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Choose the response which best completes each of the following statements or answers each of the following questions. 1. Plastids bear a striking similarity to mitochondria in that plastids (1.) store carbohydrates, fats, and proteins (2.) synthesize green, red, and yellow pigments (3.) are found in photosynthetic organisms only (4.) contain DNA, RNA, and ribosomes 2. Which carbohydrate is usually NOT present in animal cells and tissues? (1.) glucose (2.) glycogen (3.) fructose (4.) cellulose (5.)lactose 3. The evolution of the eukaryotes required the development of (1.) free ribosomes (2.) functioning mitochondria (3.) membrane bound organelles (4.) an activated Golgi body 4. The bond between two amino acids in a protein is called (1.) a glycosidic bond (2.) an ester bond (3.) an ionic bond bond (4.) a peptide 5. A protein may be denatured by (1.) hydrolysis (2.) heat or heavy metals (3.) action of enzymes (4.) assimilation (5.) dehydration synthesis 6. There is good evidence of linkage when (1.) genes of two different loci segregate independently (2.) genes of two different alleles do not segregate independently (3.) a gene is invariably associated with a specific characteristic (4.) two genes invariably work to control the expression of a single characteristic (5.) two genes are located together in a single gamete 7. The organelles most closely associated with the intracellular digestion of damaged cellular components are (1.) peroxisomes (2.) mesosomes (3.) glyoxysomes (4.) dictysomes (5.) lysosomes Each of the numbered items refer to the numbered statements that follow. Select the one numbered choice which best fits each statement. A choice may be used once, more than once, or not at all. Questions 8-9 (1.) (2.) (3.) (4.) (5.) Pleiotropy Multiple Alleles Sex linkage Linked genes Independent Assortment 8. This is the mode of inheritance of the ABO blood group. 9. This is the mode of inheritance of hemophilia. 10. A structure found commonly in animal cells but rarely in plant cells is the(1.) Golgi apparatus (2.) centriole (3.) nucleus (4.) endoplasmic reticulum (5.) mitochondrion 11. A student examining a cell under the microscope noticed the formation of a cell plate in the midline of the cell and the formation of nuclei at the poles of the cell. The cell under examination was most likely (1.) an animal cell in the M phase of the cell cycle (2.) a dividing bacterial cell (3.) a plant cell undergoing cytokinesis (4.) an animal cell undergoing cytokinesis (5.) a plant cell in the anaphase stage 12. Which discovery provides the best evidence to support the belief that DNA carries genetic information? (1.) Heritable transformation of bacterial cells is brought about by DNA. (2.) The DNA content from cells of different tissues of an organism is the same. (3.) The adenine to thymine and guanine to cytosine ratios in DNA are equal to 1. (4.) DNA is present in chromosomes. (5.) DNA is present in all cells that divide. 13. In guinea pigs, black is dominant. One-half of a particular litter is white. If it is assumed the laws of chance operate, the parent cross was most likely (1.) BB X Bb (2.) Bb X Bb (3.) Bb X bb (4.) bb X bb (5.) BB X bb 14. To determine whether an unknown black guinea pig is pure or hybrid, it should be crossed with (1.) a white (2.) a hybrid black (3.) a hybrid white (4.) a pure black (5.) another unknown 15. Which set of parents could NOT be the parents of a child with type O blood? (1.) Father type A, mother type O (2.) Father type A, mother type B (3.) Father type B, mother type O (4.) Father type AB, mother type O (5.) Father type O, mother type O 16. Which is true of a gene that is dominant? (1.) It is usually detrimental. (2.) It will occur more frequently than its recessive allele. (3.) It will occur less frequently than its recessive allele. (4.) It will have the same phenotypic effect whether it appears in the homozygous or heterozygous condition. 17. Phenylketonuria is a disease caused by a single gene defect. Unlike sickle-cell anemia, it can be treated by (1.) controlling the diet of PKU infants (2.) using vaccines to counteract the effect of the mutant gene (3.) correcting the mutant gene by genetic engineering (4.) applying low-level radiation doses to affected cells (5.) using the "wet diaper" test at stated intervals 18. Chromosomes do NOT occur in pairs in (1.) body cells (2.) somatic cells (3.) fertilized eggs (4.) gametes (5.) zygotes 19. Osmosis is a process that (1.) involves the movement of particles from saturated solutions (2.) moves water molecules from an area of higher concentration to an area of lower concentration, using energy (3.) equalizes the concentration of particles by the movement of water molecules (4.) continues until the medium on each side of the membrane has become hypertonic (5.) regulates the tonicity on either side of the membrane 20. The endoplasmic reticulum functions as (1.) a network that binds cells together (2.) an ultrastructural framework in the cytoplasm (3.) a secretory and storage syncytium (4.) a network of fibers to which the nucleoli are attached (5.) a control center for protein synthesis 21. In plants, the plastids which contain pigments that give fruit, flowers, and autumn leaves their orange and yellow colors are known as (1.) epiblasts (2.) leucoplasts (3.) amyloplasts (4.) chloroplasts (5.) chromoplasts 22. A primary reason for Mendel's success in his studies of pea plant inheritance was that (1.) he was the first person to attempt studies of inheritance (2.) there was plenty of room in his garden (3.) he studied one trait at a time (4.) he concentrated on the whole organism (5.) he was the first to postulate the gene theory 23. A change affecting the base sequence in an organism's DNA is known as (1.) replication (2.) chromosomal mutation (3.) transcription (4.) independent assortment (5.) gene mutation The following directions apply to questions 24-26 which follow in the question blocks. --------------------------------------------------------------------------Each set of numbered choices refers to the numbered words or statements that follow it. Choose the numbered choice that best fits each word or statement. A choice may be used once, more than once, or not at all. Choices (1.) (2.) (3.) (4.) (5.) DNA molecules only RNA molecules only Both DNA and RNA molecules Neither DNA or RNA molecules ATP molecules only 24. Molecules composed of chains of nucleotides. 25. Molecules found in the nucleus of the cell. 26. Molecules that carry genetic information from the nucleus to the ribosomes. ---------------------------------------------------------------------Choices (1.) (2.) (3.) (4.) (5.) (6.) Mutation Sex Linked recessive Hybrid vigor Inbreeding Codominance gene linkage 27. Radiation can cause definite structural changes in the DNA molecules of chromosomes. 