthyes* X. Amphibians Reptiles Therapsids Y. Monotremes Placental mammals Marsupials Z. Homo erectus Homo habilis Homo sapiens 181. In ducks and chickens, fertilized eggs of intermediate weight usually hatch with greater frequency than those of other weights. This illustrates a type of selection called W. Disruptive X. Stabilizing* Y. Directional Z. Natural 182. Allele E, found in a large randomly mating population, occurs at a frequency of 68 per 100 individuals. Approximately what proportion of individuals will be heterozygous for the allele? W. 27% X. 32% Y. 45%* Z. 55% 183. The type of selection that helped the horse evolve from Eohippus to Equus is W. Stabilizing X. Disruptive Y. Natural Z. Directional* 184. Which of the following pairs is incorrect? W. Monocot - parallel venation X. Conifer – heterosporous Y. Fern – male & female gametophytes* Z. Bryophyte – flagellated male gametophytes 185. The stele of a root is adapted for the transport of substances by possessing W. Xylem and phloem* X. Meristems and sclerenchyma Y. Parenchyma and cortex Z. Root hairs and Casparian strip 186. A germinating pollen grain, including its pollen tube is a(n) W. Microspore X. Modified antheridia Y. Immature sporophyte Z. Male gametophyte* 187. A megapascal (MPa) is a unit of W. Osmotic pressure in root hairs X. Water pressure in plant cells* Y. Pressure within air spaces in a leaf Z. Transpiration from leaves 188. In winter, some deciduous trees carry out gas exchange by using specialized structures called W. Abscissal scars X. Ligules Y. Lenticels* Z. Trichomes 189. Indian pipe is a colorless angiosperm that is adapted to survive as a(n) W. Epiphyte X. Saprobe* Y. Parasite Z. CAM plant 190. When touched, the leaflets of the mimosa plant fold and petioles droop as the result of W. Turgor pressure loss* X. Proton pumps driving K+ ions into cells Y. The release of ethylene gas Z. An electrochemical gradient that drives Na+ ions out of cells 191. Photoperiodism, the physiological response of a plant to changes in the length of day and night, depends mainly on the action of W. Gibberellins X. Auxins Y. Abscissic acid Z. Phytochromes* 192. Since a burning plant usually emits fumes that include ammonia, it is reasonable to conclude that plant tissue contains W. Starches X. Lignin Y. Fructose Z. Proteins* 193. Observing a mature corn stem with a hand lens will reveal the presence of W. A pericycle X. Collenchyma tissue Y. Scattered vascular bundles* Z. A stele 194. A deficiency of potassium salts in soil will probably W. Weaken root pressure X. Inhibit root hair development Y. Cause chlorosis Z. Interfere with guard cell action* 195. Phloem sap flows from a sugar source to a sink as the result of W. Hydrostatic pressure* X. Active transport Y. Cytoplasmic streaming Z. Transport by companion cells 196. Nitrate ions (NO3-), sulfate ions (SO42-) and phosphate ions (PO43-) pass into root cells by W. Simple diffusion X. Endocytosis Y. Cotransport* Z. Guttation 197. Which pair of terms in incorrect? W. Companion cell – phloem X. Tonoplast – membrane covering central vaculole Y. Lignin – cell wall component Z. Apical meristem – region of cell division in leaves* 198. The gallbladder is the target organ of the intestinal hormone W. A cholecystokinin* X. Enterogastrone Y. Insulin Z. Gastrin 199. Which vessel contains blood heavily laden with glucose following a meal? W. Thoracic duct X. Hepatic vein Y. Hepatic portal vein* Z. Femoral vein 200. A function of microvilli is to W. Protect villi X. Increase surface area of villi* Y. Destroy pathogenic organisms Z. Absorb complex fatty acids from intestinal chyle 201. Helicobacter pylori bacteria have been found to be a major cause of stomach ulcers. They survive in a highly acidic environment because W. They have resistant cell walls X. They are covered with jelly-like capsules Y. They secrete the enzyme urease which converts urea to ammonia* (Ammonium hydroxide) Z. Their optimum pH for metabolism is 2.0 202. Each 100 mL of deoxygenated blood normally contains about 5 mL of carbon dioxide. About what percent of carbon dioxide is transported in blood plasma as bicarbonate ions? W. 75%* X. 50% Y. 25% Z. 10% 203. Which statement is incorrect about carbon dioxide gas generated during cellular respiration? W. A small percentage dissolves in blood plasma X. It combines with the globin group of hemoglobin Y. It combines with the heme group of hemoglobin* Z. It is carried in blood plasma as bicarbonate ions 204. The Bohr shift is a process that W. Regulates the change from deoxygenated blood to oxygenated blood in the alveoli of lungs X. Regulates affinity of hemoglobin for oxygen molecules* Y. Describes the change of an iron ion to its reduced state Z. Controls the breathing center in the medulla oblongata 205. Which gas has the greatest chemical attraction for hemoglobin? W. Carbon monoxide* X. Carbon dioxide Y. Oxygen Z. Nitrous oxide 206. An organ whose efficiency will be affected by a deficiency of Purkinje fibers is the W. Atrial-ventricular node of the pacemaker X. Smooth muscle of the stomach Y. Pituitary gland Z. Ventricular myocardium* 207. A hormone that stimulates active spermatogenesis in seminiferous tubules is W. FSH* X. LH Y. Estradiol Z. Progesterone 208. Biogenic amines, such as epinephrine and serotonin function as W. Vasoconstrictors X. Vasodilators Y. Neurotransmitters* Z. Inhibitors of action potentials 209. Most endocrinologists think that the “master gland” is not the pituitary gland, but an area in the brain called the W. Pons X. Thalamus Y. Corpus callosum Z. Hypothalamus* 210. Virus infected tissues help neighboring cells ward off virus attacks by producing W. Histamines X. Interferon* Y. Immunoglobulins IgA and IgM Z. Complement proteins 211. A dysfunctional thymus gland is unable to W. Produce major histocompatibility complex (MCH) proteins X. Provide a maturation place for T cells* Y. Produce plasma cells Z. Destroy worn out red blood cells 212. Cytotoxic T cells or killer cells, produce a protein called perforin which, W. Opens lesions in an infected cell’s membrane, exposing pathogens to immune antibodies* X. Regulate genes that initiate interleukin production Y. Activates major histocompatibility complex markers Z. Stimulates histamine formation from tissues 213. HIV (human immunodeficiency virus) causes aids (acquired immunodeficiency syndrome) as the result of W. Infecting and destroying T cell helpers bearing CD4 molecules* X. Destroying phagocytes Y. Inhibiting T cell maturation in the thymus gland Z. Counteracting humoral-mediated immunity activities 214. When skeletal muscle contracts W. A bands shorten X. Z lines moves farther apart Y. H zones widen Z. I bands shorten* 215. Scientists claim that stem cells in a human blastocyst and in umbilical cord blood may be cultured and controlled to W. Produce human clones X. Grow tissues and organs for transplantation* Y. Function as egg cells for in vitro fertilization Z. Supply red blood cells to people suffering from anemia 216. Which statement is incorrect about agnostic behavior? W. It is expressed only by the males of a species* X. It is a common type of behavior Y. It is usually used to establish territorial rights Z. It is characterized by conflicts between members of a species 217. The primary function of denitrifying bacteria is converting W. Nitrites to nitrates X. Nitrates to nitrites Y. Nitrates to nitrogen gas* Z. Nitrogen gas to ammonia gas 218. Nitrogen fixing bacteria may be found in W. Soil rich in organic matter X. Nodules of roots of leguminous plants* Y. Plants