1. The molecular "machines" (those components that do things) of the cell are the
a. proteins.
b. carbohydrates
c. DNA
d. energy
e. homeostasis
2. Silicon is an element, look it up in the Periodic table and answer the following questions
a)What is its chemical symbol?
b)How many neutrons does it have?
c)How many protons?
d)How many electrons in its second shell?
3. A mutation is a change in
a. RNA sequence
b. the developmental pattern in an organism.
c. appearance and behavior of a cell
d. DNA conformation
e. DNA sequence
4. _________ is the main molecule providing energy for intracellular (within a cell) processes.
5. The chemical processes in the living cell are collectively called
a. adaptation.
b. homeostasis.
c. evolution.
d. respiration.
e. metabolism.
6. The ability to acquire, store, transfer, or utilize energy is called
a. biochemistry.
b. photosynthesis.
c. metabolism.
d. respiration.
e. phosphorylation.
7. Which is the smallest unit of life that can exist as a separate entity?
a. a cell
b. a molecule
c. an organ
d. a population
e. an ecosystem
8. Which of the following might be defined as "the physical and biological components living in the same limited type of environment "
a. ecosystem
b. community
c. biosphere
d. organism
e. population
9. If the atomic weights of carbon, oxygen and hydrogen are 12, 16, and 1 respectively, the gram molecular weight of ethyl alcohol C expressed in grams is
a. 24 grams.
b. 28 grams.
c. 52 grams.
d. 168 grams.
e. 180 grams.
10. A salt will dissolve in water to form
a. acids.
b. gases.
c. ions.
d. bases.
e. polar solvents.
11. Amino acids are the building blocks for
a. proteins.
b. steroids.
c. lipids.
d. nucleic acids.
e. carbohydrates.
12. The formation of large molecules from small repeating units is known as what kind of reaction?
a. oxidation
b. reduction
c. condensation
d. hydrolysis
e. decarboxylation
13. The breakdown of large molecules by the enzymatic addition of water is an example of what kind of reaction?
a. oxidation
b. reduction
c. condensation
d. hydrolysis
e. decarboxylation
14. Which is a "building block" of nucleic acids?
a. glycerol
b. nucleotide
c. simple sugar
d. monosaccharide
e. either simple sugars or monosaccharides
15. Which substance is the most common in cells?
a. carbohydrates
b. salts and minerals
c. proteins
d. fats
e. water
16. Which of the following is composed of a 1:2:1 ratio of carbon to hydrogen to oxygen?
a. carbohydrate
b. protein
c. lipid
d. nucleic acid
e. steroid
17. Glucose and ribose
a. have the same number of carbon atoms.
b. have the same structural formulas.
c. are the two components of sucrose.
d. are monosaccharides.
e. are molecules whose atoms are arranged the same way.
18. Which element is NOT characteristic of the primary structure of proteins?
a. sulfur
b. carbon
c. phosphorus
d. oxygen
e. nitrogen
19. Proteins may function as
a. structural units.
b. hormones.
c. storage molecules.
d. transport molecules.
e. all of these
20. What kind of bond exists between two amino acids in a protein?
a. peptide
b. ionic
c. hydrogen
d. amino
e. hemiacetyl
21. The sequence of amino acids is the __________ structure of proteins.
a. primary
b. secondary
c. tertiary
d. quaternary
e. stereo
22. The secondary structure of proteins can be
a. helical.
b. sheet like.
c. globular.
d. the sequence of amino acids.
e. both helical and sheet like.
23. When a hen's egg is cooked for breakfast, which of the following statements does not apply?
a. High temperature breaks the hydrogen bonds.
b. Gentle cooling will reverse the denaturation that has occurred.
c. The covalent bonds are not broken.
d. Denaturation has resulted in a change from "runny" to "semi-solid."
24. Which of the following is NOT found in every nucleic acid?
a. ribose
b. phosphate group
c. purine
d. pyrimidine
e. all of these are characteristic of every nucleotide
25. Nucleotides contain what kind of sugars?
a. three-carbon
b. four-carbon
c. five-carbon
d. six-carbon
e. seven-carbon
26. DNA
a. is one of the adenosine phosphates.
b. is one of the nucleotide coenzymes.
c. contains protein-building instructions.
d. all of these
e. none of these
27. Which statement is NOT true?
a. Membranes are often perforated by proteins that extend through both sides of the membrane.
b. Some membranes have proteins with channels or pores that allow for the passage of hydrophilic substances.
c. Hydrophilic substances have an easier time passing through membranes than hydrophobic substances do.
d. The current concept of a membrane can be best summarized by the fluid mosaic model.
e. The lipid bilayer serves as a hydrophobic barrier between two fluid regions.