28. Hemophilia and colorblindness are carried on the X chromosome. 29. The alleles for two different traits are inherited together on the same chromosome. 30. Biologists have discovered that a certain type of poison interferes with protein synthesis. Which cell structure listed is most likely affected by the poison? (1.) cytoplasm (2.) ribosome (3.) centrosome (4.) vacuole (5.) mitochondrion 31. According to the fluid mosaic model of the plasma membrane, proteins are (1.) spread out in a continuous layer over both membrane surfaces (2.) located in the hydrophilic layer of the membrane (3.) converted to glycogen by the hormone insulin in the peroxisomes (4.) capable of leaving the membrane and dissolving in the solution of the external environment (5.) embedded in the lipid bilayers 32. A couple whose family indicates chromosomal genetic disorders seeks genetic counseling. Which procedure would provide them with the genetic information that would help them to plan a family? (1.) karyotyping (2.) electrophoresis (3.) cloning (4.) genetic engineering (5.) amniocentesis 33. Which is NOT associated with cell division in animals? (1.) Duplication of chromosomes (2.) Constriction of dividing cells (3.) Separation of chromosomes (4.) Spindle fibers (5.) Cell plate formation 34. An enzyme that has two binding sites and exists in two or more conformations is known as (1.) a hydrolytic enzyme (2.) an allosteric enzyme (3.) a catalytic enzyme (4.) a catabolic enzyme (5.) an anabolic enzyme 35. The process of transcription occurs in the (1.) mitochondrion (2.) ribosome (3.) cytoplasm (4.) polysome (5.) nucleus 36. Which disorder is the result of meiotic nondisjunction? (1.) PKU (2.) hemophilia (3.) Tay-Sachs disorder (4.) Down syndrome (5.) Sickle-cell anemia 37. Which occurs during meiosis but not during mitosis? (1.) Chromosomes align at the metaphase plate (2.) Chromosomes condense (3.) Chromosomes migrate to opposite poles (4.) A spindle apparatus forms (5.) Synapsis Base your answers to questions 38 and 39 which follow on the basis of the following paragraph and your knowledge of biology. Sickle-cell anemia occurs in two forms, major and minor. The major form is usually fatal in childhood while the minor form is much less severe. Normal persons are pure for the normal gene. Persons with the major form are pure for the abnormal gene. Persons with the minor form are hybrid. 38. If both parents have the minor form, what percent of their children are expected to be normal? (1.) 0% (2.) 25% (3.) 50% (4.) 75% (5.) 100% 39. Which type of inheritance is illustrated by this paragraph? (1.) complete dominance (2.) incomplete dominance (3.) codominance (4.) sex linkage (5.) multiple genes 40. In garden pea plants, tallness is dominant over shortness, and yellow seeds are dominant over green seeds. If a pea plant which is hybrid for tallness and hybrid yellow seeds is crossed with a pea plant which is heterozygous for tallness and heterozygous for yellow seeds, what proportion of the offspring would be likely to be short with green seeds? (1.) 1/16 (2.) 1/8 (3.) 1/4 (4.) 1/2 (5.) 9/16 41. As a result of crossing two hybrid yellow garden peas, 120 offspring are produced. According to the laws of chance, the most probable number of yellow offspring is (1.) 0 (2.) 30 (3.) 60 (4.) 90 (5.) 120 42. One hundred experimental matings of brown birds with white birds produced speckled offspring. The mating of two speckled birds would probably result in (1.) 75% white, 25% brown (2.) 25% brown, 75% white (3.) 100% speckled (4.) 25% brown, 50% speckled, 25% white (5.) 50% brown, 25% white, 25% speckled 43. When light strikes chlorophyll molecules, they lose electrons, which are ultimately replaced by (1.) splitting water (2.) breaking down ATP (3.) removing them from NADPH (4.) fixing carbon (5.) oxidizing glucose 44. The overall function of the Calvin cycle is (1.) capturing sunlight (2.) making sugar (3.) producing carbon dioxide (4.) splitting water (5.) oxidizing glucose 45. What is rubisco? (1.) the enzyme in C3 plants that first captures CO2 to begin the Calvin cycle (2.) the enzyme responsible for splitting H2O to produce O2 in photosynthesis (3.) the enzyme that forms a 4-carbon compound in CAM metabolism (4.) the first stable intermediate in CAM metabolism (5.) the 5-carbon sugar molecule that reacts with CO2 to begin the Calvin cycle 46. Which of these wavelengths is least useful for photosynthesis? (1.) green (2.) yellow (3.) blue (4.) orange (5.) red 47. (1.) (3.) (4.) (5.) What is formed when pyruvate is converted to acetyl CoA? CO2 and ATP are formed (2.) CO2 and NADH are formed CO2 and coenzyme A are formed one turn of the Krebs cycle is completed (oxidized) NAD is regenerated 48. During respiration in a eukaryotic cell, reactions of glycolysis occur, or are located, in or on (1.) the cytosol (2.) the matrix of the mitochondrion (3.) the cristae of the mitochondrion (4.) the intermembrane space of the mitochondrion (5.) across the inner membrane of the mitochondrion 49. Sports physiologists at the E-KCS training center wanted to monitor athletes to determine at what point their muscles were functioning anaerobically. They could do this by checking for a buildup of (1.) ATP (2.) lactate or lactic acid (3.) carbon dioxide (4.) ADP (5.) oxygen 50. During respiration in a eukaryotic cell, the electron transport chain is located in or on the (1.) cytosol (2.) matrix of the mitochondrion (3.) cristae of the mitochondrion (4.) intermembrane space of the mitochondrion (5.) none of the previous 51. The enzyme ATP synthase forms ATP (1.) due to the potential energy of a concentration gradient of hydrogen ions across a membrane (2.) due to substrate-level phosphorylation (3.) from glucose in the absence of oxygen (4.) in the absence of chemiosmosis 52. In the Krebs cycle, the energetic production per glucose molecule is (1.) 2 ATP, 6 NADH, 2 FADH2 (2.) 38 ATP (3.) 4 ATP, 8 NADH (4.) 2 ATP, 6 NADH (5.) ATP, 3 NADH, 1 FADH2 53. A major reason pH can affect enzyme activity because (1.) most substrates don't function well at high or low pH (2.) high or low pH may disrupt hydrogen bonding and change the shape of the active site (3.) high or low pH may cause the active site to lose its energy (4.) excess hydrogen ions can combine with the substrate and cause the reaction to go more slowly (5.) hydrogen ions absorb energy and thus there may not be enough energy to get the reaction started. 