that grow in permafrost Z. Roots of xerophytes 219. The primary consumers in a food chain that includes snakes, hawks, crickets, and frogs are W. Snakes X. Hawks Y. Frogs Z. Crickets* 220. The algebraic expression dN/dt = r iN expresses W. Biotic potential* X. Population density Y. Carrying capacity Z. Demographic structure 221. The niche of benthic organisms is W. On a coral reef X. In a eutrophic lake Y. On the deep-sea bottom* Z. In an estuary 222. A food web is composed of interconnected W. Food pyramids X. Energy pyramids Y. Pyramids of biomass Z. Food chains* 223. The ecological succession in an Alaskan forest is : Fireweeds alders (shrubs) aspens (hardwood trees) conifers. The different species that are best adapted to life under prevailing conditions with conifers are part of W. An ecosystem X. A food web Y. A climax community* Z. A deciduous forest 224. A K-selected population is characterized by W. Extensive parental care* X. Many offspring in one reproductive period Y. A high death rate Z. A relatively short life span 225. A herbivorous insect, such as a grasshopper, defends itself against predators by W. Aposematic coloration X. Cryptic coloration* Y. Poisonous secretions Z. A stinging apparatus 226. A J-shaped curve of exponential growth is a feature of populations that W. Have reached their biotic potential X. Are not affected by carrying capacity Y. Show a low intrinsic rate of increase Z. Are introduced into a new environment* 227. The life cycle of a semelparous organism, such as an insect, includes W. Batesian mimicry X. A large number of offspring in a season* Y. courtship as a sexual behavior Z. Parthenogenesis 228. The trophic level that contains the least biomass is usually occupied by W. Herbivores X. Decomposers Y. Tertiary consumers* Z. Producers 229. Transport vesicles produced by the endoplasmic reticulum are processed and sent to other regions of a cell by W. Tubulins X. Glycoxyomes Y. Micorfilaments Z. Golgi apparatus* 230. Some whales and penguins feed on crustaceans called krill, which are classified ecologically as W. Producers X. Primary consumers* Y. Secondary consumers Z. Benthic organisms 231. A region of the brain mainly involved with homeostasis is the W. Hypothalamus* X. Pons Y. Basal ganglia Z. Neopallium 232. A basement membrane is an extracellular matrix that is associated with W. Bone tissue X. Nerve tissue Y. Epithelial tissue* Z. Loose areolar tissue 233. In mammals, release of milk from mammary glands is regulated by W. Oxytocin* X. Progesterone Y. Prostaglandins Z. Melatonin 234. Heterospory in certain bryophytes is an evolutionary adaptation that W. Enabled extensive growth of vascular tissue X. Enabled sexual reproduction in the absence of water Y. Produced separate plants bearing antheridia and oogonia* Z. Produced diploid gametophyte generations that are the dominant plant 235. A standard procedure of genetic engineering is the use of endonucleases to W. Splice together loose ends of DNA fragments X. Remove recognized DNA fragments* Y. Inhibit DNA replication Z. Generate spontaneous mutations 236. The symbiotic relationship between nitrogen fixing bacteria and a clover plant illustrates W. Coevolution* X. Commensalism Y. Convergent evolution Z. Trophic structure 237. The main function of decomposers is to W. Convert free nitrogen into ammonia X. Release nitrogen into the atmosphere Y. Degrade organic compounds into inorganic compounds* Z. Release carbon dioxide into the air 238. Which is the most important factor in the loss of Earth’s biodiversity? W. Depletion of the ozone layer X. The greenhouse effect Y. The release of toxic wastes into the environment Z. Habitat destruction* 239. A three chambered heart is characteristic of a W. Fish X. Salamander* Y. Crocodile Z. Bird 240. A type of isolation not involved in speciation is W. Allopatric X. Sympatric Y. Geographic Z. Competitive exclusion* 241. Demography is the study of W. Biotic potentials and population density X. How populations may change in the future* Y. Density dependent factors and biomass Z. Biogeological cycles and climate change 242. In the developing embryo of a coelomate animal, somites normally give rise to W. Muscles* X. Digestive glands Y. Ganglions Z. Lungs 243. In a humoral response to antigens, B cells give rise to W. Plasma cells* X. Killer T cells Y. Helper T cells Z. Monoclonal antibodies 244. A recent study involving tumor research indicated a relationship between angiogenesis, multiplication of tumor cells, and the enzyme ATP synthetase. Which organelle of tumor cells should be the focus of this study? W. Golgi apparatus X. Endoplasmic reticulum Y. Plasma membrane Z. Mitochondrion* 245. In order to select a gene for a desirable phenotype, it is best to use a nucleic acid sequence called a W. Primer X. Reverse transcriptase Y. Probe* Z. Viral vector 246. In cells, histones help package DNA molecules called W. Exons X. Nucleotides Y. Nucleosomes* Z. Nucleosides 247. According to the first law of thermodynamics, the W. Total energy in a closed system varies with the kinetic energy of the environment X. Total energy in a closed system undergoes a quantitative amount of disorder or randomness Y. Total energy in a closed system is constant* Z. Energy in an open system, such as that in an organism, may be transferred between the system and its environment 248. The codon UGU translates into the amino acid cysteine, the DNA code for this codon is W. TCT X. ACA* Y. TGT Z. ACT 249. Prior to their extinction about 220 million years ago, therapsids gave rise to W. Birds X. Dinosaurs Y. Pterodactyls Z. Primitive mammals* 250. The ability of one gene to control the expression of multiple phenotypes is called W. Polygenic inheritance X. Codominance Y. Epistasis Z. Pleiotropy* 251. Which statement is incorrect about species classified in the phylum Annelida? W. Wastes are removed from the blood and coelomic fluid by metanephridia X. The species lack segmentation and a coelom* Y. The species are hermaphroditic Z. The species have a hydrostatic skeleton 252. The age of fishes, which existed about 400 million years ago, is classified as the W. Mesozoic Era X. Cretaceous Period Y. Carboniferous Period Z. Devonian Period* 253. Cellular respiration involves a negative ΔG equal to -686 kilocalories, which indicates that the reactions of cellular respiration are W. Exergonic* X. Endergonic Y. At equilibrium Z. Not influenced by entropy 254. Enantiomer molecules are W. Structural isomers X. Geometric isomers Y. Optical isomers* Z. Characteristic of cyclic hydrocarbons 255. An amniotic egg, first developed by reptiles, is an evolutionary adaptation that helps a developing embryo by W. Providing nourishment X. Recycling metabolic wastes Y. Preventing dehydration* Z. Enabling gas exchange 256. A corpus luteum is composed of cells that secrete the hormone W. Progesterone* X. Testosterone Y. Estrogen Z. Vasopressin 257. An organelle involved mainly with intracellular digestion is a W. Food vacuole X. Pinocytic vesicle Y. Dictyosome Z. Lysosome* 258. About 16% of humans exhibit attached earlobes, which is a recessive trait. What percentage of the human population are heterozygous individuals? W. 16% X. 36% Y. 48%* Z. 64% 259. Bacteria from a single colony were cultured on a normal nutrient agar medium. The bacteria were then transferred to a culture medium containing the antibiotic terramycin. After 24 hours, a tiny colony appeared on the terramycin agar medium. A reasonable inference is that W. Terramycin induced a mutation X. A mutation had previously occurred