Download Exam 2 Spring 2007 and key

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Bio 309F
Examination #2
March 29, 2007
Name________________________________________________
Note: please place your name, course unique number (49790, 49795, 49800, 49805, 49810), and
bubble in your answers on the scantron. We will only grade the scantron so double check to be sure the
answers on the scantron are as you want them. Through out the exam, please cover your answers. Do
not use electronic gadgets, including telephone--so, please turn off your telephone prior to starting the
exam. Turn in both the scantron and the exam. CHOOSE THE BEST ANSWER
I. Multiple Choice (2 points each, 100 points total)
1. The absence of a Y chromosome in an early embryo causes:
A. the embryonic testis to become an ovary
B. the Wolffian duct system to develop
C. the Mullerian duct system to degenerate
D. the indifferent gonad to become an ovary
E. the indifferent gonad to become a testis
2. Which of the following can cause an XY individual to look like a female?
A. a mutation causing loss of the gene determining maleness
B. a mutation leading to non-functional testosterone
C. a mutation leading to non-functional testosterone receptor
D. A and B are correct
E. A, B, and C are correct
3. The chromosome complement of an individual with testicular feminization will be:
A. 22 autosomes + XX
E. 23 autosomes
B. 22 autosomes + XY
C. 21 autosomes + XX
D. 21 autosomes + XY
4. What term is used to describe individuals who are phenotypically female at birth but at puberty
become phenotypically males?
A. hermaphrodites
B. androgen insensitivity
C. estrogen insensitivity
D. pseudohermaphrodites
E. none of the above
5. A gene called ____ on the ____ chromosome causes the indifferent gonad to develop into a testis
A. PAR1 gene on the Y chromosome
B. AZF gene on the X chromosome
C. SRY gene on the Y chromosome
D. MSY gene on the Y chromosome
E. KCC gene on the X chromosome
6. External development for maleness is determined by
A. dihydroxytestosterone
B. testosterone
C. testosterone receptor
D. A and B are correct
E. A, B, and C are correct
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7. Although rare, individuals who are XX can be males and XY individuals can be females. Why?
A. an X chromosome of XX males has a male determining gene from Y chromosome
B. a male determining gene in the Y chromosome is deleted in XY females
C. XX males and XY females are due to hormonal differences
D. A and B are correct
E. A, B and C are correct
8. Loci that produce a phenotype in only one sex is referred to as:
A. sex-linked
B. sex-influenced
C. sex-limited
D. sex-defined
E. none of the above
9. Pattern baldness in humans is an example of:
A. sex-linked genes
B. sex-limited genes
C. sex-influenced genes
D. sex-defining gene
E. none of the above
10. One of the rules about the A,G,T,C base composition of DNA is:
A. the amount of A equals the amount of C
B. there is a 2:1 relationship between purines and pyrimidines
C. the amount of A equals the amount of G
D. there is a 1:1 relationship between A and T, and a 1:1 ratio between G and C
E. there is a 1:1 relationship between A and C, and a 1:1 ratio between G and T
11. The Watson/Crick DNA molecule is composed of:
A. a single polynucleotide chain, 4 bases (ATGC) and deoxyribose sugar
B. two polynucleotide chains, 4 bases (ATGC), phosphate, and deoxyribose sugar
C. two polynucleotide chains, 4 bases (AUGC), phosphate, and ribose sugar
D. three polynucleotide chains, 4 bases (ATGC), phosphate, and deoxyribose sugar
E. three polynucleotide chains, 4 bases (ATGC), phosphate, and ribose sugar
12. Genetic "blue print of life" requires which of the following characteristics?
A. the ability to replicate
B. the capacity for information storage
C. the capacity for expression of information
D. the ability to mutate
E. all of the above
13. The specificity (function) of a protein is determined by:
A. the interaction of amino acids with carbohydrate groups
B. the interaction of amino acids with lipid groups
C. the amino acid sequence
D. the number of amino acids
E. the over all type of amino acids present
14. In comparing the number of genes in the human genome to the number of proteins produced in
humans, the number of proteins are:
A. 10 times greater than the number of genes
B. the same as the number of genes
C. less than the number of genes
D. 20 times greater than the number of genes
E. 50 times higher than the number of genes
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15. What percentage of the human genome codes for proteins?
A. 0.5%
B. less than 5%
C. 5-8%
D. approximately 12%
E. approximately 20%
16. Watson and Crick received the Nobel Prize for:
A. generating x-ray crystallographic data of DNA structure
B. establishing that DNA replication is semiconservative
C. solving the structure of DNA
D. proving that DNA is the genetic material
E. showing how mutations could occur
17. RNA differs from DNA in the following way(s)
A. number of chains
B. sugar used
C. function
D. A and B are correct
E. A, B, and C are correct
18. The terms exons and introns refer to:
A. non-coding and coding sequences, respectively
B. coding and non-coding sequences, respectively
C. only junk DNA
D. G:C rich regions versus non G:C rich regions
E. A:T rich regions versus non A:T rich regions
19. One can synthesize a protein in a test tube containing all enzymes needed + nucleotides from a cat,
mRNA from a dog, and amino acids from a plant, tRNA from a human and rRNA from a horse. Which
protein would be made?