54. (1.) (2.) (3.) (4.) (5.) Which chemical components make up a nucleotide? a nitrogenous base, an amino acid, and a pentose sugar a nitrogenous base, an amino acid, and a phosphate group a nitrogenous base, a phosphate group, and a pentose sugar a nitrogenous base, a fatty acid, and an amino acid a series of nitrogenous bases and a sugar-phosphate backbone 55. Which level of protein structure are best represented by the alpha helix and pleated beta sheet? (1.) primary structure (2.) secondary structure (3.) tertiary structure (4.) quaternary structure (5.) pentiary structure 56. Estrogen, progesterone, and testosterone belong to which class of molecules? (1.) proteins (2.) amino acids (3.) lipids (4.) carbohydrates (5.) nucleic acids 57. What is meant by the induced fit of an enzyme? (1.) The substrate can be altered so it is induced to fit into the enzyme's active site. (2.) The enzyme is altered so it is induced to fit many different types of substrate. (3.) Several sites on an enzyme can be induced to act on a substrate. (4.) The enzyme changes its shape slightly as it binds to the substrate. (5.) All of the above are correct statements about the induced fit. 58. A competitive inhibitor competes with the __________ at the __________ of an enzyme. (1.) product ... active site (2.) product ... allosteric site (3.) substrate ... active site (4.) substrate ... allosteric site (5.) substrate ... active site and allosteric site 59. Water is a polar molecule. This means that (1.) the opposite ends of the molecule have opposite charges (2.) water molecules are linear, like a pole (3.) water is one of the many hydrophobic molecules (4.) the atoms in water have equal electronegativities (5.) all of the above 60. Water resists temperature change because (1.) large bodies of water cannot store heat (2.) heating water absorbs energy by disrupting the hydrogen bonds before evaporation can occur (3.) evaporation of water heats the surface it leaves (4.) hydrogen bonding increases water's ability to vaporize (5.) none of the above 61. That coastal climates are more moderate than inland climates is due primarily to water's high (1.) heat of fusion (2.) surface tension (3.) density (4.) heat of vaporization (5.) specific heat 62. The fatty acid tail of a phospholipid is ___________ because it ___________. (1.) hydrophobic ... dissolves easily in water (2.) hydrophobic ... has no charges to which water molecules can adhere (3.) hydrophilic ... consists of units assembled by dehydration synthesis (4.) hydrophilic ... is easily hydrolyzed into its monomers (5.) hydrophobic ... consists of units assembled by dehydration synthesis 63. The overall three-dimensional shape of a polypeptide is called the (1.) double helix (2.) primary structure (3.) secondary structure (4.) tertiary structure (5.) quaternary structure 64. If an intestinal cell in a chimpanzee contains 48 chromosomes, how many chromosomes would a chimpanzee sperm cell would contain? (1.) 3 (2.) 6 (3.) 12 (4.) 24 (5.) 48 65. The region of a chromosome holding the two double strands of replicated DNA together is called (1.) chromatin (2.) a centriole (3.) a centromere (4.) a chromatid (5.) an aster 66. DNA replication occurs in (1.) prophase of both mitosis and meiosis (2.) metaphase of meiosis only (3.) the S phase of interphase in both somatic and reproductive cells (4.) the G1 phase of interphase in reproductive cells only (5.) the cytokinesis portion of the cell's life cycle 67. Which is NOT a property of water? (1.) Water is an excellent solvent. (2.) Water has a high heat capacity. (3.) Water has a low surface tension. (4.) Water has cohesive properties. (5.) As water freezes it becomes less dense than when in its liquid form. 68. An amino acid is characterized by which of the following functional groups? (1.) amino and hydroxyl (2.) amino and amino (3.) amino and aldehyde (4.) amino and carboxyl (5.) carboxyl and keto 69. At which phase of the cell cycle does DNA replication occur? (1.) G0 (2.) G1 (3.) S (4.) G2 (5.) M (6.) none of the previous 70. In decreasing the activation energy for a given reaction, enzymes (1.) increase the likelihood that molecules involved will collide and form products (2.) decrease the likelihood that molecules involved will collide and form products (3.) have no effect on the rate of product formation in a given reaction (4.) increase the concentration of the substrate (5.) increase the activation energy for a given reaction 71. Mitosis occurs in all the following life cycle events EXCEPT (1.) gamete formation (2.) body cell replacement (3.) development (4.) growth (5.) wound healing 72. When a homozygous recessive organism is crossed with a heterozygous dominant organism, what percentage of the progeny will be heterozygous dominant? (1.) 0% (2.) 25% (3.) 50% (4.) 75% (5.) 100% 73. A reaction is regulated by regulating its enzyme. In competitive inhibition (1.) An enzyme becomes more receptive to additional substrate molecules after one substrate molecule attaches to an active site. (2.) The inhibitor binds to an enzyme at locations other than an active or allosteric site. (3.) An end product of a series of reactions acts as an allosteric inhibitor, shutting down one of the enzymes catalyzing the reaction series. (4.) The inhibitor changes the shape of the enzyme which disables its enzymatic activity. (5.) A substance that mimics the substrate inhibits an enzyme by occupying the active site. 74. Which is NOT a property of water? (1.) It has a low heat of vaporization. (2.) It expands when it freezes. (3.) It is a useful solvent. (4.) It has cohesive properties. (5.) It resists changes in temperature better than most other substances. 75. The primary value of a specific type of backcross known as the test cross is to (1.) determine whether a trait is really hereditary (2.) permit detection of recessive genes (3.) reveal cases of blending inheritance (4.) reveal remote ancestors (5.) reveal sex linked inheritance 76. A plant that has a stem with scattered vascular bundles, leaves with parallel venation, and seeds with a single cotyledon is probably a (1.) bean plant (2.) moss (3.) pine (4.) corn plant (5.) liverwort 77. In corn, the trait for tall plants (T) is dominant to the trait for dwarf plants (t) and the trait for colored kernels (C) is dominant to the trait for white kernels (c). In a particular cross of corn plants, the probability of the offspring being tall is 1/2 and the probability of a kernel being colored is 3/4. Which of the following most probably represents the parental genotypes? (1.) TtCc X ttCc (2.) TrCc X TtCc (3.) TtCc X ttcc (4.) TTCc X ttCc (5.) TTCc X TtCc 78. A form of vitamin-D resistant rickets, known as hypophosphatemia, is inherited as an X-linked dominant trait. If a male with hypophosphatemia marries a normal female, which prediction concerning their potential progeny would be true? (1.) All the sons would inherit the disease. (2.) All the daughters would inherit the disease. (3.) About 50% of the sons would inherit the disease. (4.) About 50% of the daughters would inherit the disease. (5.) None of the daughters would inherit the disease. 