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  • 1. 
    What is the final result of mitosis?
    • A. 

      Genetically identical 2n somatic cells

    • B. 

      Genetically different 2n somatic cells

    • C. 

      Genetically identical 1n somatic cells

    • D. 

      Genetically identical 2n gamete cells


  • 2. 
    The first gap in the cell cycle (G1) corresponds to __________.
    • A. 

      Normal growth and cell function

    • B. 

      The phase in which DNA is being replicated

    • C. 

      The beginning of mitosis

    • D. 

      The phase between DNA replication and the M phase


  • 3. 
    The microtubule-organizing center found in animal cells is an identifiable structure present during all phases of the cell cycle.  Specifically, it is known as which of the following?
    • A. 

      Microtubulin

    • B. 

      Centrosome

    • C. 

      Centromere

    • D. 

      Kinetochore


  • 4. 
    Nerve cells lose their ability to undergo mitosis.  Instead, they are permanently stuck in _______.
    • A. 

      G0

    • B. 

      G2

    • C. 

      S of interphase

    • D. 

      Metaphase


  • 5. 
    What would happen if MPF (mitosis-promoting factor) is introduced into immature frog oocytes that are arrested in G2?
    • A. 

      Nothing happens

    • B. 

      The cells undergo meiosis

    • C. 

      The cells enter mitosis

    • D. 

      Cell differentiation is triggered.


  • 6. 
    Once a cell completes mitosis, molecular division triggers must be turned off.  What happens to MPF during mitosis?
    • A. 

      It is completely degraded

    • B. 

      It is exported from the cell

    • C. 

      Cyclin is degraded; the concentration of cyclin-dependant kinase remains unchanged but without cyclin MPF is not formed

    • D. 

      Cyclin-dependant kinase is degraded; cyclin concentration remains constant but without cyclin-dependant kinase, MPF is not formed.


  • 7. 
    In human and many other eukaryotic species' cells, the nuclear membrane has to disappear in order for what to take place?
    • A. 

      Cytokinesis

    • B. 

      Attachment of mitotic spindle to kinetochores

    • C. 

      Splitting of the centrosomes

    • D. 

      The cell plate to form


  • 8. 
    The mitotic spindle is a microtubular structure that is involved in ________.
    • A. 

      Splitting of the cell (cytokinesis) following mitosis

    • B. 

      Triggering the compaction and condensation of chromasomes

    • C. 

      Dissolving the nuclear membrane

    • D. 

      Separation of sister chromatids


  • 9. 
    Metaphase is characterized by _________.
    • A. 

      Aligning of chromasomes on the equator of the cell

    • B. 

      Splitting of the centromeres

    • C. 

      Cytokinesis

    • D. 

      Separation of sister chromatids


  • 10. 
    After chromasome separation in cell division, cytoplasm is divided between the two daughter cells in a process known as _______.
    • A. 

      Cloning

    • B. 

      Cytokinesis

    • C. 

      Binary fission

    • D. 

      G1 phase


  • 11. 
    Once researchers understood that chromasomes are moved by the spindle microtubules, the next question they wanted to answer is how the microtubules function to bring about this process.  They used fluorescent labels to make the chromasomes and the microtubular structures fluoresce.  When anaphase begain (centromeres split), they photobleached a section of microtubules.  As chromasomes moved toward the poles of the daughter cells, the photobleached sections of the microtubules remained stationary.  This result suggests that _______.
    • A. 

      The microtubules elongate and shorten at the centrosome end

    • B. 

      The microtubules overlap, and slide with respect to one another, effectively shortening the microtubules without depolymerizing the actual fiber.

    • C. 

      The microtubules elongate and shorten at their kinetochore end

    • D. 

      The microtubules are of constant length; centrosomes move father apart to separate chromasomes.


  • 12. 
    Which of the following processes contributes directly to genetic variation?
    • A. 

      Binary fission

    • B. 

      Mitosis

    • C. 

      Meiosis

    • D. 

      DNA replication


  • 13. 
    Somatic cells of roundworms have four chromasomes  How many chromasomes would you find in an ovum (egg) from a roundworm?
    • A. 

      Four

    • B. 

      Two

    • C. 

      Eight

    • D. 

      A diploid number


  • 14. 
    Homologous chromasomes are separated during ________.
    • A. 

      Anaphase II

    • B. 

      Prophase I

    • C. 

      Mitosis

    • D. 

      Anaphase I


  • 15. 
    Chromasomes and their homologues align at the equator of the cell during ________.
    • A. 

      Telophase I

    • B. 

      Metaphase I

    • C. 

      Telophase II

    • D. 

      Metaphase II


  • 16. 
    In meiosis, centromeres split and sister chromasomes migrate to opposite poles in ________.
    • A. 

      Anaphase I

    • B. 

      Telophase I

    • C. 

      Anaphase II

    • D. 

      Telophase II


  • 17. 
    At what stage of meiosis does DNA replication take place?
    • A. 

      DNA replication does not take place in cells destined to undergo meiosis

    • B. 

      Prophase I

    • C. 

      Between meiosis I and meiosis II

    • D. 

      None. DNA replication occurs before meiosis I begins.


  • 18. 
    What is a major difference between meiosis II and mitosis?
    • A. 

      Homologues align on the metaphase plate in meiosis II

    • B. 

      Sister chromatids separate in mitosis, and homologues separate in meiosis II

    • C. 

      Meiosis II takes place in a haploid cell, while mitosis takes place in diploid cells.

    • D. 

      Crossover takes place in meiosis II.


  • 19. 
    Crossover, the exchange of segments of homologous chromasomes, takes place during which of the following processes?
    • A. 

      Prophase II

    • B. 

      Metaphase I

    • C. 

      Anaphase I

    • D. 

      Synapsis


  • 20. 
    Homologous chromasomes ________.
    • A. 

      Are identical

    • B. 

      Carry information for the same traits

    • C. 

      Carry the same alleles

    • D. 

      Align on the metaphase plate in meiosis II


  • 21. 
    The failure of homologous chromasomes or double stranded chromasomes to separate during meiosis is called:
    • A. 

      Nondisjunction

    • B. 

      Chromosomal aberration

    • C. 

      Missense mutation

    • D. 

      Chromosomal adhesion


  • 22. 
    For the duration of meiosis I, each chromosome is _______.
    • A. 

      In the form of a tetrad

    • B. 

      Two sister chromatids joined by a centromere

    • C. 

      A chromosome and its homologue

    • D. 

      Undergoing synapsis


  • 23. 
    Which of these represents a heterozygous genotype?
    • A. 

      AA

    • B. 

      Aa

    • C. 

      Bb

    • D. 

      Both AA and aa


  • 24. 
    The allele which is traditionally indicated by an uppercase letter is the:
    • A. 

      Dominant allele

    • B. 

      Recessive allele


  • 25. 
    The term 'allele' most accurately refers to:
    • A. 

      Homologous chromasomes

    • B. 

      Dominant genes

    • C. 

      Recessive genes

    • D. 

      Different forms or variations of a gene influencing a trait


  • 26. 
    A father has type AB blood.  Which of the following statements is NOT true?
    • A. 

      His red blood cells have both A and B protein markers (antigens) represented on the surface

    • B. 