28. Which of the following are made of two subunits and are composed of RNA and protein?
a. Golgi
b. mitochondria
c. chloroplasts
d. ribosomes
e. endoplasmic reticula
29. These are the primary cellular sites for the recapture of energy from carbohydrates
a. Golgi bodies
b. ribosomes
c. mitochondria
d. lysosomes
e. endoplasmic reticula
30. Cell part responsible for maintaining cell shape, internal organization, and cell movements is the
a. vesicle.
b. nucleus.
c. endoplasmic reticulum.
d. cytoskeleton.
e. ribosome.
31. What cell organelle is found in plant cells but NOT in animal cells?
a. nucleoplasm
b. central vacuole
c. plasma membrane
d. Golgi body
e. microtubules
32. An organelle found in the nucleus is a
a. plastid.
b. vacuole.
c. microvillus.
d. nucleolus.
e. basal body.
33. Which of the following is NOT true concerning the nuclear envelope?
a. It has two lipid bilayers.
b. There are pores in the membrane.
c. Ribosomal subunits can pass out of the nucleus.
d. DNA molecules are transported out through the pores.
e. Protein filaments are attached to the inner surface.
34.-36. Describe a "chromosome" What does is it made of, what does it do? Here I want more than DNA and proteins - I want to know about nucleosomes and how you can fit 3 feet of DNA into a cell to small to see?
37. Which organelles contain DNA?
a. nuclei.
b. mitochondria.
c. chloroplast
d. all the above
e. only the nucleus.
38. The number of membranes composing a mitochondrion is
a. one.
b. two.
c. three.
d. four.
e. unknown.
39. The inner membranes of mitochondria are called
a. filaments.
b. cilia.
c. chromatin.
d. cristae.
e. centrioles.
40. Which organelles contain RNA?
a. nuclei.
b. mitochondria.
c. ribosomes
d. all the above
e. only the nucleus.
41. The number of membranes composing a mitochondrion is
a. one.
b. two.
c. three.
d. four.
e. different for different mitochondria.
42. The inner membranes of mitochondria are called
a. filaments
b. cilia.
c. chromatin.
d. cristae.
e. centrioles.
43. According to the first law of thermodynamics
a. although energy in the universe is constant, energy in an earthly system may accumulate.
b. the amount of energy in the universe grows constantly.
c. chemical reactions create or destroy energy.
d. energy can not change from one form to another.
e. all of these
44. The second law of thermodynamics holds that
a. matter can neither be created nor destroyed.
b. energy can neither be created nor destroyed.
c. energy of one form is converted to a less concentrated form whenever energy is transformed or transferred.
d. entropy decreases with time.
e. none of these
45. The removal of electrons from a compound is known as
a. dehydration.
b. oxidation.
c. reduction.
d. phosphorylation.
e. a nonreversible chemical reaction.
46. When NAD+ combines with hydrogen, the NAD+ becomes
a. reduced.
b. oxidized.
c. phosphorylated.
d. denatured.
e. none of these
47. Which reaction is NOT an exergonic reaction?
a. protein synthesis
b. digestion
c. fire
d. respiration
e. movement
48. Although it its too simple an explanation, the concept of a key fitting into a lock is descriptive of the
a. inhibition of enzymes by small molecules.
b. fit of coenzymes to enzymes.
c. matching of enzyme with substrate.
d. regeneration of ATP from ADP.
e. stepwise cascade of electrons in the oxidation-reduction reactions.
49. Which of the following may show enzymatic activity?
a. lipids
b. proteins
c. DNA
d. lipids and proteins
e. proteins and carbohydrates
50. Which of the following is NOT true of enzyme behavior?
a. Enzyme shape may change during catalysis.
b. The active site of an enzyme orients its substrate molecules, thereby promoting interaction of their reactive parts.
c. All enzymes have an active site where substrates are temporarily bound.
d. Each enzyme can catalyze a wide variety of different reactions.
e. none of these
51. Enzymes
a. are very specific.
b. act as catalysts.
c. are organic molecules.
d. have special shapes that control their activities.
e. all of these
52. The active site of an enzyme
a. is where the coenzyme is located.
b. is a specific bulge or protuberance on an enzyme.
c. is a groove or crevice in the structure of the enzyme.
d. will react with only one substrate no matter how many molecules may resemble the shape of the substrate.
e. rigidly resists any alteration of its shape.