spontaneously* Y. Terramycin interfered with the absorption of nutrient material from the culture medium Z. Terramycin had lost its potency 260. Gastric juice does all of the following except W. Destroys bacteria X. Dissolve minerals Y. Participate in erythropoeisis Z. Convert peptides to amino acids* 261. Plasma cells and memory cells of the immune system develop from W. T4 cells X. Hemopoietic stem cells in the red bone marrow Y. B cells* Z. Macrophages 262. A blue eyed child was born to parents with brown eyes. It is most likely that W. One parent was homozygous for brown eyes; the other parent was heterozygous for the trait X. Aberrant multiple alleles were responsible Y. Both parents were heterozygous for brown eyes* Z. The dominant allele for eye color had undergone transposition 263. Book lungs are the respiratory organs found in W. Slugs X. Lungfishes Y. Crickets Z. Spiders* 264. After several hours of exposure to light, the lower epidermis of a leaf from a C 3 plant and a CAM plant were observed under a microscope. A correct observation concerning stomates is W. CAM leaves lack stomates X. Stomates of the C3 plant are slightly open Y. Stomates of the C3 plants are wide open* Z. Stomates of the CAM plant lack guard cells 265. A gas normally used by a facultative aerobic organisms for respiration is W. Carbon dioxide X. Methane Y. Ammonia Z. Oxygen* 266. A carrier, or heterozygous individual, of sickle cell anemia is usually immune to W. Malaria* X. Dengue fever Y. Elephantitiasis Z. Yellow fever 267. Many people in the Amish community exhibit polydactyly. The main factor contributing to this condition is W. Isolation* X. Natural selection Y. Pleiotropy Z. Convergent evolution 268. During translation, a genetic message carried in mRNA is read as a W. Sequence of base triplets or codons* X. Sequence of nucleotides Y. Sequence of amino acids Z. Poly A tail sequence of adenine nucleotides attached to the 3’ of ribosomal RNA 269. The main products of the light dependent phase of photosynthesis are W. Co2 and ATP X. H20 and NADPH Y. ATP and NADPH* Z. Oxaloacetic acid 270. A plant immersed in a hypotonic salt solution will W. Remain unchanged because of its cell wall X. Actively absorb metallic ions Y. Lose tugor Z. gain turgor* 271. Which enzyme is not involved with DNA replication? W. Synthetase* X. Primase Y. Polymerase Z. Helicase 272. An enzyme speeds up the rate of reaction by W. Establishing a concentration gradient X. Lowering the activation energy (Ea)* Y. Shifting equilibrium to the left Z. Increasing the number of active sites 273. Chlorine and iodine are elements found in Group VIIA of the periodic table. There are more chlorine compounds than iodine compounds because W. Chlorine atoms are more readily oxidized X. Iodine atoms are more readily reduced Y. Chlorine atoms have a greater atomic mass Z. Chlorine atoms have a greater electro-negativty* 274. Henle’s loop of a nephron functions as a counter-current multiplier because it W. Enhances active transport, thereby producing higher concentration differences that would not normally occur* X. Actively pumps out K+ ions, thus generating a concentration gradient Y. Helps produce urinary filtrate that is isotonic to the surrounding tissue Z. Inhibits the passive transport of water molecules 275. The process of deamination in the liver involves removal of an amine group and an atom of hydrogen from an amino acid to form W. Uric acid X. Ammonia* Y. Urea Z. Urobilinogen 276. The normal clotting time of blood is increased when there is a deficiency of vitamin W. K* X. C Y. E Z. D 277. Normal development of a vertebrate embryo includes programming of cell death by means of “suicide genes”. Programmed cell death in developing embryos is called W. Morphogenesis X. Palingenesis Y. Orthogenesis Z. Apoptosis* 278. An enzyme controlled reaction could overcome competitive inhibition by W. Decreasing temperature X. Excluding active sites to competitive substrates Y. Increasing substrate concentration* Z. Elevating pH 279. In angiosperms, the male gametophyte consists of W. A pollen grain X. A germinated pollen grain* Y. A microspore mother cell Z. An antheridium 280. A tissue that lines the lumen of ducts is W. Epithelial* X. Nervous Y. Adipose Z. Loose areolar 281. In a neuron, resting potential following an action potential is restored by W. Heightened activity of calcium ions within the cytoplasm X. Opening of voltage sensitive potassium channels and closing of sodium channels* Y. Repeated hyperpolarizations of the plasma membrane Z. Opening of sodium gates and release of cholinesterase 282. Which factors influence the distribution of biomes? W. Species diversity and carrying capacity X. Latitude and wind current patterns Y. Climate and topography* Z. Water current patterns and community succession 283. A structure of the cardiovascular system under the least hydrostatic pressure is W. A large artery X. A capillary Y. A vein Z. The right atrium* 284. A process that produces gametes with great diversity of gene combinations is W. Mitosis X. Synapsis* Y. Holoblastic cleavage Z. Meiotic reduction division 285. A chemical compound common to most cells is shown below. The diagram illustrates W. A nucleotide* X. A nucleoside Y. A nucleic acid Z. A nucleosome 286. The allantois of a bird embryo functions as W. A respiratory organ X. An excretory organ Y. Protection against shock Z. Both a respiratory and excretory organ* 287. The bonding of fatty acid molecules to a glycerol molecule, resulting in a lipid molecule requires W. The addition of a water molecule X. The removal of a carbonyl group Y. Glycosidic linkage Z. A hydroxyl group and a carbonyl group* 288. An evolutionary advantage of an organism with bilateral symmetry is W. A gastrovascular cavity X. A body cavity lined with coelom Y. Cephalization* Z. Two germ layers in embryonic development 289. The light dependent reactions of photosynthesis do not incude W. Cyclic and noncyclic pathways X. Electron acceptors P700 and P680 Y. Carbon dioxide as a source of carbon atoms* Z. Degradation of water to hydrogen ions and oxygen 290. An animal considered by scientists to be an intermediate form between the Insectivora and Primates is the W. Shrew* X. Bat Y. Sloth Z. Pika 291. The greatest primary productivity occurs in W. A continental lake X. An estuary* Y. A benthic biome Z. A grassland biome 292. Eukaryotic cells and prokaryotic cells are similar because both types possess W. A nuclear membrane X. A Golgi apparatus Y. Chromosomal RNA Z. A plasma membrane 293. The functional groups of many organic molecules determine their distinctive chemical and physical properties. Which functional group stabilizes the physical structure of proteins? W. Sulfhydryl group (-SH) X. Carboxyl group (-COOH) Y. Amino group (-NH2) Z. Phosphate group (-PO4) 294. Palisade cells within a plant leaf collectively make up the tissue called W. Sclerenchyma X. Collenchyma Y. Parenchyma* Z. Cambium 295. It is desirable to maintain a relatively high concentration of high density lipoproteins (HDL) in the blood in order to W. Maintain normal blood pressure within arteries X. Prevent cholesterol plaques in blood vessels* Y. Maintain a reserve of lipid molecules Z. Prevent blood clots in small blood vessels 296. Which set of parents are involved in a testcross? W. BB x Bb X. Bb x bb Y. BB x bb* Z. BB x BB 297. An organ of Corti is associated with the sensation of W. Tactile discrimination X. Sound* Y. Color vision Z. Olfactory discrimination 298. An organism that uses collar cells to create water