      His children could not have type O blood

    • C. 

      His phenotype for blood type is an example of codominance

    • D. 

      He produced antibodies for both A and B blood


  • 27. 
    The device used in genetics to calculate the genotype and phenotype probabilities for offspring of two particular genotype parents is called
    • A. 

      Rubics cube

    • B. 

      Gene matrix

    • C. 

      Pedigree analysis

    • D. 

      Punnett square


  • 28. 
    Traits controlled by alleles on the sex chromasome (X or Y) are said to be:
    • A. 

      Sex-linked

    • B. 

      Autosomal

    • C. 

      Codominant

    • D. 

      Multiple alleles


  • 29. 
    Word descriptions of a trait such as "brown", "wavy-haired", "round", "wrinkled", or "green" represent:
    • A. 

      Phenotype only

    • B. 

      Genotype only

    • C. 

      Both phenotype and genotype

    • D. 

      Neither phenotype nor genotype


  • 30. 
    Free earlobes are dominant over attached earlobes.  If two people with attached earlobes have a child, what are the probabilities for the phenotype of their offspring for this trait?
    • A. 

      100% free earlobes

    • B. 

      100% attached earlobes

    • C. 

      50/50 free to attached earlobes

    • D. 

      75% free, 25% attached


  • 31. 
    What scientist first conduced the experiments that led to the discovery of the mechanisms of inheritance?
    • A. 

      Gregor Mendel

    • B. 

      Alfred Russell Wallace

    • C. 

      Georges Cuvier

    • D. 

      Charles Darwin

    • E. 

      Jean-Baptiste Lamarck


  • 32. 
    When a heterozygote has an intermediate phenotype between that of either homozygote, it is called:
    • A. 

      Sex-linked

    • B. 

      Incomplete dominance

    • C. 

      Multifactorial inheritance

    • D. 

      Multiple alleles


  • 33. 
    Color blindness is an X-linked recessive genetic disorder. A father is color blind.  The mother has a homozygous genotype for normal vision.  Choose the correct result regarding children of these parents.
    • A. 

      All male children will be colorblind

    • B. 

      All female children will be colorblind

    • C. 

      All male children will have normal vision

    • D. 

      Both answers A & B are correct

    • E. 

      Both answers B & C are correct


  • 34. 
    A man who carries an allele of an X-linked gene will pass it on to ________.
    • A. 

      All of his daughters

    • B. 

      Half of his daughters

    • C. 

      All of his sons

    • D. 

      Half of his sons

    • E. 

      All of his children


  • 35. 
    Both parents have a heterozygous genotype for a particular trait. What are the chances that an offspring will display the recessive phenotype for that trait?
    • A. 

      75%

    • B. 

      50%

    • C. 

      25%

    • D. 

      Less than 10%

    • E. 

      None of the choices are correct.


  • 36. 
    If a human inherits two X chromasomes (one from each parent), the person will be:
    • A. 

      Female

    • B. 

      Male

    • C. 

      Sterile


  • 37. 
    If an X-linked trait, such as color blindness, is present in a family, the disease will occur more often in male offspring than in female offspring.
    • A. 

      True

    • B. 

      False


  • 38. 
    A man and woman are both of normal pigmentation and have one child out of three who is albino (without pigmentation).  Albinism is an autosomal recessive trait.  What are the genotypes of the albino's parents?
    • A. 

      One parent must be homozygous for the recessive allele; the other parent can be homozygous dominant, homozygous recessive, or heterozygous

    • B. 

      One parent must be heterozygous; the other parent can be homozygous dominant, homozygous recessive, or heterozygous

    • C. 

      Both parents must be heterozygous

    • D. 

      One parent must be homozygous dominant; the other parent must be heterozygous

    • E. 

      Both parents must be homozygous dominant


  • 39. 
    When one trait is governed by two ore more pairs of alleles instead of controlled by only one pair of alleles, this is called:
    • A. 

      A recessive trait

    • B. 

      Polygenic traits

    • C. 

      Codominance

    • D. 

      Incomplete dominance

    • E. 

      Multiple allelism


  • 40. 
    Within a duplicated chromasome, the chromatids are held together by a:
    • A. 

      Centriole

    • B. 

      Centromere

    • C. 

      Chromocenter

    • D. 

      Spindle fiber


  • 41. 
    Prokaryotic organisms lack:
    • A. 

      Replicator molecules (DNA or RNA)

    • B. 

      Cell membranes

    • C. 

      Metabolism

    • D. 

      Organelles

    • E. 

      All of the above


  • 42. 
    How are phospholipid molecules that make up the surface membrane of a cell organized?
    • A. 

      A single-layered structure is formed, with the hydrophobic heads facing in to the interior of the cell and the hydrophobic tails on the outside, facing the exterior environment

    • B. 

      A single-layred structure is formed, with the hydrophobic tails facing in and the hydrophobic tails on the outside

    • C. 

      A two-layered structure is formed, with the hydrophobic tails facing in to each other, sandwiched between the hydrophilic heads that face the interior of the cell and the exterior environment

    • D. 

      A two-layered structure is formed, with the hydrophobic heads facing in to each other, sandwiched between the hydrophilic tails on the outside that face interior of the cell and the exterior environment.

    • E. 

      Both B and D are possible.


  • 43. 
    Which of the following is the outermost feature on the surface of the plant cell?
    • A. 

      Lipid bilayer

    • B. 

      Cholesterol

    • C. 

      Cell wall

    • D. 

      Glycoproteins

    • E. 

      Sugar molecules


  • 44. 
    The primary function of molecular membranes is the transport of ions and molecules in and out of cells--transport is directional and selective.  The moving of molecules from areas of high concetration to that of low concentration is best described as:
    • A. 

      Channel mediated diffusion

    • B. 

      Electron transport

    • C. 

      Active transport

    • D. 

      Inactivated transport

    • E. 

      Passive transport


  • 45. 
    Sugar and CO2 are dissolved in water to make carbonated soft drinks.  Which of the following is the solute?
    • A. 

      The water and the sugar

    • B. 

      The water and the CO2

    • C. 

      The CO2 only

    • D. 

      The sugar and the CO2

    • E. 

      The sugar only


  • 46. 
    A cell's interior is considered isotonic to the surrounding fluid when:
    • A. 

      The solute's concentration is lower within the cell than outside the cell

    • B. 

      The cell's lipid bilayer does not allow any molecules to pass into or out of the cell

    • C. 

      The solute's concentration is higher within the cell than outside the cell

    • D. 

      There is an equal number of water molecules immediately outside the cell as inside the cell

    • E. 

      The solute concentrations are the same within and outside the cell


  • 47. 
    What makes the rough endoplasmic reticulum rough?
    • A. 

      It has a high density of receptor proteins in its membrane

    • B. 

      It is covered with ribosomes

    • C. 

      It is covered with tiny flagella

    • D. 

      Its surface is highly folded to increase surface area

    • E. 

      It is covered with cillia


  • 48. 
    Where are cell membrane components synthesized?
    • A. 

      Endoplasmic reticulum

    • B. 

      Lysosomes

    • C. 

      Golgi apparatus

    • D. 

      Vesicles

    • E. 

      Nucleus


  • 49. 
    The passive transport of water across a membrane from a solution of lower solute concetrate to a solution of higher solute concetration is best described as:
    • A. 