79. The end products of the light-dependent reactions of photosynthesis are (1.) ADP, water, NADPH2 (2.) ADP, PGAL, RuBP (3.) ATP, CO2, water (4.) ATP, NADPH2, O2 (5.) CO2, H+, PGAL 80. The cytoplasmic channels between plant cells which are most similar to gap junctions between animal cells are called (1.) middle lamellas (2.) tonoplasts (3.) plasmodesmata (4.) tight junctions (5.) desmosomes Questions 81-83 refer to the diagram which appears below. 81. Which statement about this system is correct? (1.) It is an important component of glycolysis, which can not function without this system. (2.) It takes place in an organelle which has a double membrane. (3.) It is unique to an animal cell. (4.) It is unique to bacteria. (5.) It functions most efficiently in organisms growing under anaerobic conditions. 82. Which is the most important consequence of the operation of the system? (1.) Coenzymes are reduced. (2.) Carbon dioxide is produced. (3.) The pH of the mitochondrial matrix decreases. (4.) Electron carriers in the mitochondrial membrane are irreversibly oxidized. (5.) An electrochemical (proton) gradient is formed. 83. A system similar to that depicted in this figure can also be found in the (1.) Golgi apparatus (2.) lysosome (3.) rough endoplasmic reticulum (4.) chloroplast (5.) ribosome 84. Which statement concerning leaf anatomy is FALSE? (1.) The cuticle is composed of waxes and prevents water loss. (2.) The stomata allow gas diffusion. (3.) The mesophyll contains chlorophyll. (4.) The palisade layer is adjacent to the lower epidermis. Matching Section: For questions 85-87 choose the number of the term that BEST matches each statement: (1.) Xylem (2.) Epidermis (3.) meristem (4.) Phloem (5.) Cortex -------------------------------------------------------------------------------------------------------------------------------------------------------------------85. These cells are responsible for the transport of food. 86. These cells serve as protection for roots, stems, and leaves. 87. These cells are mitotically active and also produce hormones. 88. The cuticle of plant cells: (1.) supports xylem and phloem tubes (2.) is secreted by the cell wall (3.) is specialized for reproduction (4.) waterproofs the epidermal cells Use the following information to answer questions 89 through 91 . A blood cell is placed in pure distilled water solution. 89. The blood cell would probably (1.) expand and burst open (2.) Shrivel up (3.) retain its normal shape (4.) lose its salt content 90. The concentration of water in this example is (1.) greater inside the cell than outside (2.) greater in the immediate environment than in the cell (3.) equal inside and outside the cell (4.) not important to the size of the cell 91. In this example, the environment is _____to the cell. (1.) hypertonic (2.) hypotonic (3.) isotonic 92. The structure that pulls chromatids toward opposite poles is called the (1.) centrosome (2.) spindle (3.) kinetochore (4.) equatorial plate 93. Chromosomes in human skin are (1.) haploid in number (2.) diploid in number (3.) occur as homologous pairs during meiosis (4.) all the previous choices are correct depending upon whether mitosis or mitosis is occurring in these cells 94. The stage in mitosis when the chromosomes line up down the middle is (1.) interphase (2.) prophase (3.) metaphase (4.) anaphase (5.) telophase 95. The main purpose of mitosis is to get daughter cells that (1.) are identical to the parent cell (2.) have half the number of chromosomes as the parent cell (3.) get genetic diversity (4.) are able to adapt Matching Section: For questions 96 through 100, choose the choice from the list below which best describes each statement. (1.) chloroplast (2.) cytosol (3) cell membrane (4.) ribosome (5.) mitochondria -------------------------------------------------------------------------------------------------------------------------------------------------------96. Site of protein synthesis 97. 98. 99. 100. liquid part of the cell where an energy conversion from glucose sugar occurs where photosynthesis occurs allows material in and out of the cell 101. The following functions of the smooth ER are correct EXCEPT: (1.) Ca++storage for muscle contraction (2.) adds hydroxyl group to chemicals to speed their removal from the body (3.) involved in protein synthesis (4.) detoxifies poisons (5.) functions in carbohydrate metabolism Matching Question: Use the choices listed below to assist you in answering questions 102-105 which follow. (1.) centriole (2.) lysosome (3.) nucleolus (4.) peroxisome (5.) ribosome ----------------------------------------------------------------------------------------------------------------------------- ----------------------------------102. Found in both prokaryotic and eukaryotic cells. 103. Possesses a microtubule structure similar in form to a basal body. 104. Assembles ribosomal precursors. 105. Contains hydrolytic enzymes associated with the intracellular digestion of macromolecules. 106. To overcome an energy barrier between reactants and products, energy must be provided to get the reaction started. This energy, which is recovered as the reaction proceeds, is called: (1.) activation energy (2.) initiation energy (3.) reaction energy (4.) kinetic energy (5.) potential energy 107. Identical twins were born with genes for a genetic disorder that can be controlled by diet. Both twins were placed on this diet, which excludes a certain amino acid. However, one twin chose not to follow the diet and developed the genetic disorder. The other twin followed the diet and did not develop the disorder. This difference between the twins illustrates that (1.) gene expression is not influenced by biochemical factors (2.) gene expression is influenced by the environment (3.) identical twins do not always have the same genotype (4.) the genetic disorder is inherited by identical twins, only 108. In the presence of alcohol dehydrogenase, the rate of reduction of acetaldehyde to ethanol increases as you increase the concentration of acetaldehyde. Eventually the rate of the reaction reaches a maximum, where further increases in the concentration of acetaldehyde have no effect. Why? (1.) all of the alcohol dehydrogenase molecules are bound to acetaldehyde molecules (2.) at high concentrations of acetaldehyde, the activation energy of the reaction decreases (3.) the enzyme is no longer specific for acetaldehyde (4.) at high concentrations of acetaldehyde, the change in free energy of the reaction decreases 109. In humans, the gene for red hair and the gene for freckles are often inherited together because both genes are located on the same chromosome. This observation best illustrates the concept of (1.) gene linkage (2.) dominance (3.) independent assortment (4.) hybridization Note that question 110 has only three choices. 