currents, feeds on organic detritus, and is structured with spicules is most probably a W. Sponge* X. Hydra Y. Sea cucumber Z. Brittle star 299. When water undergoes a phase change from liquid to vapor, it involves breaking W. Ionic bonds X. Covalent bonds Y. Hydrogen bonds* Z. Van der Waals forces 300. Cytotoxic T cells, or killer cells, destroy virus infected cells and bacteria by W. Phagocytosis X. Secreting perforin* Y. Agglutination Z. Plasmolysis 301. Which is a polygenic trait in humans? W. Skin color* X. Schizophrenia Y. Cleft lip Z. Syndactyly 302. In a cell, hydrolysis of one ATP molecule W. Is an endergonic reaction X. Yields two ADP molecules Y. Releases a high energy bond* Z. Is anabolic 303. A eukaryotic cell has an endomembrane system that does not include W. The cytoskeleton* X. The Golgi apparatus Y. Lysosomes Z. The endoplasmic reticulum 304. Hydrogen ions that reduce NADP+ molecules to NADPH molecules during the light dependent reactions of photosynthesis come from W. The cytochrome complex X. Photolysis* Y. Electron carrier molecules Z. Photorespiration 305. Temperature regulation in endothermic animals is accomplished by a part of the brain called the W. Corpus callosum X. Hypothalamus* Y. Thalamus Z. Pons 306. In humans, the fight or flight response results from the activation of the W. Sympathetic division of the autonomic nervous system* X. Parasympathetic division of the autonomic nervous system Y. Limbic system Z. Adrenal cortex 307. A tissue lining the alveoli in the lungs that function as a permeable membrane is W. Simple squamous epithelia* X. Simple cuboidal epithelia Y. Transitional epithelia Z. Simple columnar epithelia 308. Interphase of cell division includes three subphases. The subphase in which replication occurs is the W. Prophase X. S phase* Y. G1 phase Z. G2 phase 309. In liver cells, peroxisomes secrete the enzyme catalase, which W. Destroys pathogens X. Deaminates excess amino acids Y. Uses hydrogen peroxide to detoxify harmful substances* Z. Activates Kupffer cells 310. Segmentation is an involuntary movement of the small intestine that W. Mixes chyme thoroughly with digestive juices* X. Takes over when peristalsis fails Y. Is controlled by the central nervous system Z. Works in conjunction with peristalsis 311. Studies show that the number of species in a community increases from the high latitudes toward the equator. It may be reasoned that species range is based on W. Chance migrations X. Tolerance for abiotic factors, such as temperature and light* Y. Tolerance for interspecific competition Z. A modified ecological niche 312. An arthropod considered a “living fossil” is the W. Horseshoe crab* X. Scorpion Y. Trilobite Z. Tick 313. An abiotic factor that is most important in determining the productivity of a terrestrial ecosystem is W. Light X. Water* Y. Temperature Z. Soil 314. A structural feature found in vertebrate chordates, but not in invertebrate chordates is W. Cephalization X. Pharyngeal gill slits Y. a postanal tail Z. A hollow dorsal nerve cord* 315. Which of the following does not facilitate the upward movement of water and dissolved minerals in the xylem vessels of a plant? W. Transpiration X. Turgor pressure* Y. Root pressure Z. Adhesion 316. The two forms of lactic acid are L-lactic acid and D-lactic acid. The two forms of lactic acid are called W. Structural isomers X. Enantiomers* Y. Geometric isomers Z. Right and left hydrocarbons 317. Intracellular connections found in animal cells could include W. Gap junctions and plasmodesmata X. Desmosomes and middle lamellae Y. Tight junctions and desmosomes* Z. Gap junctions and protein channels 318. Animal cells use a sodium-potassium pump in order to W. Maintain a membrane potential* X. Trigger an electrochemical impulse Y. Actively transport macromolecules across a membrane Z. Transform electrical charge to mechanical energy 319. T.H. Morgan and his associates made extensive use of fruit flies for their experiments mainly because W. The body cells of a fruit fly contain a small number of chromosomes* X. The fruit fly has a long life cycle Y. The fruit fly is oviviparous Z. Fruit flies produce offspring with unpredictable phenotypes 320. Which molecule ultimately provides the most energy for metabolic reactions W. NAD X. Acetyl CoA Y. NADPH* Z. FAD 321. Chemical analysis of the DNA of a ladybird beetle revealed that 30% of the nitrogenous bases consisted of adenine. What is the percentage of cytosine? W. 10% X. 20%* Y. 30% Z. 40% 322. Neuropeptides that are natural analgesics (pain killers) include W. Histamine and acetylcholine X. Endorphin and enkephalin* Y. Melatonin and angiotensin II Z. Dopamine and serotonin 323. In angiosperms, evolution of flower structure includes W. Fused petals* X. Fused carpels Y. Polyploidy Z. Lateral symmetry and superior ovaries 324. Countercurrent exchanges between the internal environment of an organism and its external environment are illustrated by W. Retention of heat in the feet of penguins standing on ice* X. Passage of air into the trachaea of a grasshopper Y. Elimination of ammonia from the gills of a lobster into water Z. Conversion of glucose into glycogen in the red muscles of mammals 325. A plant hormone that stimulates fruit ripening is W. Gibberellin X. Abscissic acid Y. Auxin Z. Ethylene* 326. Plant cells communicate with each other by W. Plasmodesmata, through which cytoplasm strands connect cells* X. Microtubules that connect one cell to another Y. Microfilaments that bind cells together Z. A middle lamella that glues cells together 327. The laboratory instrument used for cell fractionation is the W. Stereoscope X. Centrifuge* Y. Electrophoresis Z. Thin layer chromatography 328. Laboratory studies show that all aerobic species possess a respiratory pigment, called cytochrome C. This supports a theory of evolution proposed by W. Lamarck X. Darwin* Y. Sutton Z. Cuvier 329. Immunoglobulins (Igs) are antibody molecules that neutralize antigens at sites called W. CD4 molecules X. Loci Y. Active sites Z. Epitopes* 330. DNA technology, used in genetic engineering, includes all the following procedures except W. Colchicine administration* X. Restriction enzymes Y. Gel electrophoresis Z. Southern hybridization 331. At which stage of mitosis would cells be selected and microphotographed for the preparation of a karyotype? W. Interphase X. Prophase Y. Metaphase* Z. Anaphase 332. To properly prepare one liter of a one molar solution of glucose W. Dissolve one mole of glucose in enough distilled water to make one liter of solution* X. Dissolve one mole of glucose in a liter of distilled water Y. Dissolve 24 grams of glucose in a liter of solution Z. Dissolve 24 grams of glucose in a liter of distilled water 333. In which of the following ecosystems are nutrients cycled most rapidly? W. Temperate forest X. Tropical rain forest* Y. Estuary Z. Tundra 334. Photoperiodism is an important survival factor in a region called W. An abyssal plain X. A temperate forest* Y. A coral reef Z. A chaparral 335. Darwin’s finches on the Galapagos Islands are examples of evolution at work because they demonstrate W. Adaptive radiation* X. Convergent evolution Y. Speciation Z. Climatic shift 336. Which is the best example of a K-selected species? W. Pea plant X. Frog Y. Eel Z. Human* 337. Certain cells of the immune system release cytokines, which in turn, W. Activate B cells* X. Destroy intracellular pathogens Y. Stimulate production of interferons Z. Enhance the effects of killer T cells 338. Heart sounds are indicators of heart function. These