      Active transport

    • B. 

      General diffusion

    • C. 

      Osmosis

    • D. 

      Passive transport

    • E. 

      Facilitated diffusion


  • 50. 
    You are bored at a lunch meeting and surreptitiously place a raisin in your glass of water.  The raisin swells to twice its original size.  Relative to the water, the raisin must have been:
    • A. 

      Hypertonic

    • B. 

      Isotonic

    • C. 

      Hypotonic

    • D. 

      Mesotonic

    • E. 

      Osmotic


  • 51. 
    To absorb large particles, cells engulf them within their plasma membrane in a process called:
    • A. 

      Replication

    • B. 

      Exocytosis

    • C. 

      Endocytosis

    • D. 

      Transcription

    • E. 

      Translation


  • 52. 
    What is the main function of the nucleolus?
    • A. 

      It is the site of ribosome-subunit synthesis

    • B. 

      It produces cell adhesion proteins that are then exported to the cell membrane

    • C. 

      It is the site of photosynthesis in photosynthetic cells

    • D. 

      It produces enzymes that are then exported to the lysosomes

    • E. 

      Its function is not yet known.


  • 53. 
    Which of the following cellular components contains hydrolytic enzymes associated with the digestion of macromolecules?
    • A. 

      Peroxisomes

    • B. 

      Lysosomes

    • C. 

      Centrioles

    • D. 

      Ribosomes


  • 54. 
    In which organelle are lipids synthesized and modified within the eukaryotic cell?
    • A. 

      The Golgi apparatus

    • B. 

      The smooth endoplasmic reticulum

    • C. 

      The lysosomes

    • D. 

      The vesicles

    • E. 

      The rough endoplasmic reticulum


  • 55. 
    Which of the following is an incorrect matching of organelle/cell part with its function?
    • A. 

      Nucleus: contains the DNA for the cell and controls daily function

    • B. 

      Lysosomes: flattened sac of membranes which package and export the proteins and lipids out of the cell

    • C. 

      Ribosomes: the place of protein synthesis

    • D. 

      Vesicles: packages of proteins surrounded by cell membranes that sort the proteins and lipids for packaging

    • E. 

      Mitochondria: produces ATP by breaking down sugar


  • 56. 
    Given that a cell's structure reflects its function, what would you predict that the function ofa cell with a large Golgi apparatus would be?
    • A. 

      Secretion of digestive enzymes

    • B. 

      Storage of lipids

    • C. 

      Movement

    • D. 

      Rapid replication of genetic material and coordination of cell division

    • E. 

      Attachment to bone tissue


  • 57. 
    Peroxisomes:
    • A. 

      Produce lipids and place them in transport vesicles

    • B. 

      Are responsible for detoxifying poisoning substances

    • C. 

      Provide structural support for plant cells and often contain cellulose or lignin

    • D. 

      Are vesicles filled with strong digestive enzymes and acid for breaking down large macromolecules

    • E. 

      Are vesicles filled with specific enzymes for oxidation reactions


  • 58. 
    Which one of the following organelles is NOT found in both plant and animal cells?
    • A. 

      Mitochondrion

    • B. 

      Nucleus

    • C. 

      Smooth endoplasmic reticulum

    • D. 

      Central vacuole


  • 59. 
    Which of the following is NOT a function of the plant vacuole?
    • A. 

      Photosynthesis

    • B. 

      Predator deterrence

    • C. 

      Physical support

    • D. 

      Waste management

    • E. 

      Nutrient storage


  • 60. 
    Which of the following is an important difference between the rough endoplasmic reticulum and the smooth endoplasmic reticulum?
    • A. 

      The rough endoplasmic reticulum is the site of much protein folding and packaging while the smooth endoplasmic reticulum is the site of lipid syntehsis

    • B. 

      The rough endoplasmic reticulum is studded with chloroplasts, while the smooth endoplasmic reticulum is not

    • C. 

      The smooth endoplasmic reticulum is the site of protein synthesis, folding, and packaging, while the rough endoplasmic reticulum is the site of lipid synthesis

    • D. 

      All of the above


  • 61. 
    Which of the following statements represents a major difference between prokaryotic cells and eukaryotic cells?
    • A. 

      Eukaryotic cells are able to carry out photosynthesis, while prokaryotic cells are not able to because they do not have chloroplasts

    • B. 

      Eukaryotic cells tend to have much more extensive inner membrane systems and larger numbers of intracellular organelles than do prokaryotes

    • C. 

      Prokaryotes are not able to carry out aerobic respiration, a process that requires a complex inner-membrane system

    • D. 

      Prokaryotes are generally larger in size than eukaryotes


  • 62. 
    Which one of the following would you fail to find in a prokaryote?
    • A. 

      DNA

    • B. 

      A cell wall

    • C. 

      A mitochondrion

    • D. 

      A plasma membrane


  • 63. 
    Which of the following is NOT a product of photosynthesis?
    • A. 

      Glucose

    • B. 

      Oxygen

    • C. 

      Sugars

    • D. 

      Carbon dioxide

    • E. 

      None of the above; all are products of photosynthesis


  • 64. 
    Carotenoids:
    • A. 

      Are primary pigments in certain plants and algae chloroplasts that fix carbon in place of chlorophyll

    • B. 

      Are the organelles in a leaf cell in which photosynthesis occurs

    • C. 

      Are the stacks of thylakoid membranes in a chloroplast

    • D. 

      Are the organelles in a leaf cell in which respiration occurs

    • E. 

      Are accessory pigments in chloroplasts that protect the chlorophyll by absorbing excessive light energy.


  • 65. 
    A pigment that transmits all wavelengths of visible light appears:
    • A. 

      White

    • B. 

      Green

    • C. 

      Black

    • D. 

      Red

    • E. 

      Violet


  • 66. 
    The most effective portion(s) of the visible spectrum in driving photosynthesis is/are:
    • A. 

      Red, blue, and green portion

    • B. 

      Red and blue portion

    • C. 

      Green portion

    • D. 

      Blue, green, and orange portion

    • E. 

      Yellow, orange, blue, and red portions


  • 67. 
    Biologically speaking, a pigment:
    • A. 

      Is a molecule that absorbs carbon dioxide

    • B. 

      Is a cell that fixes carbon

    • C. 

      Is a molecule that absorbs a photon

    • D. 

      Is a molecule that releases oxygen

    • E. 

      Is a cell that absorbs a photon


  • 68. 
    Which of the following does NOT occur as a direct result of a photon hitting a chlorophyll molecule?
    • A. 

      Excitation of an electron

    • B. 

      Production of ATP

    • C. 

      Reduction/oxidation

    • D. 

      Fluorescence

    • E. 

      A release of heat


  • 69. 
    The light reactions of photosynthesis supply the Calvin cycle with:
    • A. 

      ATP and NADPH

    • B. 

      CO2 and ATP

    • C. 

      Sugar and O2

    • D. 

      Light energy


  • 70. 
    Photosystems:
    • A. 

      Are arrangements of thylakoid membranes within the plant cell wall

    • B. 

      Are arrangements of ATP-synthase molecules within chloroplasts

    • C. 