110. Which statement best describes the relationship between the number of genes and number of chromosomes in human skin cells? (1.) There are more genes than chromosomes in skin cells. (2.) There are more chromosomes than genes in skin cells. (3.) There are an equal number of chromosomes and genes in skin cells. 111. A woman has a gene that causes a visual disorder. To prevent the gene from appearing in future generations, the defective gene would have to be repaired in the mother's (1.) eye (2.) uterus (3.) nervous system (4.) reproductive cells 112. How many times as efficient is aerobic respiration compared to anaerobic respiration? (1.) 2X (2.) 10X (3.) 18X (4.) 36X 113. The greatest amount of energy is released by the (1.) oxidation of glucose to lactic acid (2.) conversion of carbon dioxide and water to glucose (3.) conversion of glucose to pyruvic acid (4.) oxidation of glucose to carbon dioxide and water 114. The complete hydrolysis of carbohydrates usually results in the production of (1.) carbon dioxide (2.) simple sugars (3.) glycogen (4.) urea 115. Which substances are commonly used as the building blocks in the synthesis of some proteins? (1.) sugars (2.) amino acids (3.) fatty acids and glycerol (4.) amino acids and glycerols 116. Which group of organic compounds includes the enzymes? (1.) proteins (2.) starches (3.) carbohydrates (4.) lipids 117. A hydrolysis reaction occurs when (1.) two simpler molecules are combined and water is split out in the reaction (2.) a complex molecule is split into simpler molecules by the addition of water (3.) one element is exchanged for another in a compound (4.) fats are formed from smaller organic molecules 118. In what part of the cell does glycolysis take place? (1.) Cytosol (2.) Mitochondria (3.) Golgi apparatus (4.) ER 119. How many molecules of ATP are produced during glycolysis (the net gain of ATP molecules)? (1.) 1 (2.) 2 (3.) 12 (4.) 24 120. Which phrase best matches the definition of the term hydrophobic? (1.) "water-hating" (2.) "water-loving" (3.) "water-impartial" (4.) "waterstoring" 121. The cytoskeleton is primarily responsible for __________. (1.) Cell shape (2.) Cellular energy (3.) Cellular respiration (4.) Cell density 122. Membrane transport is important for which of the following biological processes? (1.) Protein synthesis (2.) Cell communication (3.) Maintenance of cellular pH (4.) All of the above 123. In which aquatic environment would you expect dissolved oxygen to be highest? (1.) A mountain lake that is clear and cold (2.) A bog where the water is shallow and warm and there is a mat of aquatic plants (3.) A marine tidepool (4.) A cold mountain stream dropping over a series of small rock falls (5.) A coral reef in a still lagoon Use the information below and your knowledge of biology to do question 124. A student wanted to study the effect of nitrogen fertilizer on plant growth, so she took two similar plants and set them on a window sill for a two-week observation period. She watered each plant the same amount, but she gave one a small dose of fertilizer with each watering. She collected data by counting the total number of new leaves on each plant and also measured the height of each plant in centimeters. 124. Which is a significant flaw in this experimental set-up? (1.) There is no variable factor. (2.) There is no control. (3.) There is no repetition. (4.) Measurable results cannot be expected. (5.) It will require too many days of data collection. 125. What is the role of KOH in our cell respiration experiment? (1.) It serves as an electron donor to promote cellular respiration. (2.) As KOH breaks down, the oxygen needed for cellular respiration is released. (3.) It serves as a temporary energy source for the respiring organism. (4.) It binds with carbon dioxide to form a solid, preventing CO2 production from affecting gas volume. (5.) Its attraction for water will cause water to enter the respirometer. 126. Which statement is correct? (1.) Crossing over occurs in prophase I of meiosis and metaphase of mitosis. (2.) DNA replication occurs once prior to mitosis and twice prior to meiosis. (3.) Both mitosis and meiosis result in daughter cells identical to the parent cells. (4.) Karyokinesis occurs once in mitosis and twice in meiosis. (5.) Synapsis occurs in prophase of mitosis. 127. The cell cycle in a certain cell type has a duration of 16 hours. The nuclei of 660 cells showed 26 cells in anaphase. What is the approximate duration of anaphase in these cells? (1.) 2 minutes (2.) 13 minutes (3.) 19 minutes (4.) 38 minutes (5.) 647 minutes The following are results from an experiment involving a fungus and crossing over. Number of Asci Counted in Sordaria/ Spore Arrangement 7 8 3 4 1 2 4 4 2 2 2 2 light/4 dark/4 light/2 dark/2 dark/4 light/4 dark spores light spores dark/2 light/2 dark spores light/2 dark/2 light spores light/2 dark spores dark/2 light spores 128. How many of these asci contain a spore arrangement that resulted from crossing over? (1.) 3 (2.) 7 (3.) 8 (4.) 10 (5.) 15 129. Which statement describes the currently accepted theory of how an enzyme and its substrate fit together? (1.) As the product is released, the enzyme breaks down. (2.) The enzyme is like a key that fits into the substrate, which is like a lock. (3.) The active site is permanently changed by its interaction with the substrate. (4.) As the substrate binds to the enzyme, the shape of the enzyme site changes to accommodate the reaction. 130. In noncompetitive inhibition, the allosteric inhibitor (1.) attaches to the active site, preventing the substrate from attaching there. (2.) attaches to the substrate, preventing it from attaching to the active site. (3.) changes the pH of the environment, thus preventing enzyme-substrate complex formation. (4.) causes the substrates to polymerize, preventing individual enzymesubstrate attachment. (5.) attaches to the enzyme at a site away from the active site, altering the shape of the enzyme. 131. In competitive inhibition, the allosteric inhibitor (1.) attaches to the active site, preventing the substrate from attaching there. (2.) attaches to the substrate, preventing it from attaching to the active site. (3.) changes the pH of the environment, thus preventing enzyme-substrate complex formation. (4.) causes the substrates to polymerize, preventing individual enzymesubstrate attachment. (5.) attaches to the enzyme at a site away from the active site, altering the shape of the enzyme. 