sounds come primarily from W. Hydrostatic pressure in the atria X. Pacemaker impulses to the ventricles Y. Closure of all heart valves* Z. Opening of the aortic and pulmonary valves 339. Ganglions are groups of many cytons (cell bodies) located in the W. Central nervous system X. Peripheral nervous system* Y. Gray matter of the spinal cord Z. Corpus callosum 340. What is the chance of a couple having 4 sons in a row? W. 1/8 X. ¼ Y. ½ Z. 1/16* 341. Which of the following is the frozen desert? W. Taiga X. Tundra* Y. Chaparral Z. Grasslands 342. The most common type of population dispersion in nature is W. Random X. Clumped* Y. Uniform Z. Dispersive 343. Which is true about water potential? W. The water potential of pure water is negative X. The water potential of pure water is positive Y. The water potential of pure water is zero* Z. Water moves from a low water potential to a high water potential 344. Phototropisms in plants are controlled by W. Gibberellins X. Guard cells Y. Ethylene Z. Auxins* 345. The working of the Lac operon is important because W. It represents how mammals utilize lactose X. It represents a principle means by which genes are regulated in prokaryotes* Y. It is proof of semiconservative replication of DNA Z. It illustrates how RNA is processed after it is transcribed 346. What is the substrate of salivary amylase? W. Starch* X. Glucose Y. Protein Z. Amino acids 347. Which of the following has an open circulatory system? W. Lobster* X. Sponge Y. Human Z. Hydra 348. Which is not a cause of sympatric speciation? W. Geographic isolation* X. Polyploidy Y. Behavioral isolation Z. Mechanical isolation 349. Which of the following is an endocrine gland? W. Salivary gland X. Gallbladder Y. Lachrymal gland Z. Pineal gland* 350. Which best explains why the incidence of polydactyly is so much higher in the Amish population than in the rest of the population in the United States? W. Mutation X. Bottleneck effect Y. Founder effect* Z. Disruptive selection 351. Which of the following hormones controls metamorphosis in insects and crustaceans? W. Cortisol X. Adrenaline Y. Thyroxine Z. Ecdysone* 352. The threshold potential of a membrane of a neuron W. Is always 70mV X. Is always 90 mv Y. Can never change Z. Is a measure of the polarization of the membrane* 353. A Barr body is normally found in the nucleus of which kinds of cells? W. Somatic female cells* X. Sperm cells Y. Somatic male cells Z. Ova 354. Most energy during cellular respiration is harvested during W. The Krebs cycle X. Oxidative phosphorylation* Y. Glycolysis Z. Fermentation 355. The harmless viceroy butterfly resembles the poisonous monarch butterfly. This is an example of W. Mullerian mimicry X. Commensal coloration Y. Cryptic coloration Z. Batesian mimicry* 356. A man who is colorblind marries a woman with normal vision but whose father was colorblind. What is the chance they will have a colorblind child? W. 0% X. 25% Y. 50%* Z. 75% 357. The ATP produced during fermentation is generated by which of the following? W. Electron transport chain X. Substrate level phosphorylation* Y. Krebs cycle Z. Chemiosmosis 358. Which of the following would not normally diffuse through the lipid bilayer of a plasma membrane? W. CO2 X. Amino acid Y. Starch* Z. O2 359. Which of the following is present in a prokaryotic cell? W. Ribosomes* X. Mitochondria Y. Endoplasmic reticulum Z. Nuclear membrane 360. If a cell has 24 chromosomes at the beginning of meiosis, how many chromosomes will it have at the end of meiosis? W. 64 X. 48 Y. 24 Z. 12* 361. Which cellular organelle is the site of cellular respiration W. Golgi apparatus X. Mitochondria* Y. Endoplasmic reticulum Z. Ribosomes 362. Which term best describes how goslings recognize their mothers after they are hatched? W. Instinct X. Imprinting* Y. Reasoning Z. Habituation 363. Diatoms are the major primary producers in which of the following ecosystems? W. Marine* X. Desert Y. Chaparral Z. Tropical rain forest 364. In deer, fur length is controlled by a single gene with two alleles. When a homozygous deer with long fur is crossed with a homozygous deer for short fur, the offspring have fur of medium length. If these offspring with medium length fur mate, what percentage of their offspring will have long fur? W. 100% X. 75% Y. 50% Z. 25%* 365. All of the following are types of wastes excreted by animals except W. Ammonia X. Carbon dioxide Y. Uric acid Z. Nitrate* 366. During the course of which type of reaction is energy consumed? W. Hydrolysis X. Catabolic Y. Endergonic* Z. Oxidation-reduction (REDOX) 367. Consumption of CO2 can be used as a measure of photosynthetic rate because carbon dioxide is W. Consumed during the light reactions of photosynthesis X. Consumed during the dark reactions of photosynthesis* Y. Used to trap photons, the form of energy in sunlight Z. Necessary for the production of ATP in oxidative phosphorylation 368. In animal development, all of the following occur except W. Cleavage, a succession of rapid cell divisions, occurs just after fertilization X. The zygote develops polarity Y. The zygote develops into a blastula Z. All of the genes in the zygote are activated* 369. Which of the following describes a protein capable of converting related proteins to an infectious form? W. Prion* X. Viroid Y. Virus Z. Spirochete 370. The domain Archaea contains prokaryotic organisms that W. Possess a nuclear envelope X. Live in extreme heat or acid environments* Y. Have plant-like features Z. Reproduce sexually 371. Which statement best describes the action of the hormone oxytocin in humans? W. It stimulates growth X. It stimulates the secretion of epinephrine Y. It stimulates contraction of the uterus* Z. It increases oxygen levels in the blood 372. Which of the following areas is a site of active cell division at the tips of plant roots and shoots? W. Lateral meristems X. Apical meristems* Y. Pericycle Z. Cortex 373. Which substances are components of the plasma membrane of a cell? W. Glycoproteins* X. Cytochromes Y. Nucleic acids Z. Phosphatidic acid 374. Mitosis in vertebrate cells occurs just after which of the following phases of the cell cycle? W. G1 X. S Y. G2* Z. M 375. Certain cells of all of the following organisms undergo meiosis except W. Ferns X. Bacteria* Y. Fungi Z. Nematodes 376. Water and minerals flow up through a plant through the W. Tracheids and vessel elements of xylem* X. Tracheids and vessel elements of phloem Y. Sieve tubes of xylem Z. Sieve tubes of phloem 377. In plants, change in the level of which of the following substances causes the stomata to close and conserve water during drought? W. Brassinosteroids X. Abscisic acid* Y. Auxin Z. Ethylene 378. O2 and CO2 diffuse from resions where their partial pressures W. Are higher to regions where they are lower* X. Are lower to regions where they are higher Y. Are zero to regions of higher partial pressure Z. Are zero to regions of lower partial pressure 379. It is theorized that when organisms that were capable of self-replicating originated, Earth’s atmosphere contained a low concentration of W. Water X. Gaseous oxygen* Y. Carbon dioxide Z. Nitrogen 380. The composition of lymph in lymph vessels is roughly the same as W. Interstitial fluid* X. Glomerular filtrate Y. Blood Z. Chyme 381. In photosynthesis, most ATP is produced as a result of which of the following processes? W. The light reactions X. The dark reactions Y. Noncyclic photophosphorylation* Z. The Calvin cycle 382. Which of the following organisms is not usually considered alive because of its dependence on other