      Are arrangements of chloroplasts within the cells lining the surface of leaves

    • D. 

      Are the wavelengths of light that reach the earth from the sun

    • E. 

      Are arrangements of light-catching pigments within chloroplasts


  • 71. 
    In photosynthesis, both the first and the second photosystems:
    • A. 

      Generate energy storage molecules

    • B. 

      Generate ADP

    • C. 

      Generate oxygen

    • D. 

      Require CO2


  • 72. 
    Which of the following statements about the light reactions of photosynthesis are correct?
    • A. 

      Pigments absorb light energy, which excites electrons

    • B. 

      The energy of the sun is captured and converted to chemical energy

    • C. 

      Water molecules split, providing a source of electrons

    • D. 

      Only A and C are correct

    • E. 

      A B and C are correct


  • 73. 
    Where does the Calvin cycle take place?
    • A. 

      In the stroma of the chloroplast

    • B. 

      In the thylakoid membrane

    • C. 

      In the Hobbesian membrane

    • D. 

      In the cellular cytoplasm

    • E. 

      Around the chlorophyll molecule


  • 74. 
    The most abundant protein in the world is the enzyme that initiates the fixation of carbon in the Calvin cycle.  This enzyme is called:
    • A. 

      Rubisco

    • B. 

      ATP-synthase

    • C. 

      Glyceraldehyde-3-phosphate (G3P)

    • D. 

      Crassulacean acid


  • 75. 
    Which of the following does NOT occur during the Calvin cycle?
    • A. 

      Consumption of ATP

    • B. 

      Oxidation of NADPH

    • C. 

      Splitting of water

    • D. 

      Consumption of carbon dioxide

    • E. 

      Carbon fixation


  • 76. 
    The final electron acceptor(s) associated with photosystem I is/are ___________.
    • A. 

      Oxygen

    • B. 

      Water

    • C. 

      NADP

    • D. 

      FAD


  • 77. 
    One turn of the Calvin cycle uses _______ molecules of CO2, _______ molecules of NADPH, and __________ molecules of ATP.
    • A. 

      3,6,9

    • B. 

      6,12,18

    • C. 

      6,18,12

    • D. 

      8,16,12

    • E. 

      18,48,36


  • 78. 
    Which of the following statements concerning chloroplasts is false?
    • A. 

      They are responsible for producing ATP in the cell

    • B. 

      They have both outer and inner membranes

    • C. 

      They have their own DNA

    • D. 

      They have an internal membrane system known as the thylakoid


  • 79. 
    How are the light-dependant and light-independant reactions of the photosystem related?
    • A. 

      The products of the light-independant reactions are used in the light-dependant reactions

    • B. 

      The products of the light-dependant reactions are used in light-independant reactions

    • C. 

      The products of light-independant reactions must be present for light-dependant reactions to take place.

    • D. 

      They are not related


  • 80. 
    Early investigators thought the oxygen produced by photosynthetic plants came from carbon dioxide.  In fact, it comes from ________.
    • A. 

      Water

    • B. 

      Glucose

    • C. 

      Air

    • D. 

      Electrons from NADPH


  • 81. 
    Why are there several structurally different pigments in the reaction centers of photosynthesis?
    • A. 

      Excited electrons must pass through several pigments before they can be transferred to electron acceptors of the electron transport chain

    • B. 

      This setup enables the plant to absorb light energy of a variety of wavelengths

    • C. 

      They enable the plant to absorb more photons from light energy, all of which are at the same wavelength

    • D. 

      They enable the reaction center to excite electrons to a higher energy level


  • 82. 
    What event accompanies energy absorbion by chlorophyll?
    • A. 

      ATP is synthesized from the energy absorbed

    • B. 

      A carboxylation reaction of the Carbon cycle occurs

    • C. 

      Electrons are stripped from NADPH

    • D. 

      An electron is excited


  • 83. 
    What is the difference between NAD+ and NADP?
    • A. 

      NAD+ functions as an electron transporter, whereas NADP does not

    • B. 

      NAD+ functions as a free-energy source for cells, whereas NADP does not

    • C. 

      Both function as electron carriers, but NADP has a phosphate group and NAD+ does not

    • D. 

      None of the above


  • 84. 
    As electrons are passed through the system of electron carriers associated with photosystem II, they lose energy.  What happens to this energy near the end of photosystem II?
    • A. 

      It is used to phosphorylate NAD+ to NADPH, the molecule that accepts electrons from photosystem I

    • B. 

      It is lost as heat

    • C. 

      It is used to establish and maintain a proton gradient

    • D. 

      All of the above


  • 85. 
    What is the main purpose of the light-dependant reactions of photosynthesis?
    • A. 

      To generate oxygen by "splitting" H2O

    • B. 

      To produce NADPH for use in respiration

    • C. 

      To produce NADPH and ATP

    • D. 

      To use ATP to make glucose


  • 86. 
    The electrons of photosystem II are excited and transferred to electron carriers.  From which molecule or structure do the photosystem II replacement electrons come?
    • A. 

      The electron carrier, plastocyanin

    • B. 

      Photosystem I

    • C. 

      Water

    • D. 

      Oxygen


  • 87. 
    Cellular respiration is the process by which:
    • A. 

      Oxygen is produced during metabolic activity

    • B. 

      Light energy is converted into kinetic energy

    • C. 

      Oxygen is used to transport chemical energy throughout the body

    • D. 

      Energy from the chemical bonds of food molecules is captured by an organism

    • E. 

      ATP molecules are converted into water and sugar


  • 88. 
    Energy used in cellular respiration can originate from:
    • A. 

      Carbohydrates and proteins only

    • B. 

      Carbohydrates only

    • C. 

      Fats only

    • D. 

      Proteins only

    • E. 

      Carbohydrates, proteins, and fats


  • 89. 
    In glycolysis, one molecule of glucose containing six carbons is converted to two molecules of _____ containing three carbons each.  This reaction also yields two molecules of _______ and two molecules of ________.
    • A. 

      Lactic acid; O2; acetaldehyde

    • B. 

      Pyruvate; ATP; NADH

    • C. 

      Acetyl-CoA; ADP; Pi

    • D. 

      Galactose; H2O; ATP

    • E. 

      Sucrose; lactic acid; FADH


  • 90. 
    During the Krebs cycle:
    • A. 

      The products of glycolysis are futher broken down, generating additional ATP and the high-energy electron carrier NADH

    • B. 

      The products of glycolysis are completely converted into ATP

    • C. 

      High-energy electron carriers pass their energy to molecules of sugar which store them as potential energy

    • D. 

      All of the above


  • 91. 
    Different steps in cellular respiration occur in different locations in the mitochondria.  Which of the following properly matches a step of respiration to its proper location?
    • A. 

      A gradiant of hydrogen ions phosphorylates ATP: inner mitochondrial membrane

    • B. 

      Molecule of CO2 released: matrix

    • C. 

      Energy transferred from NADH and FADH2 to ATP: inner mitochondrial membrane

    • D. 

      Two carbons manipulated through Krebs cycle: Matrix

    • E. 

      All of the above are correct matches between function and location


  • 92. 
    When ATP is hydrolyzed to ADP, what happens?
    • A. 

      Ribose is removed

    • B. 

      Two phosphates are removed

    • C. 