53. Enzymes increase the rate of a given reaction by lowering what kind of energy?
a. combination
b. activation
c. thermal
d. electrical
e. solar
54. When a cell undergoes mitosis
a. the daughter cells have identical genes.
b. the daughter cell has genes identical to those of the mother cell that produced it.
c. the amount of cytoplasm in the mother cell and in each of the daughter cells is equal.
d. there is an exact duplication and division of all of the organelles between daughter cells.
e. both the daughter cells have identical genes and the daughter cell has genes identical to those of the mother cell that produced it is true.
55. In mitosis, if a parent cell has 16 chromosomes, each daughter cell will have how many chromosomes?
a. 64
b. 32
c. 16
d. 8
e. 4
56. Chromatids that are attached at the centromere are called what kind of chromatids?
a. mother
b. daughter
c. sister
d. programmed
e. either mother or daughter but not sister nor programmed
57. A Cells two sets of genetic information are described by the term
a. polyploid.
b. diploid.
c. triploid.
d. haploid.
e. tetraploid.
58. DNA replication occurs
a. between the gap phases of interphase.
b. immediately before prophase of mitosis.
c. during prophase of mitosis.
d. during prophase of meiosis.
e. at any time during cell division.
59. The spindle apparatus is made of
a. Golgi bodies.
b. microtubules.
c. endoplasmic reticulum.
d. nucleoprotein.
e. chromatids.
60. In eukaryotic cells, which can occur during mitosis?
a. the duplication of chromatids
b. the replication of DNA
c. pairing of homologous chromosomes
d. fragmentation and disappearance of nuclear envelope and nucleolus
e. all of these
61. The chromosomes are aligned at the spindle equator during
a. anaphase.
b. metaphase.
c. interphase.
d. prophase.
e. telophase.
62. The spindle apparatus becomes visible during
a. anaphase.
b. metaphase.
c. interphase.
d. prophase.
e. telophase.
63. The chromosomes detach from one another and become visibly separated during
a. anaphase.
b. metaphase.
c. interphase.
d. prophase.
e. telophase.
64. The chromosomes are moving to opposite poles during
a. anaphase.
b. metaphase.
c. interphase.
d. prophase.
e. telophase.
65. The chromosomes have arrived at opposite poles during
a. anaphase.
b. metaphase.
c. interphase.
d. prophase.
e. telophase.
66. Strictly speaking, mitosis and meiosis are divisions of the
a. nucleus.
b. cytoplasm.
c. chromosomes.
d. only nucleus and chromosomes.
e. nucleus, cytoplasm, and chromosomes.
67. In which of the stages below does the chromosome consist of two DNA molecules?
I. metaphase II. telophase
III. prophase IV. anaphase
a. III and IV
b. I, III, and IV
c. I and III
d. I, II, and III
e. I, II, III, and IV
68. Cytokinesis (cytoplasmic division)
a. in animal cells begins with various deposits of material associated with groups of microtubules at each pole of the nucleus.
b. in animal cells occurs when the plasma membrane is pulled inward by a ring of actin filaments at the spindle equator.
c. usually accompanies nuclear division.
d. begins with the deposition of a very rigid lipid bilayer that cuts the cell in two.
e. all of these
69. The distribution of cytoplasm to daughter cells is accomplished during
a. prokaryotic fission.
b. mitosis.
c. meiosis.
d. cytokinesis (cytoplasmic division).
e. karyokinesis.
70. Proteins associated with DNA in eukaryotes are
a. repressors.
b. tryptophans.
c. histones.
d. nucleosomes.
e. operons.
71. Histone-DNA units are called
a. polysomes.
b. ribosomes.
c. nucleosomes.
d. chromocenters.
e. vesicles.
72.-75. Matching. Choose the one most appropriate answer for each.
a. _____ centriole
b. _____ centromere
c. _____ chromatid
d. _____ cytokinesis
e. _____ metaphase
f. _____ microtubules
g. _____ prophase
h. _____ telophase 1. cytoplasm apportioned between the two daughter cells
2. final phase of mitosis; daughter nuclei re-form
3. two sister chromatids are joined here
4. chromosomes condense and mitotic spindle begins to form
5. chromosomes line up at spindle equator
6. sister chromatids separate; move to opposite spindle poles now
7. about 25 mm in diameter; form mitotic spindle
8. half of a chromosome in prophase
9. in pairs in some eukaryotic cells; move to poles during spindle formation
76. Genes are
a. located on chromosomes.
b. inherited in the same way as chromosomes.
c. arranged in linear sequence on chromosomes.
d. assorted independently during meiosis.
e. all of these
77. Chromosomes other than those involved in sex determination are known as
a. nucleosomes.
b. heterosomes.
c. alleles.
d. autosomes.
e. liposomes.