organisms for reproduction? W. Nematode X. Tapeworm Y. Lichen Z. Virus* 383. In guinea pigs, black fur (B) is dominant to brown fur (b) and no tail (T) is dominant over tail (t). What fraction of the progeny of the cross BbTt x BbTt will have black fur and tails? W. 1/16 X. 3/16* Y. 3/8 Z. 9/16 384. A migrating flock of Canada geese is nearly decimated by a severe storm. Only four members of the flock, which constitute the entire population of a specific region, survive and return north the next spring. These four start a new colony. This phenomenon is known as W. The founder effect X. Natural selection Y. Polymorphism Z. The bottleneck effect* 385. Which of the following describes a drawing showing the evolutionary history among a particular species or a group of related species? W. Food web X. Punnett square Y. Pedigree Z. Phylogenetic tree* 386. Which of the following characteristics is common to all bryophytes? W. Large, independent gametophytes* X. Monoecious plants Y. Haploid spores Z. Vascular tissue 387. Allolactose stimulates the cells of the human body to produce mRNA’s that code for the enzyme β-galactosidase, which breaks down lactose into glucose and galactose. In this case, the role of allolactose can best be described as that of a W. DNA replication stimulator X. Translational inhibitor Y. Stimulator of β-galactosidase secretion Z. Regulator of gene activity* 388. Which of the following type of data can be used to map the locations of genes on chromosomes? W. Segregation frequency X. Rate of gene regulation Y. Rate of gene recombination* Z. Rate of gene expression 389. All of the following are evidence for evolution except W. The presence of anatomical homologies X. Vestigial organs Y. The existence of molecular homologies Z. The existence of homologies in diet among species* 390. The movement of H+ across the inner mitochondrial membrane during chemiosmosis of cellular respiration, is an example of what type of movement across a membrane? W. Active transport X. Facilitated diffusion Y. Symport Z. Antiport 391. Which of the following is a major food source for organisms that live in the benthic zone? W. Floating aquatic plants X. Phytoplankton Y. Zooplankton Z. Detritus* 392. Which of the following cells would most likely have the greatest concentration of mitochondria in its cytoplasm? W. A cell lining the digestive tract X. An active skeletal muscle cell* Y. A cell in the liver Z. A cell in the lung 393. Which of the following evolved before algae? W. Bacteria* X. Hydras Y. Cnidarians Z. Fungi 394. Insertions and deletions may cause which of the following types of mutation? W. Missense X. Nonsense Y. Base-pair substitution Z. Frameshift* 395. The stomata – the openings on the underside of a plant leaf through which carbon dioxide is taken up and oxygen is expelled – are opened as a result of W. Movement of mesophylls away from the stomatal opening X. Increased turgidity in the guard cells* Y. Decreased turgidity in the guard cells Z. Elongation of the guard cells toward the mesophyll 396. Which characteristic is not required of a population in Hardy-Weinberg equilibrium? W. The population must be very large X. There must be no migration into or out of the population Y. The members of the population must be mating randomly Z. There must be only two alleles present for each characteristic in the population* 397. In plants that undergo alternation of generations, the gametophyte stage is always W. Unicellular X. A seed Y. Diploid Z. Haploid* 398. Bacteria reproduce by which of the following processes? W. Binary division X. Binary fission* Y. Mitosis Z. Meiosis 399. In plants, the abscission, or dropping of leaves is triggered by changes in W. Cytokinin X. Ethylene* Y. Abscisic acid Z. Brassinosteroids 400. Gel electrophoresis can be used for which of the following laboratory procedures? W. Determining the molecular weight of proteins and nucleic acids X. Determining the charge of proteins and nucleic acids Y. Separating nucleic acids and proteins on the basis of their size* Z. Separating nucleic acids and proteins on the basis of their charge LAB QUESTIONS Lab #1 Diffusion & Osmosis 1. In beaker B, what is the water potential of the distilled water in the beaker, and of the beet core? W. Water potential in the beaker = 0; water potential in the beet core = 0 X. Water potential in the beaker = 0; water potential in the beet core = -0.2* Y. Water potential in the beaker = 0; water potential in the beet core = 0.2 Z. Water potential in the beaker cannot be calculated; water potential in the beet core = 0.2 2. Which of the following statements is true for the diagrams? W. The beet core in beaker A is at equilibrium with the surrounding water* (Both are 0) X. The beet core in beaker B will lose water to the surrounding environment Y. The beet core in beaker B would be more turgid than the beet core in beaker A Z. The cells in beet core B are likely to undergo plasmolysis Lab #2 Enzyme Catalysis 3. In order to keep the rate of reaction constant over the entire time course, which of the following should be done? W. Add more enzyme X. Gradually increase the temperature after 60 seconds Y. Add more substrate* Z. Add H2SO4 after 60 seconds 4. What is the role of sulfuric acid (H2SO4) in this experiment? W. It denatures the enzyme by altering the active site* X. It is a competitive inhibitor and blocks the active site of the enzyme Y. It is the substrate on which catalase acts Z. It binds with the remaining hydrogen peroxide during titration 5. A student was performing a titration for this laboratory and accidentally exceeded the endpoint. What would be the best step to obtain good data for this point? W. Estimate the amount of KMnO4 that was in excess and subtract this from the result X. Repeat titration using reserved remaining sample* Y. Obtain data for this point from another lab group Z. Prepare a graph of the data without this point and then read the estimated value from the graph. Lab #3 Mitosis & Meiosis 6. Which of the following statements is correct? W. Crossing over occurs in prophase I of meiosis and metaphase of mitosis X. DNA replication occurs once prior to mitosis and twice prior to meiosis Y. Synapsis occurs in prophase of mitosis Z. Karyokinesis occurs once in mitosis and twice in meiosis* 7. The cell cycle in a certain type has a duration of 16 hours. The nuclei of 660 cells showed 13 cells in anaphase. What is the approximate duration of anaphase in these cells? W. 2 minutes X. 13 minutes Y. 19 minutes* (13 / 660 total cells = 2%) 0.02 x 960 = ~ 19 D. 32 minutes 8. A group of asci formed from crossing light spored Sordaria with dark spored produced the following results How many of these asci contain a spore arrangement that resulted from a crossing over? W. 3 X. 7 Y. 8 Z. 10* (# of spores of all asci counted) 9. From this small sample, calculate the map distance between the gene and centromere. W. 10 map units X. 20 map units* (# of crossovers / total # asci x 100 /2) Y. 30 map units Z. 40 map units Lab #4 Plant Pigments and Photosynthesis 10. What is the Rf value for carotene calculated from the chromatogram below? W. 1.09 X. 0.17 Y. 0.96* (distance pigment moves/ distance solvent moves) 11.5/12=0.96 Z. 0.33 11. For the chromatogram shown, W. The Rf for chlorophyll b can be determined by dividing the distance the green pigment migrated by the distance the solvent front migrated* X. The Rf value of chlorophyll b will be higher than the Rf value for chlorophyll a Y. The molecules of xanthophyll are not easily dissolved in this solvent, and thus are probably larger in mass than the chlorophyll b molecules Z. If this same chromatogram were set up and run for twice as long, the Rf values would be twice as great for each pigment. 