132. Which is most similar to the process of competitive inhibition? (1.) When you are about to park your car in your spot, a bulldozer comes along and smashes your car away from the spot. (2.) When you arrive at work in the morning, you are unable to park your car in your assigned parking spot because someone has placed a giant cement block in front of your spot. (3.) When you arrive at work in the morning, you are unable to park your car in your assigned parking spot because the car of the person next to you has taken up just enough space that you can not fit your own car in. (4) When you arrive at work in the morning, you are unable to park your car in your parking spot, because someone with a car exactly like yours has already taken your spot, leaving you nowhere to park your car. Base your answers to questions 133 and 134 below on the reading passage that follows and your knowledge in biology. A student ground 1 gram of fresh liver in a mortar, placed the ground liver in a test tube, and added 1 ml of peroxide. The gas that was generated was collected. A glowing splint burst into flames when placed in the gas. The student then repeated the procedure, using one gram of boiled liver and one gram of liver treated with a strong acid. When peroxide was added to each sample of liver, no gas was generated. 133. The gas that was generated was most likely (1.) oxygen (2.) nitrogen (3.) carbon dioxide (4.) hydrogen (5.) ammonia (6.) water vapor 134. If the substance in the liver that acted on the peroxide was an enzyme, it could (1.) be recovered from the living tissue that had not been boiled or treated with acid after the reaction ceased (2.) not be recovered because it was consumed while engaging in its catalytic reaction activities (3.) not be recovered because there is no enzyme in liver that catalyzes the breakdown of peroxide (4.) not be recovered because grinding would break up the molecule (5.) be recovered only before the peroxide was added 135. Which one of the following has a carboxyl group? (1.) R–NH2 (2.) R–SH (3.) R–OH (4.) R-COOH 136. Which one of the following is a weak acid? (1.) R–PO4 R–OH (4.) R-COOH (2.) R–SH (3.) 137. Which one of the following has an amino group? (1.) R–NH2 (2.) R–SH (3.) R-COOH (4.) R–OH 138. Which one of the following has a sulfhydryl group? (1.) R–NH2 (2.) R–SH (3.) R-COOH (4.) R–OH 139. Some substances, such as oil and gasoline, will not dissolve in water because (1.) their molecules are so large (2.) their molecules have no charges or partial charges to which water molecules can adhere (3.) they do not ionize (4.) their electrons are so stable that they do not exchange with water molecules (5.) oil and gasoline are inorganic compounds 140. From your knowledge of organic chemistry, you would predict that an abscisic acid (ABA) molecule has a(n) __________ group. (1.) carboxyl (2.) hydroxyl (3.) carbonyl (4.) amino (5.) sulfhydryl 141. The majority of ATP molecules derived from nutrient metabolism are generated by (the): (1.) anaerobic fermentation and glycolysis (2.) fermentation and electron transport chain (3.) glycolysis and substrate phosphorylation (4.) Krebs cycle and electron transport chain (5.) substrate phosphorylation 142. What is the molecule illustrated above? (1.) a polyunsaturated triglyceride (2.) an unsaturated fatty acid (3.) likely to be a common component of plant proteins (4.) saturated fatty acid (5.) similar in structure to a steroid 143. Which process would include a net movement of sugar molecules through a membrane from a region of higher concentration to a region of lower concentration? (1.) osmosis (2.) cyclosis (3.) passive transport (4.) active transport 144. In the human body, the potassium ion can pass easily through cell membranes, yet the potassium ion concentration is higher inside many cells than it is outside these cells. This condition is mainly a result of the process of (1.) passive transport (2.) active transport (3.) osmosis (4.) pinocytosis 145.The primary function of root hairs in a plant is to (1.) prevent excessive loss of water (2.) provide increased surface area for absorption (3.) conduct water and minerals upward (4.) conduct organic food materials upward and downward 146. Which compounds are produced in human muscle cells as a result of the oxidation of glucose in the absence of oxygen? (1.) lipase and water (2.) sucrase and carbon dioxide (3.) ethyl alcohol and ATP (4.) lactic acid and ATP 147. Most animals make energy available for cell activity by transferring the potential energy of glucose to ATP. This process occurs during (1.) aerobic respiration, only (2.) anaerobic respiration, only (3.) both aerobic and anaerobic respiration (4.) neither aerobic nor anaerobic respiration 148. The largest number of cells in a group of onion root tip cells would be found in (1.) the M stage (2.) Interphase (3.) G1 (4.) the S stage (5.) metaphase (6.) in G7 149. Alcohol fermentation and aerobic respiration are similar in that both processes (1.) utilize light (2.) produce ethyl alcohol (3.) require free oxygen (4.) release carbon dioxide 150. The net flow of materials through the membrane of a cell against a concentration gradient is known as (1.) passive transport (2.) active transport (3.) osmosis (4.) pinocytosis Do the following essays. 1. Membranes are important structural features of cells. (a.) Describe how membrane structure is related to the transport of materials across a membrane. (b.) Describe the role of membranes in the synthesis of ATP in respiration. 2. Describe the essential features of an experimental apparatus that could be used to measure oxygen consumption by a small organism. List at least four of these features of the apparatus (not including the organism). Explain why each of these features is necessary. 3. Enzymes are biological catalysts. (a.) Relate the chemical structure of an enzyme to its specificity. (b.) Design a quantitative experiment to investigate the influence of pH on enzyme activity. Include a problem, hypothesis, and procedure. 4. List 5 properties of water associated with hydrogen bonding and explain why these properties are essential to living things. 5. (a.) Explain the processes resulting in genetic variability in an organism due to meiotic cell division. Use the terms synapsis, tetrad, crossing over, and variability correctly in your explanation. (b.) Explain how the meiotic process discussed above drive the process of natural selection. 6. How can carbohydrate, neutral lipids, and proteins usually be distinguished based on their molecular formulae? 