      Adenine is removed

    • D. 

      Three phosphates are removed

    • E. 

      One phosphate is removed


  • 93. 
    Most of the CO2 from the oxidation of glucose is released during __________.
    • A. 

      Glycolysis

    • B. 

      Electron transport

    • C. 

      Chemiosmosis

    • D. 

      The Krebs cycle


  • 94. 
    Where is most of the water in cellular respiration produced?
    • A. 

      During glycolysis

    • B. 

      In the Krebs cycle

    • C. 

      During fermentation

    • D. 

      In the electron transport chain


  • 95. 
    Two ATP molecules are expended in the energy investment phase of glycolysis.  Why is this energy needed to begin the process of glucose catabolism?
    • A. 

      It is needed because glycolysis is considered an exergonic process which always requires input of energy from ATP

    • B. 

      It is needed to generate the electron carrier NAD+

    • C. 

      It is needed to induce the enzymes of glycolysis

    • D. 

      Some energy must be invested to make the glucose molecule unstable and begin the process of catabolism


  • 96. 
    Which electron carrier(s) functions in the Krebs cycle?
    • A. 

      NAD+ only

    • B. 

      Both NAD+ and FAD

    • C. 

      The electron transport chain

    • D. 

      ATP

    • E. 

      Pyruvate


  • 97. 
    The first CO2 that is released during aerobic cellular respiration is _________.
    • A. 

      During glycolysis

    • B. 

      Between glycolysis and the Krebs cycle

    • C. 

      During the Krebs cycle

    • D. 

      Just after the Krebs cycle


  • 98. 
    Which of the following events takes place in the electron transport chain?
    • A. 

      Breakdown of glucose into two pyruvate molecules

    • B. 

      The breakdown of an acetyl group to carbon dioxide

    • C. 

      The extraction of energy from high-energy electrons remaining from glycolysis and the Krebs cycle

    • D. 

      None of the above


  • 99. 
    The electron transport chain ___________.
    • A. 

      Is a series of redox reactions

    • B. 

      Is a series of substitution reactions

    • C. 

      Is driven by ATP consumption

    • D. 

      Takes place in the cytoplasm


  • 100. 
    The energy of electron transport serves to move protons to the outer mitochondrial compartment.  How does this help the mitochondrion to produce energy?
    • A. 

      The hydrogen ions are transferred to oxygen in an energy-releaseing action

    • B. 

      The translocation of protons sets up the electrochemical gradiant that drives ATP synthesis in the mitochondria

    • C. 

      The protons pick up electrons from the electron transport chain on their way through the inner mitochondrial membrane

    • D. 

      The protons receive electrons from the NAD+ and FAD that are accepted by electrons in glycolysis and the Krebs cycle


  • 101. 
    If an atom has a charge of +1, which of the following must be true?
    • A. 

      It has two more protons than neutrons

    • B. 

      It has the same number of protons as electrons

    • C. 

      It has one more electron than it does protons

    • D. 

      It has one more proton than it does electrons


  • 102. 
    Why do chemical reactions tend to speed up when the concentration of the reactants is increased?
    • A. 

      The reactants move faster

    • B. 

      The reactants collide more often

    • C. 

      The reactants have greater energy

    • D. 

      All of the above apply


  • 103. 
    When the pH of a solution goes from 7 to 11 we know that ___________.
    • A. 

      The solution is now more basic

    • B. 

      H+ has decreased

    • C. 

      OH- has increased

    • D. 

      All of the above

    • E. 

      None of the above


  • 104. 
    Which statement best summarizes the essence of chemical evolution?
    • A. 

      Energy in the form of sunlight or heat was transformed into chemical energy in the form of bonds

    • B. 

      Instead of being radiated back to space, energy in the form of sunlight or heat was retained in the oceans and atmosphere because of water's high specific heat

    • C. 

      Entropy increased

    • D. 

      An increasing number of exothermic reactions occurred


  • 105. 
    An atom has six electrons in its valence shell.  How many single covalent bonds would you expect it to form in most circumstances?
    • A. 

      One

    • B. 

      Two

    • C. 

      Three

    • D. 

      Six


  • 106. 
    When are atoms most stable?
    • A. 

      When they have the fewest possible valence electrons

    • B. 

      When they have the maximum number of unpaired electrons

    • C. 

      When all of the electron orbitals in the valence shell are filled

    • D. 

      When all electrons are paired


  • 107. 
    Carbon is an important element for biology because ___________.
    • A. 

      Of the variety of carbon skeletons and functional groups that can be built on them

    • B. 

      It has very high electronegativity and forms highly stable bonds

    • C. 

      Carbon is so rare, organisms conserve it highly

    • D. 

      It has the ability to form six covalent bonds


  • 108. 
    The functional group (-OH) is called a __________.
    • A. 

      Sulfhydryl

    • B. 

      Ketone

    • C. 

      Aldehyde

    • D. 

      Hydroxyl

    • E. 

      Amino


  • 109. 
    Which of the following is NOT true of hydrogen bonds?
    • A. 

      Are very weak

    • B. 

      Are broken by decreased temperature

    • C. 

      Are broken by increased temperature

    • D. 

      Are important in the solvent properties of water

    • E. 

      None of the above


  • 110. 
    When the atoms involved in a covalent bond have the same electronegativity, what type of bond results?
    • A. 

      An ionic bond

    • B. 

      A hydrogen bond

    • C. 

      A nonpolar covalent bond

    • D. 

      A polar covalent bond


  • 111. 
    Water has a high specific heat because of the __________.
    • A. 

      Polar covalent bonds formed between the oxygen and a hydrogen of a single water molecule

    • B. 

      Ionic bonds formed between the hydrogen of one water molecule and the oxygen of another water molecule

    • C. 

      Hydrogen bonds formed between the hydrogen of one water molecule and the oxygen of another water molecule

    • D. 

      Covalent bonds formed between the hydrogen of one water molecule and the oxygen of another water molecule


  • 112. 
    Polymerization of monomers often occurs by removing a hydrogen from one monomer and hydroxyl from the other to remove a water molecule as the monomers join.  This type of reaction is called
    • A. 

      Hydrolysis

    • B. 

      Condensation reaction

    • C. 

      Hydrogenation reaction

    • D. 

      Glycolysis reaction


  • 113. 
    What aspects of amino acid structure vary among different amino acids?
    • A. 

      The long carbon-hydrogen tails of the molecule

    • B. 

      The presence of a central C atom

    • C. 

      The components of the R group

    • D. 

      The glycerol molecule that forms the backbone of the amino acid


  • 114. 
    Proteins in biological systems ______.
    • A. 

      Store genetic information

    • B. 

      Link together to form the plasma membrane of cells

    • C. 

      May be enzymes that catalyze reactions

    • D. 

      Serve as a way to store energy long-term in the body


  • 115. 
    The lock-and-key analogy for enzymes applies to the ___________.
    • A. 

      Specificity of enzyme primary, secondary, and tertiary structure

    • B. 

      Specificity of enzymes interacting with ions

    • C. 

      Specificity of enzymes binding to their substrate

    • D. 

      Specificity of enzymes interacting with water


  • 116. 
    A peptide bond __________.
    • A. 

      Forms between the functional groups of different amino acids

    • B. 