78. DNA coding regions that affect the same trait are called
a. homologues.
b. alleles.
c. autosomes.
d. loci.
e. gametes.
79. The location of a gene on a chromosome is its
a. centromere.
b. locus.
c. autosome.
d. allele.
e. none of these
80. A karyotype
a. compares one set of chromosomes to another.
b. is a visual display of chromosomes arranged according to size.
c. is a photograph of cells undergoing mitosis during anaphase.
d. of a normal human cell shows 48 chromosomes.
e. cannot be used to identify individual chromosomes beyond the fact that two chromosomes are homologues.
81. In karyotyping, individual chromosomes may be distinguished from others by
a. a comparison of chromosome lengths.
b. bands produced on chromosomes by differential staining.
c. the position of centromeres.
d. all of these
e. none of these
82. Karyotyping is usually done using what kind of cells?
a. muscle
b. sex
c. cartilage
d. blood
e. epidermal
83. Which chemical is used to keep chromosomes from separating during metaphase?
a. Giemsa stain
b. acetone
c. colchicine
d. alcohol
e. formaldehyde
84. Sex chromosomes
a. determine sex.
b. vary number and kind from one sex to another.
c. carry some genes that have nothing to do with sex.
d. were unknown to Mendel.
e. all of these
85. Which of the following designates a normal human female?
a. XXY
b. XY
c. XX
d. XYY
e. XO
86. In his experiments with Drosophila melanogaster, Morgan demonstrated that
a. fertilized eggs have two sets of chromosomes, but eggs and sperms have only one set in each gamete.
b. aneuploidy exists in karyotypes that have undergone deletions and inversions in specific chromosomes.
c. colchicine is effective in producing polyploidy in several generations.
d. certain genes are located only on an X chromosome and have no corresponding alleles on the Y chromosome.
e. all of these
87. All of the genes located on a given chromosome comprise a
a. karyotype.
b. bridging cross.
c. wild-type allele.
d. linkage group.
e. none of these
88. If two genes are on the same chromosome,
a. they are in the same linkage group
b. they assort independently.
c. crossing over occurs frequently.
d. they are segregated during meiosis.
e. an inversion will usually occur.
89. If two genes are almost always found in the same gamete, they are
a. located on non-homologous chromosomes.
b. located close together on the same chromosome.
c. located far apart on the same chromosome.
d. found on the sex chromosome.
90. If the paternal chromosome has alleles L, M, and n and the maternal chromosomes have l, m, and N, then the chromosome that cannot be produced by crossing over is
a. LMN
b. LmN
c. LMn
d. Lmn
e. lmn
91. In a pedigree chart a male showing the specific trait being studied is indicated by a
a. clear triangle.
b. clear square.
c. darkened diamond.
d. darkened square.
e. darkened circle.
92. Galactosemia
a. is an X-linked recessive trait expressed more commonly in males.
b. occurs more frequently in some ethnic groups than others.
c. is an autosomal recessive inheritance.
d. must be homozygous to be expressed.
e. b, c and d but not a.
93. A colorblind man and a woman with normal vision whose father was colorblind have a son. Colorblindness, in this case, is caused by an X-linked recessive gene. If only the male offspring are considered, the probability that their son is colorblind is
a. .25 (or 25 percent).
b. .50 (or 50 percent).
c. .75 (or 75 percent).
d. 1.00 (or 100 percent).
e. none of these
94. If a daughter expresses an X-linked recessive gene, she inherited the trait from
a. her mother.
b. her father.
c. both parents.
d. neither parent.
e. her grandmother.
95. An X-linked carrier is a
a. homozygous dominant female.
b. heterozygous female.
c. homozygous recessive female.
d. homozygous male.
e. heterozygous male.
96. A human X-linked gene is
a. found only in males.
b. more frequently expressed in females.
c. found on the Y chromosome.
d. transmitted from father to son.
e. found on the X chromosome.
97. A chromosome that has been broken and rejoined in a reversal sequence has undergone
a. inversion.
b. deletion.
c. duplication.
d. translocation.
e. crossing over.
98. Diploid organisms
a. have corresponding alleles on homologous chromosomes.
b. are usually the result of the fusion of two haploid gametes.
c. have two sets of chromosomes.
d. have pairs of homologous chromosomes.
e. all of these
99. For Mendel's explanation of inheritance to be correct,
a. the genes for the traits he studied had to be located on the same chromosome.
b. which gametes combine at fertilization had to be due to chance.
c. genes could not be transmitted independently of each other.
d. only diploid organisms would demonstrate inheritance patterns.
e. none of these