12. What is the role of DPIP in this experiment? W. It mimics the action of chlorophyll by absorbing light energy X. It serves as an electron donor and blocks the formation of NADPH Y. It is an electron acceptor and is reduced by electrons from chlorophyll* Z. It is bleached in the presence of light and can be used to measure light levels. 13. Some students were not able to get many data points in this experiment because the solution went from blue to colorless in only 5 minutes for the unboiled chloroplasts exposed to light. What modifications to the experiment do you think would be most likely to provide better results? W. Increase the number of drops of chloroplasts used from three to five X. Double the volume of DPIP so that the solution has a lower transmittance* Y. Use fresher spinach and prepare the chloroplast solution during the lab procedure Z. Modify the blank so that the initial transmittance is higher 14. If a student performed this experiment and got a flat curve, showing very little change in percent transmittance over time, which of these would be the most plausible explanation? W. The DPIP was too pale at the beginning of the experiment X. The chloroplast solution was too concentrated Y. The experimenter used chloroplasts that were damaged and could not respond to light* Z. The blank was not properly used to calibrate the spectrophotometer. Lab #5 Cell Respiration 15. What is the rate of oxygen consumption in the germinating corn at 12°C as shown in the graph? W. 0.08 ml/min X. 0.04 ml/min* (ΔY/ΔX) Y. 0.8 ml/min Z. 0.6 ml/min 16. Using figure 5.2, which of the following is a true statement based on the data? W. The amount of oxygen consumed by germinating corn at 22°C is approximately twice the amount of oxygen consumed by germinating corn at 12°C* X. The rate of oxygen consumption is the same in both germinating and non-germinating corn during the initial time period from 0 to 5 minutes Y. The rate of oxygen consumption in the germinating corn at 12°C at 10 minutes is 0.4 mlO2/minute Z. If the experiment were run for 30 minutes, the rate of oxygen consumption would decrease 17. Which of the following conclusions is supported by the data shown on the graph? W. The rate of respiration is higher in nongerminating seeds than in germinating seeds X. Nongerminating seeds are not alive and show no difference in rate of respiration at different temperatures Y. The rate of respiration in the germinating seeds would have been been higher if the experiment were conducted in sunlight Z. The rate of respiration increases as the temperature increases in both germinating and nongerminating seeds* 18. What is the role of KOH in this experiment? W. It serves as an electron donor to promote cellular respiration X. As KOH breaks down, the oxygen needed for cellular respiration is released Y. It serves as a temporary energy source for the respiring organism Z. It binds with carbon dioxide to form a solid, preventing CO2 production from affecting gas volume* Lab #6 Molecular Biology 19. How many base pairs is the fragment circled in figure 6.4? W. 350 X. 22 Y. 2200 Z. 3500* 20. Which of the following statements is correct? W. Longer DNA fragments migrate farther than shorter fragments X. Migration distance is inversely proportional to the fragment size* Y. Positively charged DNA migrates more rapidly than negatively charged DNA Z. Uncut DNA migrates farther than DNA cut with restriction enzymes 21. Which lane shows a digest with BamHI only? W. I X. II Y. III* Z. IV 22. Which lane shows a digest with both BamHI and EcoRI? W. I X. II Y. III Z. IV* 23. On which petri dish do only transformed cells grow? W. Plate I X. Plate II* Y. Plate III Z. Plate IV 24. Which of the plates is used as a control to show that non-transformed E. coli will not grow in the presence of kanamycin? W. Plate I X. Plate II Y. Plate III Z. Plate IV* 25. If a student wants to verify that transformation has occurred, which of the following procedures should they use? W. Spread cells from Plate I onto a plate with LB agar; incubate X. Spread cells from Plate II onto a plate with LB agar; incubate Y. Spread cells from Plate III onto a plate with LB agar and also onto a plate with LB agar with kanamycin; incubate Z. Spread cells from plate III onto a plate with LB agar with kanamycin; incubate* 26. During the course of an E coli transformation laboratory, a student forgot to mark the culture tube that received kanamycin resistant plasmids. The student proceeds with the laboratory because they think that they will be able to determine from the results which culture tube contained cells that may have undergone transformation. Which plate would be most likely to indicate transformed cells? W. A plate with a lawn of cells growing on LB agar with kanamycin X. A plate with a lawn of cells growing on LB agar without kanamycin Y. A plate with 100 colonies growing on LB agar with kanamycin* Z. a plate with 100 colonies growing on LB agar without kanamycin Lab # 7 Genetics of Organisms 27. On the basis of the results shown in the table, which statement is most likely true? W. The genes for red eyes and normal wings are linked X. The gene for no wings is sex-linked Y. The gene for red eyes and the gene for no wings are both dominant D. The gene for eye color is inherited independently of the gene for wings* 28. Based on the hypothesis that this is a dihybrid cross, with the two genes unlinked, calculate (𝑥 2 ) chi-square using the data in the table of observed phenotypes. W. 6.04 X. 7.81 Y. 4.98* Z. 24.0 29. Compare the chi-square value obtained in question #3 with the critical values table below for p=0.05. Which of the following statements would be true? W. Since the calculated value for chi-square is less than 7.82, the results support the hypothesis that the parents are heterozygous for two unlinked traits* X. Since the calculated value for chi-square is less than 7.82, the results support the hypothesis that eye color and wings are linked Y. Since the calculated value for chi-square is less than 7.82, the results are inconclusive. The experiment should be repeated Z. Since the calculated value for chi-square is so large, the variations from the experiment are excessive. The experiment should be repeated. Probability (p) 0.05 0.01 0.001 Degrees 1 3.84 6.64 10.8 of 2 5.99 9.21 13.8 Freedom 3 7.82 11.3 16.3 (df) 4 9.49 13.2 18.5 5 11.1 15.1 20.5 Lab #8 Population Genetics and Evolution 30. If the frequency of two alleles in a gene pool is 90% A and 10% a, what is the frequency of individuals in the population with the genotype Aa? W. 0.81 X. 0.09 Y. 0.18* Z. 0.01 31. If a population experiences no migration, is very large, has no mutations, has random mating, and there is no selection, which of the following would you predict? W. The population will evolve, but much more slowly than normal X. The makeup of the population’s gene pool will remain virtually the same as long as these conditions hold* Y. The composition of the population’s gene pool will change slowly in a predictable manner Z. The population probably has an equal frequency of A and a alleles 32. In a population that is in Hardy-Weinberg equilibrium, the frequency of the homozygous recessive genotype is 0.09. What is the frequency of individuals that are homozygous for the dominant allele? W. 0.7 X. 0.21 Y. 0.42 Z. 0.49* Lab #9 Transpiration 33. All of the following enhance water transport in terrestrial plants except W. Hydrogen bonds linking water molecules X. Capillary action due to adhesion of water molecules to the walls of the xylem Y. Evaporation of water from the leaves Z. K+ being transported out of the guard cells* 34. Under conditions of bright light, in which part of a transpiring plant would water potential be the lowest? W. Xylem vessels in the roots X. Xylem vessels in the leaves Y. Root hairs Z. Spongy mesophyll of the leaves* For questions 35-38 refer to figure 9.6. 