      Forms between the central carbon and the amino group of a single amino acid

    • C. 

      Forms between a carboxyl group of one amino acid and the amino group of the next amino acid

    • D. 

      Forms between the phosphate of one amino acid and the carboxyl group of the next amino acid


  • 117. 
    A beta-pleated sheet in a protein is an example of a:
    • A. 

      Primary structure

    • B. 

      Secondary structure

    • C. 

      Tertiary structure

    • D. 

      Quaternary structure


  • 118. 
    In cells, the activity of enzymes is often regulated by other molecules.  Why is this necessary?
    • A. 

      Because it is unlikely that all reaction products are required all of the time

    • B. 

      Because other molecules are necessary to prevent enzymes from denaturing

    • C. 

      Because each enzyme has multiple functions

    • D. 

      All of the above


  • 119. 
    All of the proteins have directionality.  This means that
    • A. 

      The C-terminus, or the cytosol end, always faces to the right, and the G-terminus, or the guanine terminus, always faces to the left

    • B. 

      The 5 prime end of the protein always faces up and the 3 prime end of the protein always faces down

    • C. 

      The N-terminus, or amino groups, are always placed left, while the C-terminus, or caboxyl groups are always placed on the right

    • D. 

      The phosphate hydrophilic head always faces out, and the hydrophobic tail always faces in


  • 120. 
    The functional groups of amino acids ______________.
    • A. 

      Are always charged

    • B. 

      May be hydrophobic or hydrophilic

    • C. 

      Only contain C,H, and O

    • D. 

      Are identical in different types of amino acids


  • 121. 
    How do the alpha and beta forms of glucose differ?
    • A. 

      Their ring structures differ in the location of a hydroxyl group

    • B. 

      Their linear structures differ in the location of a hydroxyl group

    • C. 

      The oxygen atom inside the ring is located in a different position


  • 122. 
    The major role of carbohydrates in animals is
    • A. 

      Energy storage

    • B. 

      Insulation

    • C. 

      Cushion

    • D. 

      All of the above

    • E. 

      None of the above


  • 123. 
    What is the difference between an aldose sugar and a ketose sugar?
    • A. 

      The number of carbons

    • B. 

      The position of the hydroxyl groups

    • C. 

      The position of the carbonyl group

    • D. 

      One is a ring form, the other is a linear chain


  • 124. 
    If you were going to develop a new antibiotic against bacteria, you would probably need to become an expert on which of these carbohydrates?
    • A. 

      Glycogen

    • B. 

      Chitin

    • C. 

      Peptidoglycan

    • D. 

      Cellulose

    • E. 

      Starch


  • 125. 
    Which of these best reflects the following relationship: monosaccharide vs polysaccharide?
    • A. 

      Glucose vs glycogen

    • B. 

      Glucose vs fructose

    • C. 

      1,4-glycosidic linkage vs 1,6-glycosidic linkage

    • D. 

      Alpha-linkage vs beta-linkage


  • 126. 
    A glycosidic linkage is analogous to which of the following in proteins?
    • A. 

      An amino group

    • B. 

      A peptide bond

    • C. 

      A disulfide bond

    • D. 

      A beta-pleated sheet


  • 127. 
    Nucleic acids are polymers made up of which of the following monomers?
    • A. 

      Nucleotides

    • B. 

      Sugars

    • C. 

      Amino acids

    • D. 

      Nitrogenous bases


  • 128. 
    Nucleic acids have a definite polarity, or directionality.  Stated another way, one end of the molecule is different from the other end.  How are these ends described?
    • A. 

      One end has a hydroxyl group on the 2 carbon; the other end has a hydrogen atom on the 2 carbon

    • B. 

      One end contains a nitrogenous base; the other end lacks it

    • C. 

      One end has an unlinked 3 carbon; the other end has an unlinked 5 carbon

    • D. 

      One end has one phosphate group; the other end has two phosphate groups


  • 129. 
    Why is it that RNA can catalyze reactions but DNA cannot?
    • A. 

      The sugar of RNA is much more reactive than the sugar of DNA due to an extra oxygen

    • B. 

      The bases of RNA are mouch more reactive than the bases of DNA

    • C. 

      The phosphate groups of RNA are much more reactive than the phosphate groups of DNA

    • D. 

      The primary structure of RNA is fundamentally different than the primary structure of DNA


  • 130. 
    Which of the following is a difference between RNA and DNA?
    • A. 

      One is typically single stranded and the other is typically triple stranded

    • B. 

      One contains guanine and the other does not

    • C. 

      One contains ribose sugar and the other contains a deoxyribose sugar

    • D. 

      One is made from nucleotide monomers and the other one is not


  • 131. 
    Which of the following is not one of the three components that make up a nucleotide?
    • A. 

      Phosphate

    • B. 

      Glycerol

    • C. 

      Five carbon sugar

    • D. 

      Nitrogenous base


  • 132. 
    Which of the following includes all of the pyrimidines found in RNA and/or DNA?
    • A. 

      Cytosine and uracil

    • B. 

      Cytosine and thymine

    • C. 

      Cytosine, uracil, and thymine

    • D. 

      Cytosine, uracil, and guanine


  • 133. 
    When nucleotides polymerize to form a nucleic acid __________.
    • A. 

      A covalent bond forms between the sugar of one nucleotide and the phosphate of a second

    • B. 

      A hydrogen bond forms between the sugar of one nucleotide and the phosphate of a second

    • C. 

      Covalent bonds form between the bases of two nucleotides

    • D. 

      Hydrogen bonds form between the bases of two nucleotides


  • 134. 
    The term phospholipid can be best described by which of the following?
    • A. 

      A nonpolar lipid molecule that is made polar by the addition of a phosphate

    • B. 

      A nonpolar lipid molecule that is made amphipathic by the addition of a phosphate

    • C. 

      A polar lipid molecule that fully interacts with water

    • D. 

      A polar lipid molecule that fully repels water


  • 135. 
    What most distinguishes lipids from other biomolecules is ___________.
    • A. 

      That only lipids contain hydrogen atoms

    • B. 

      Their molecule weight (size)

    • C. 

      That they are not soluble in water

    • D. 

      The various functional groups contained in lipids


  • 136. 
    How do phospholipids interact with water molecules?
    • A. 

      The polar heads avoid water; the nonpolar tails attract water (because water is polar and opposites attract)

    • B. 

      The phospholipids don't interact with water because water is polar and lipids are nonpolar

    • C. 

      The polar heads interact with water; the nonpolar tails do not

    • D. 

      Phospholipids dissolve in water


  • 137. 
    What type of bond results when the hydroxyl group on glycerol reacts with the carboxylic group on a fatty acid?
    • A. 

      Ester linkage

    • B. 

      Hydrocarbon

    • C. 

      Peptide bond

    • D. 

      Glycosidic bond


  • 138. 
    Which of the following is the best explanation for why vegetable oil is a liquid at room temperature while animal fats are solid?
    • A. 

      Vegetable oil has more double bonds than animal fats

    • B. 

      Vegetable oil has fewer double bonds than animal fats

    • C. 

      Animal fats have no amphipathic character

    • D. 

      Vegetable oil has longer fatty-acid tails than animal fats have


  • 139. 
    Under what circumstances does membrane transport always require energy?
    • A. 