7. An AP Biology student prepared solutions of 0.8 M, 0.6 M, 0.4 M, and 0.2 M sucrose, but forgot to label them. After realizing the error, the student randomly labeled the flasks containing these four unknown solutions as flask A, flask B, flask C, and flask D. Design an experiment, based on the principles of diffusion and osmosis, that the assistant could use to determine which of the flasks contains each of the four unknown solutions. Include in your answer: (a) a description of how you would set up and perform the experiment (b) the results you would expect from your experiment (c) an explanation of those results based on the principles involved. (include terms like direction of osmosis as well as terms which describe relative concentration in this explanation) 8. Some researchers have proposed that doing 50 jumping jacks prior to squeezing a clothespin will increase the rate that that individual can squeeze a clothespin in one minute. Other researchers dispute this claim. a.) Using the correct format for stating a hypothesis, correctly state a hypothesis for this experiment. b.) What is the independent variable in this experiment? c.) What is the dependent variable in this experiment? d.) What is the control in this experiment? 9. Explain how the addition of the following influences the rate of most enzyme controlled reactions in living systems and explain HOW and WHY. a.) b.) c.) d.) e.) increase in temperature over 50 C adding concentrated sulfuric acid adding more substrate to a fixed amount of enzyme the addition of a competititive inhibitor the addition of a noncompetitive inhibitor 10. (a.) List two advantages C-4 metabolism appears to have over C-3 photosynthesis metabolism in plants. (b.) List an advantage and a disadvantage of CAM metabolism in those plants utilizing this method. 11. The cell is a unit of biological activity that is delimited by a semipermeable membrane and is capable of self-reproduction in a medium free from other living systems. "Plastids and mitochondria were originally free-living prokaryotes that early in evolution that took up residence inside eukaryotic cells." (a.) Describe the structure of both the chloroplast and mitochondrion. State the function of each in the cell with particular reference to what goes on where. (b.) Describe the evidence that supports the quote above. 12. Identify all the numbered structures on the cross section of the plant leaf below and state their functions. http://www.ekcsk12.org/science/apbio/practicemidterm2005-2006.html Multiple Choice/Matching Section 1. 2. 3. 4. 5. 6. 7. 8. 4 4 3 4 2 2 5 2 9. 3 10. 11. 78. 79. 80. 81. 82. 83. 84. 2 3 5 4 3 2 5 4 4 12. 1 13. 3 14. 1 15. 4 16. 4 17. 1 18. 4 19. 3 20. 1 (although ribosomes on their surface do # 5) 21. 5 22. 3 89. 1 100. 3 90. 2 101. 3 91. 2 102. 5 92. 2 103. 1 93. 2 104. 3 94. 3 105. 2 95. 1 106. 1 23. 24. 25. 26. 27. 28. 29. 30. 5 3 3 2 1 2 6 2 31. 5 32. 5 (or conceivably 1) 33. 5 111. 4 122. 4 112. 4 123. 4 113. 4 124. 3 114. 2 125. 4 115. 2 126. 4 116. 1 127. 4 117. 2 128. 4 34. 35. 36. 37. 38. 39. 40. 41. 2 5 4 5 2 3 1 4 45. 46. 47. 48. 49. 50. 51. 52. 1 1 2 1 2 3 1 1 56. 57. 58. 59. 60. 61. 62. 63. 3 4 3 1 2 5 2 4 67. 68. 69. 70. 71. 72. 73. 74. 3 4 3 1 1 3 5 1 42. 4 53. 2 64. 4 75. 2 43. 44. 133. 134. 135. 136. 137. 138. 139. 1 54. 3 65. 3 76. 4 2 55. 2 66. 3 77. 1 1 144. 2 1 145. 2 4 146. 4 4 147. 3 1 148. 2 2 149. 4 2 150. 2 85. 86. 87. 88. 4 2 3 5 96. 4 97. 2 98. 5 99. 1 107. 108. 109. 110. 2 1 1 1 118. 1 119. 2 120. 1 121. 1 129. 130. 131. 132. 4 5 1 4 140. 141. 142. 143. 1 4 2 3 1. (a.) Membrane Structural features: Phospholipid structure - hydrophilic end with phosphate with a pair of hydrophobic hydrocarbon tails -- contains two phospholipid bilayers -- is fluid mosaic description with proteins embedded in the membrane used for transport -- sterols are also embedded in the membrane Welllabeled diagram with description of functions may replace this description. Membrane function: Use the term "selectively permeable" or a good definition of selective permeability or an explanation of the role of phospholipids or proteins including pore proteins in determining selective permeability. Essay must include a description of the effect of size, charge, etc.on membrane permeability. Passive transport or diffusion / osmosis must be related to the concentration gradient on both sides of the membrane. Ion transport may be mentioned in reference to channel: transport as a mechanism for a change in permeability. At least one other terms which must be defined for full credit include facilitated diffusion, active transport, exocytosis, endocytosis, phagocytosis, and pinocytosis. (b.) Role of the Membrane in the Production of ATP in Respiration: Chemiosmosis: -- Involved molecules such as electron transport molecules are embedded in the membrane in a sequentially organized manner The energy comes from the flow of electrons to establish a H+ / Proton / pH gradient Movement through the membrane generates ATP A specific protein makes ATP (ATP synthase) through an F-0-F-1 complex 2. Some features of a respirometer (my apology for the crude paintbrush drawing) include: 1 = pipette which measures the oxygen consumption by the organism 2 = stopper and sealant which prevent water and gases from leaking into the respirometer 3 = organism (consuming oxygen and releasing CO2 ... can't be part of the answer) 4 = cotton which separates the caustic KOH from the organism The unlabled line at the bottom is pointing to the KOH which absorbs the CO2 released by the organism so it doesn't cancel out the consumption of oxygen into the pipette and respirometer 3. (a.) The structure of an enzyme influences its catalytic activity. The enzyme has a specific 3-D shape/ or tertiary structure which allows it to fit with a specific substrate. The active site or the enzyme contains a groove or pocket which has a special shape for substrate. This model of enzyme structure and function is called the "lock and key" and model. Some factors such as cofactors, allosteric interactions, or inhibitors change to the enzyme's shape to allow it or in some cases not allow it to fit with the substrate. Many enzymes can slightly change their shape to fit the substrate which is called the induced fit theory. Enzymes speed chemical reactions by lowering the activation energy needed to start the chemical reaction. (b.) Problem: How does pH influence enzyme activity? Hypothesis: Very strong acids or bases prevent enzymes from functioning. [Procedure] -- put 10 ml of an acid of pH 4 in one test tube, 10 ml of distilled water in another test tube, and 10 ml of a base of pH 10 in another test tube -- make certain that conditions such as temperature, size of the test tubes, cleanliness of the test tubes, etc. are the same for all test tubes -- put one ml of an enzyme in each solution -- observe the rate of chemical reaction (bubbling, color change, etc. in each test tube and record (control -- water solution, independent variable -- solution pH, dependent variable -- reaction activity) 4. Some possible answers: polarity -- unequal charge distribution -- causes hydrogen bonding adhesion -- caused by unequal charges -- attraction for unlike substance cohesion -- attraction between water molecules -- due to hydrogen bonding -- produces surface thension of water striders walking capillary action -- water rises in tubes of narrow diameter leading to transpiration high specific heat -- allows water to change temp slowly and moderate climate high boiling point -- organisms don’t boil away -- good evaporative coolant imbibition --- water soaks into other substances due to its hydrogen bonding -- such as seeds -- Most dense at 4 C (ice floats and results in thermal overturn mixing oxygen and nutrients in water) Water is a stable compound -- used in metabolic reactions Water is a good conductor when electrolytes are mixed in it (electric eel ,etc.) Water is not compressible --- results in blood pressure, etc 5.. The meeting of two pair of homologous chromosomes in prophase I of meiosis I is called synapsis. The two pair of homologous chromosomes are called a tetrad. These chromosomes wrap around each other and exchange pieces in a process called crossing over. This means the new chromosome combinations formed in the gametes formed in meiosis will be different from the original chromosome combinations. This variation in the chromosomes means that the offspring formed in sexual reproduction will exhibit variations. These variations may produce organisms which are better able to better survive a change in the environment. This process is called survival of the fittest. The entire process where a variation of a species survives and adapts while another does not and is removed from the population is called natural selection. 6. Both neutral lipids and carbohydrates have carbon, hydrogen, and oxygen in their structure. In carbohydrates the ratio of hydrogen to oxygen is 2:1, while it is in excess of this in a neutral lipid. Proteins have in addition to the previous three elements nitrogen in their structure. 7. (a) a description of how you would set up and perform the experiment Set up must include: all four solutions (1) a way of comparing them and what they will do (either a standard dialysis bag or solution outside varying bags) (1) a set up which clearly implies the student is testing an osmotic situation (b) the results you would expect from your experiment -- to get credit the student must show that the greater the difference in concentration from the dialysis bag, the greater the rate of osmosis (c) an explanation of those results based on the principles involved. (include terms like direction of osmosis as well as terms which describe relative concentration in this explanation) -- direction of osmosis clearly implied -- hypertonic (or greater concentration of solute/or lesser solvent) -- hypotonic (or lesser concentration of solute/or greater solvent) 8. (a.) If I exercise by doing jumping jacks prior to squeezing the clothespin, then the rate of clothespin squeezing will increase. (Note that the hypothesis is properly stated as an if .. then statement relating the independent and dependent variables together.) (b.) Exercising before squeezing the clothespin is the independent variable. (c.) The dependent variable is the number of clothespin squeezes in one minute. (d.) The control in this experiment is clothespin squeezing without exercising before hand. 9. (a.) An increase in temperature over 50 C will slow or stop reaction rate because it denatures the enzyme. (b.) Adding concentrated sulfuric acid will markedly slow the reaction rate, because its ionic interactions will denature the enzyme (c.) Adding more substrate to a fixed amount of enzyme will increase the reaction rate until all the enzyme molecules are combined with all the substrate molecules, then the reaction rate will level off, as adding more substrate molecules can have no additional effect, as there are no enzyme molecules to combine with. (d.) The addition of a competititive inhibitor will occupy the active site of the enzyme, thus slowing the reaction rate of the enzyme. (e.) The addition of a noncompetitive inhibitor to a site away from the active site (allosteric site) will change the overall shape of the enzyme molecule, including the active site, so the enzyme does not function. 10. (a.) C-4 plants are able to maximize photorespiration by using intense sunlight more efficiently to enhance sugar production. (b.) Plants engaging in CAM metabolism are able to fix all the carbon dioxide they use in the form of organic acids at night. This allows these plants to close their stomata during the day to conserve water. A disadvantage is that by only opening their stomata at night, these plants have a slower rate of photosynthesis that either C-3 or C-4 plants. 11. (a.) Both the chloroplast and mitochondrion contain an inner membrane in addition to their outer membrane. The inner membrane of the chloroplast or thylakoid is where the major events of the light dependent reactions of photosynthesis occur. The dark reactions of photosynthesis occur outside the thylakoids in the stroma fluid of the outer compartment. The inner membrane of the mitochondrion is called the cristae. The major events involving the electron transport chain and the chemiosmotic synthesis of ATP occur here in the process of cellular respiration. (The actual synthesis of ATP in this process occurs in the mitochondrial matrix.) (b.) Both the mitochondria and chloroplasts contain their own DNA which is independent of the DNA in the nuclei of the cells they are found in. This circular DNA is very similar to that found in bacteria. The concept of serial endosymbiosis states that mitochondria and chloroplasts were small endosymbionts living in a larger cell that were eventually taken over by that cell. Chloroplasts and mitochondria can replicate independently in cells to this day by a process similar to binary fission in bacteria. Ribosomal RNA in chloroplasts and mitochondria are similar to that of bacteria as well. 1 = cuticle -waterproofs and protects leaf 2 = upper epidermis -water proofs and protects leaf 3 = palisade mesophyll -where most photosynthesis occurs in dicot leaves 4 = spongy mesophyll -does most gas exchange and responsible for some photosynthesis 5 = vein (or vascular bundle) -contains the conducting tissue within the leaf (xylem and phloem) 6 = lower epidermis -waterproofs and protects leaf 7 = guard cell -- opens and closes stomate 8 = stomate -responsible for regulating gas exchange and water loss (transpiration) from the leaf http://www.ekcsk12.org/science/apbio/practicemidterm2005-2006answers.html