35. Name tissue type A and describe its function Structure ________________________________________________Epidermis Function _________________________________________________Protection 36. Name tissue type B and describe its function Structure ________________________________________________Phloem Function __________________________________________________Food transport 37. Name tissue type C and describe its function Structure ________________________________________________Xylem Function _________________________________________________Water transport 38. Name tissue type D and describe its function Structure ________________________________________________Parenchyma Function __________________________________________________Store food Lab #10 Physiology of the Circulatory System 39. Which of the following has the least effect on blood pressure in a young adult? W. Temperature of the room* X. Position of the body Y. Level of conditioning Z. Supplemental vitamins 40. An individual’s blood pressure is reported as 110/50. Which of the following is correct? W. The pressure during the contraction phase of the heart is 50 and the pressure during the relaxation phase is 110 X. Systolic pressure is 110 and diastolic pressure is 50* Y. The pulse is 110 during exercise and 50 when at rest Z. The individual shows possible borderline high blood pressure 41. Which of the following organisms would show the greatest fluctuation in body temperature hour by hour? W. Dolphin X. Mouse Y. Lake trout Z. Rattlesnake* 42. What is the relationship between metabolic rate and body temperature in Daphnia? W. As the body temperature increases, the metabolic rate decreases X. An increase of 10°C results in a doubling of metabolic rate* Y. Heart rate increases as body temperature decreases Z. Cellular enzymes are less active at 35°C than at 20°C, resulting in decreased metabolic rate 43. If Q10 = 2, then an enzymatic reaction that takes place at a given rate at 7°C would take place approximately how many times faster at 27°C? W. Twenty times X. Eight times Y. Four times* Z. Three times Lab # 11 Animal Behavior A group of students wanted to study the effect of nitrogen fertilizer on plant growth, so they took two similar plants and set them on a window sill for a two week observation period. They watered each plant the same amount, but gave one a small dose of fertilizer with each watering. They collected data by counting the total number of new leaves on each plant and also measured the height of each plant in centimeters. 44. Which of the following is a significant flaw in this experimental setup? W. There is no variable factor X. There is no control Y. There is no repetition* Z. Measurable results cannot be expected Students placed five pillbugs on the dry side of a choice chamber and five pillbugs on the wet side. They collected data as to the number on each side every 30 seconds for 10 minutes. After 6 minutes, eight or nine pillbugs were continually on the wet side of the chamber, and several were under the filter paper. 45. Which of the following is not a reasonable conclusion from these results? W. It takes the pillbugs several minutes to explore their surroundings and select a preferred habitat. X. Pillbugs prefer a moist environment Y. Pillbugs prefer a dark environment Z. Pillbugs demonstrate no significant habitat preference* (No control so any would work) 46. If a student wanted to determine whether pillbugs prefer a moist or dry environment, what would be the best way to analyze data from the experiment? W. Total the number of pillbugs on the dry side throughout the entire experiment and compare this with the number on the wet side throughout the experiment X. After waiting five minutes for the pillbugs to acclimate, count the number of pillbugs on the dry side every 30 seconds for five minutes. Total and average the results, and compare this with the number of pillbugs on the wet side during this same time interval.* Y. Compare the number of pillbugs on the dry side at the end of 10 minutes with the number of pillbugs on the wet side at the end of 10 minutes Z. Divide the number of pillbugs on the dry side throughout the experiment by the number on the wet side throughout the experiment 47. Which of the following hypotheses is stated best? W. If pillbugs are allowed free movement, then more will be found in a moist environment than in a dry environment* X. If pillbugs like a moist environment, then they will move to the wet side of a choice chamber Y. If an experiment with pillbugs is run for 10 minutes, then more pillbugs will be found in the most favorable environment Z. Pillbugs are found in moist habitats, so I predict that more will be found where it is wet Lab #12 Dissolved Oxygen and Aquatic Primary Productivity 48. What is the percent oxygen saturation for a water sample at 25°C that has 7 mg O2/l? W. 65%* X. 48% Y. 35% Z. 100% 49. In which aquatic environment would you expect dissolved oxygen to be highest? W. A mountain lake that is clear and cold X. A bog where the water is shallow and warm and there is a mat of aquatic plants Y. A marine tidepool Z. A cold mountain stream dropping over a series of small rock falls* Study figure 12.3 to answer the following question 50. At what light intensity do you expect there to be no net productivity? W. Any intensity below 100% X. Only at intensities of 0% and 2% Y. Any intensity below 10%* Z. Any intensity above 25% 51. What is meant by “net productivity” and how is it calculated in a sample aquatic environment? W. It is a measure of the organic products of photosynthesis that accumulate after cellular respiration by those organisms is taken into account, and it is calculated by subtracting the amount of oxygen in the dark bottle from the amount in the light bottle* X. It is a measure of the amount of respiration in a test area, and it is calculated by subtracting the amount of oxygen present in the light bottle from the amount in the dark bottle Y. It is the total amount of carbon fixed, and it is calculated by measuring the amount of oxygen present in a bottle kept in the light Z. It is the amount of oxygen produced during the day, and it is calculated by subtracting the amount of oxygen in the light bottle from the amount in the dark bottle A biology class used two aquatic cultures as described below for the experiment with screens that reduce light. They measured dissolved oxygen initially and then after 24 hours. Culture A Little phytoplankton Rich in zooplankton Low initial dissolved oxygen Culture B Rich in phytoplankton Rich in zooplankton High initial dissolved oxygen 52. What results would you predict for this experiment? W. The net productivity in culture A will be much higher than that in culture B X. Culture B will have both higher gross productivity and higher net productivity than culture A* Y. The net productivity for culture A will be negative at greater light intensity than that for culture B Z. Cultures A and B will show similar results because of the comparable quantities of zooplankton