      Whenever molecules are moved that are too large to pass through the phospholipid bilayer membrane

    • B. 

      Whenever a solute needs to be moved from low concetration to high concentration through a phospholipid bilayer membrane

    • C. 

      Whenever a solute is charged, such as an ion, and is moved through a phospholipid bilayer membrane

    • D. 

      Whenever a molecule is polar and is moved through a phospholipid bilayer membrane


  • 140. 
    What will happen to a red blood cell which has an internal ion concentration of about 0.9% if it is placed into a beaker of pure water?
    • A. 

      Nothing

    • B. 

      The cell would shrink because the water in the beaker is hypotonic relative to the cytoplasm of the RBC

    • C. 

      The cell would shrink because the water in the beaker is hypertonic relative to the cytoplasm of the RBC

    • D. 

      The cell would swell because the water in the beaker is hypotonic relative to the cytoplasm of the RBC


  • 141. 
    Which of the following molecules must move across the nuclear membrane after being synthesized from a DNA sequence and is then translated by a ribosome (in eukaryotes)?
    • A. 

      MRNA

    • B. 

      DNA

    • C. 

      RRNA

    • D. 

      TRNA


  • 142. 
    What molecule serves as a link between the information-containing macromolecule DNA and protein synthesis?
    • A. 

      RRNA

    • B. 

      TRNA

    • C. 

      MRNA

    • D. 

      Ribosome


  • 143. 
    How do eukaryotic codons and prokaryotic codons compare?
    • A. 

      Prokaryotic codons usually contain different bases than those of eukaryotes

    • B. 

      Prokaryotic codons usually specify different amino acids than those of eukaryotes

    • C. 

      The translation of codons is mediated by tRNAs in eukaryotes, but translation requires no intermediate molecules such as tRNAs in prokaryotes

    • D. 

      Codons are a nearly universal language among all organisms


  • 144. 
    In the process of transcription _________.
    • A. 

      DNA is replicated

    • B. 

      RNA is synthesized

    • C. 

      Proteins are syntesized

    • D. 

      MRNA attaches to ribosomes


  • 145. 
    Which of the following is NOT synthesized from a DNA template?
    • A. 

      Messenger RNA

    • B. 

      Amino acids

    • C. 

      TRNA

    • D. 

      Ribosomal RNA


  • 146. 
    How might a single base deletion in the sequence of a gene affect the amino acid sequence of a protein encoded by the gene and why?
    • A. 

      Only a single amino acid could change, because the reading frame is unaffected

    • B. 

      The amino acid sequence would be substantially altered, because the reading frame would change with a single base deletion

    • C. 

      It is not possible for a single base deletion to affect protein structure, because each codon is three bases long


  • 147. 
    Given the DNA template TTTTT, which of the following bases would you find in a complementary RNA strand and where would it be synthesized?
    • A. 

      AAAAA; nucleus

    • B. 

      UUUUU; nucleus

    • C. 

      AAAAA; ribosome

    • D. 

      UUUUU; ribosome


  • 148. 
    What does it mean when we say the genetic code is redundant?
    • A. 

      A single codon can specify the addition of more than one amino acid

    • B. 

      The genetic code is different for different domains of organisms

    • C. 

      The genetic code is universal

    • D. 

      More than one codon can specify the addition of the same amino acid


  • 149. 
    Which of the following molecules is not required for translation?
    • A. 

      MRNA

    • B. 

      TRNA

    • C. 

      DNA

    • D. 

      RRNA


  • 150. 
    How does the simple primary and secondary structure of DNA hold the information needed to code for the many features of multicellular organisms?
    • A. 

      The hydrogen bonding among backbone constituents carries coded information

    • B. 

      The base sequence of DNA carries all the information needed to code for proteins

    • C. 

      The width of the double helix changes at each gene due to differences in hydrogen bonds

    • D. 

      The amino acids that make up the DNA molecule contain the information needed to make cellular proteins


  • 151. 
    What is the difference between the leading strand and the lagging strand in DNA replication?
    • A. 

      The leading strand is synthesized in the 3'-5' direction in a discontinuous fashion, while the lagging strand is synthesized in the 5'-3' direction in a continuous fashion

    • B. 

      The leading strand requires an RNA primer, whereas the lagging strand does not

    • C. 

      The leading strand is synthesized continuously in the 5'-3' direction, while the lagging strand is synthesized discontinuously in the 5'-3' direction

    • D. 

      There are different DNA polymerases involved in elongation of the leading strand and the lagging strand


  • 152. 
    DNA is synthesized through a process known as semiconservative replication.  What is the template?
    • A. 

      Single stranded binding proteins

    • B. 

      DNA polymerase contains the template needed

    • C. 

      One strand of the DNA molecule

    • D. 

      An RNA molecule


  • 153. 
    In the polymerization of DNA, a phosphodiester bond is formed between a phosphate group of the nucleotide being added and _______ of the last nucleotide in the polymer.
    • A. 

      The 5' phosphate

    • B. 

      C6

    • C. 

      The 3' OH

    • D. 

      A nitrogen from the nitrogen-containing base


  • 154. 
    What is the major difference between eukaryotic DNA replication and prokaryotic DNA replication?
    • A. 

      Prokaryotic replication does not require a primer

    • B. 

      Prokaryotic chromasomes have a single origin of replication while eukaryotic chromasomes have multiple origins of replication

    • C. 

      DNA polymerase III of eukaryotes has both endonuclease and exonuclease activity, while that of prokaryotes has only exonuclease activity

    • D. 

      DNA polymerases of prokaryotes can add nucleotides to both 3' and 5' ends of DNA strands, while those of eukaryotes function only in the 5'-3' direction


  • 155. 
    During DNA synthesis which of the following structures breaks hydrogen bonds between complementary bases?
    • A. 

      DNA polymerase

    • B. 

      Helicase

    • C. 

      Sliding clamp

    • D. 

      Topoisomerase

    • E. 

      SS binding proteins


  • 156. 
    During DNA synthesis which of the following structures is responsible for extending an Okazaki fragment?
    • A. 

      DNA polymerase I

    • B. 

      DNA polymerase III

    • C. 

      Helicase

    • D. 

      Primase


  • 157. 
    Put the following steps of DNA replication in chronological order: 1. single stranded binding proteins (SSBPs) attach to DNA strands 2. hydrogen bonds between base pairs of antiparallel strands are broken 3. Primase binds to the site of origin 4. DNA polymerase binds to the template strand 5. an RNA primer is created
    • A. 

      1,2,3,4,5

    • B. 

      2,1,3,5,4

    • C. 

      3,2,1,5,4

    • D. 

      3,1,2,4,5


  • 158. 
    During DNA synthesis, which structure is responsible for stabilizing DNA in its single-stranded form?
    • A. 

      DNA polymerase

    • B. 

      Helicase

    • C. 

      Sliding clamp

    • D. 

      Topoisomerase

    • E. 

      SS binding proteins


  • 159. 
    What is a telomere?
    • A. 

      The mechanism that holds two sister chromatids together

    • B. 

      DNA replication during telophase

    • C. 

      The site of origin of DNA replication

    • D. 

      The ends of linear chromasomes containing no genes


  • 160. 
    Telomere shortening puts a limit on the number of times a cell can divide.
    • A. 

      True

    • B. 

      False


  • 161. 
    If RNA polymerase is missing __________ then transcription would not begin.
    • A. 

      Amino acids

    • B. 

      MRNA

    • C. 

      Sigma

    • D. 

      Helicase

    • E. 

      ATP


  • 162. 
    A primary transcript in the nucleus of a eukaryotic cell is __________ the functional mRNA, while a primary transcript in a prokaryotic cell is ________ the functional mRNA.
    • A. 

      The same size as; the same size as

    • B. 

      Larger than; the same size as

    • C. 

      Larger than; smaller than

    • D. 

      The same size as; larger than


  • 163. 
    Which of the following is part of a DNA molecule?
    • A. 

      Sigma

    • B. 

      The holoenzyme

    • C. 

      Initiation factors

    • D. 

      Promoters


  • 164. 
    David Pribnow studied the base sequences of promoters in bacteria and bacterial viruses.  He found two conserved regions in these promoters (the -10 box and the -35 box).  What is the function of these two regions of the promoter?
    • A. 

      They separate the two DNA strands

    • B. 

      They bind the sigma subunit that is associated with RNA polymerase

    • C. 

      They attach the correct nucleotide triphosphate to the template DNA strand


  • 165. 
    Put the following events of transcription in chronological order: 1. Sigma binds to the promoter region 2. the double helix of DNA is unwound, breaking hydrogen bonds between complementary strands 3. sigma binds to RNA polymerase 4. sigma is released 5. transcription begins
    • A. 

      2,3,4,5

    • B. 

      2,3,1,4,5

    • C. 

      3,1,2,5,4

    • D. 

      3,2,1,4,5


  • 166. 
    Sigma plus the core enzyme of RNA polymerase is called the:
    • A. 

      Transcriptor

    • B. 

      Holoenzyme

    • C. 

      Translator

    • D. 

      Spliceosome


  • 167. 
    The promoter region for transcription in eukaryotic cells is referred to as the:
    • A. 

      -10 box

    • B. 

      TATA box

    • C. 

      Holoenzyme region

    • D. 

      Sigma box


  • 168. 
    What is the function of the group of amino acids on the RNA polymerase, called the rudder?
    • A. 

      It provides the energy required for formation of phosphodiester bonds in the elongating RNA molecule

    • B. 

      It helps unwind and open the DNA molecule

    • C. 

      It moves template and non-template strands of DNA through channels inside the enzyme

    • D. 

      It helps sigma bind to the RNA polymerase molecule


  • 169. 
    During elongation, RNA polymerase has three predominant channels, or grooves.  These channels provide sites for all of the following EXCEPT ________.
    • A. 

      A site for the double-stranded DNA molecule

    • B. 

      A site for the entry of ribonucleoside triphosphates

    • C. 

      A site for the exit of tRNAs

    • D. 

      A site for the growing RNA strand


  • 170. 
    How are RNA hairpin turns related to termination?
    • A. 

      The turns are formed from complementary base pairing and cause separation of the RNA transcript and RNA polymerase

    • B. 

      A three-base repeat signals a stop sequence, and the RNA transcript is released

    • C. 

      Release factors bind to the sites on the hairpin turn, causing release of the RNA transcript

    • D. 

      The hairpin turn prevents more nucleoside triphosphates from entering the active site of the enzymes, effectively shutting off the process of polymerization


  • 171. 
    Ribosomes can attach to prokaryotic messenger RNA ____________.
    • A. 

      Once post-transcriptional modification is complete

    • B. 

      Before transcription is complete

    • C. 

      Once replication is complete

    • D. 

      Once the primary transcript has been released from RNA polymerase


  • 172. 
    Which of the following is NOT one of the steps in initiation of translation?
    • A. 

      Binding of the large ribosomal subunit to the small ribosomal subunit

    • B. 

      Binding of tRNA carrying formyl methionine to the start codon and small ribosomal subunit

    • C. 

      Recognition and binding of mRNA by the small ribosomal subunit

    • D. 

      Formation of a peptide bond


  • 173. 
    The combination of a tRNA molecule and its properly connected and properly associated amino acid is referred to as the:
    • A. 

      Aminoacyl tRNA

    • B. 

      Modified tRNA

    • C. 

      Holo tRNA

    • D. 

      Sigma complex tRNA


  • 174. 
    What is the function of the AGU on the loop of the tRNA?
    • A. 

      It attaches to the amino acid

    • B. 

      It temporarily basepairs with the codon of mRNA

    • C. 

      It stabilizes the tRNA-amino acid complex

    • D. 

      It is the active site of this ribozyme


  • 175. 
    If the DNA code for a particular amino acid is AGT, then the anticodon on the tRNA would be ____________.
    • A. 

      AGT

    • B. 

      TCA

    • C. 

      UCA

    • D. 

      AGU


  • 176. 
    Anti-codons are part of _________.
    • A. 

      Protein

    • B. 

      MRNA

    • C. 

      TRNA

    • D. 

      RRNA


  • 177. 
    In transcription, the zipper mechanism of the RNA polymerase serves the function of:
    • A. 

      Steering the template and non-template strands of DNA through the channels inside the enzyme

    • B. 

      Direction RNA nucleotides to the template

    • C. 

      Separating the newly synthesized RNA from the DNA template

    • D. 

      Rewinding the DNA molecule back together after transcription


  • 178. 
    Which of the following does not occur in post-transcriptional modifications occurring in eukaryotic mRNAs?
    • A. 

      Addition of a poly-A tail

    • B. 

      Addition of a methyl-guanosine cap

    • C. 

      Removal of introns

    • D. 

      RNA polymerase termination


  • 179. 
    In initiation of translation, the very first aminoacyl tRNA to attach to the mRNA strand is
    • A. 

      Various depending on the first codon

    • B. 

      The f-Met

    • C. 

      Tryptophan

    • D. 

      Valine


  • 180. 
    Put the following events of elongation in prokaryotic translation in chronological order: 1. binding of mRNA with small ribosomal subunit 2. recognition of initiation codon 3. complementary base pairing between initiator codon and anticodon of initator tRNA 4. base pairing of the mRNA codon following the initator codon with its complementary tRNA 5. attachment of the large subunit
    • A. 

      1,2,3,4,5

    • B. 

      2,1,4,3,5

    • C. 

      5,4,3,2,1

    • D. 

      1,2,3,5,4


  • 181. 
    Which site in the ribosome holds a tRNA attached to the amino acid forming a peptide bond with the amino acid in the previous site?
    • A. 

      E site

    • B. 

      P site

    • C. 

      A site

    • D. 

      Small subunit


  • 182. 
    During elongation, which site in the ribosome represents the location where a codon is being read?
    • A. 

      E site

    • B. 

      P site

    • C. 

      A site

    • D. 

      Small subunit


  • 183. 
    In translation, what signals termination of the process?
    • A. 

      A stop codon is exposed in the A site and a release factor enters the A site of the ribosome

    • B. 

      A stop codon signals a hairpin loop to be created in the protein

    • C. 

      A stop codon signals an f-Met amino acid to enter the A site of the ribosome

    • D. 

      A sigma releases from the ribosome subunit


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