A. cat
D. human
B. dog
E. horse
C. plant
20. The transfer of purified DNA from one bacterium to another is called
A. transduction
D. transgenic
B. transformation
E. transomatic
C. translocation
21. Which of the following data contributed substantially to the understanding of the structure of DNA
A. a 1:1 ratio for A:T as well as G:C
B. the carbohydrate in DNA is deoxyribose
C. x-ray diffraction pattern obtained by examining crystalline DNA
D. A and B are correct
E. A and C are correct
22. What is the function of DNA polymerase?
A. it degrades DNA in cells
B. it adds RNA nucleotides to a new strand
C. it coils DNA round histones to form chromosomes
D. it adds DNA nucleotides to a replicating strand
E. none of the above
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23. A specific tRNA has binding sites for
A. anticodon and cytosine
B. anticodon and argenine
C. codon and specific amino acid
D. codon and specific base nucleotide
E. none of the above
24. Processing of pre-message RNA into mature message RNA (mRNA) involves
A. removal of introns
B. removal of exons
C. addition of poly A tail
D. A and C are correct
E. B and C are correct
25. The process of producing a polypeptide chain from mRNA is called
A. transformation
B. translation
C. transcription
D. transduction
E. none of the above
26. The inability to convert phenylalanine to tyrosine results in a genetic disorder called
A. PTU
B. PTI
C. PKU
D. PRT
E. PIT
27. The severity of the genetic disorder in question #26 can be minimized by
A. genetic engineering
D. blood transfusions
B. proper nutrition
E. none of the above
C. drug treatment
28. High fructose intolerance is a heritable trait with a genetic defect in metabolism and can be detected.
A. at birth with problems utilizing mother's milk
B. after birth when given solid foods such as apple sauce
C. after birth when given solid foods such as proteins
D. A and B are correct
E. A and C are correct
29. Which metabolic disease is inherited as a sex-linked recessive trait?
A. maple syrup syndrome
B. lactose intolerance
C. lesch-nyhan syndrome
D. Tay Sachs
E. PKU
30. Children born to homozygous PKU women who don’t modify their diet during pregnancy
A. will have normal mental capacity
B. will be mentally retarded
C. will have high levels of phenylalanine in their blood at birth
D. A and C are correct
E. B and C are correct
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31. Enzymes have all of the following characteristics except:
A. they act as biological catalysts
B. they are proteins
C. they carry out random chemical reactions
D. they convert substrates into products
E. they can be involved in genetic disease
32. A frameshift mutation causes
A. a nucleotide substitution
B. a three base insertion
C. a three base deletion
D. the same amino acid sequence to be produced after the mutation
E. a different amino acid sequence to be produced after the mutation
33. Which of the following contribute to defects in collagen
A. defect in enzyme that cuts pro-collagen into collagen
B. defect or absence of alpha-2 polypeptide chain
C. defect or absence of muscle protein to interact with collagen
D. A and B are correct
E. A, B, and C are correct
34. Fragile-X Syndrome is the result of
A. point mutation
B. rearrangement of base nucleotides
C. frame shift mutation
D. deletion of base nucleotides
E. multiple repeat of triplicate base nucleotides
35. The Bruce Ames phenylketonuria test measures levels of ________ in blood from newborns
A. lipids to diagnose Tay-Sachs disease
B. metabolites of controlled substances
C. phenylalanine
D. chemically altered nucleotides
E. chemically altered carbohydrates
36. The Bruce Ames test for detection of chemical mutagens utilizes
A. a mutant strain of bacteria that requires tyrosine to grow
B. a mutant strain of bacteria that requires phenylalanine to grow
C. a mutant strain of bacteria that requires alanine to grow
D. a mutant strain of bacteria that requires histidine to grow
E. a mutant strain of bacteria that requires valine to grow
37. A problem in using bacteria to detect mutagens is
A. non-mutated alleles interfer with observing mutated alleles
B. have an extremely high spontaneous mutation rate
C. do not have enzyme system (liver) for processing chemicals
D time consuming and expensive
E. assay is technically difficult
38. Problems in using human somatic cells in culture to detect mutagens include
A. non-mutated alleles interfer with observing recessive mutated alleles
B. have an extremely high spontaneous mutation rate
C. do not have enzyme system (liver) for processing chemicals
D. A and C are correct
E. A and B are correct
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39. Ultraviolet light (UV) causes
A. thymine dimers
B. adenine dimers
C. guanine dimers
D. cytosine dimers
E. uracil dimers
40. Which genetic disorder results from a defect in DNA repair mechanisms?
A. Lesch-Nyhan
B. Tay-Sachs
C. PKU
D. xeroderma pigmentosum
E. cystic fibrosis
41. A missense mutation in a gene with 2,100 base pairs of DNA code for a protein with ___ amino
acids
A. 699
B. 700
C. 701
D. 1,400
E. 1,399
42. _____ is a genetic disorder that becomes increasing severe in successive generations
A. cystic fibrosis
B. sickle cell anemia
C. myotonic dystrophy
D. Down's syndrome
E. maple syrup syndrome
43. Which of the following chemical(s) is a known mutagen?
A. benzo (A) pyrene
B. caffeine
C. aspartane (NutraSweet)
D. A and B are correct
E. A and C are correct
44. Mutation that deletes a termination codon will result in the transcription/translation of a protein that
A. is most likely non-functional
B. that is longer in size
C that is shorter in size
D. A and B are correct
E. A and D are correct
45. A mutation that adds a termination codon to the center of a gene will result in the
transcription/translation of a protein that
A. is most likely non-functional
B. that is longer in size
C that is shorter in size
D. A and C are correct
E. A and D are correct
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46. A couple's newborn had a normal embryonic/fetal development but was determined to be anemic at
one year of age. Sickle cell anemia was not involved. The most likely cause for the anemia is a
defective hemoglobin chain. Which chain?
A. alpha chain
B. beta chain
C. gamma chain
D. epsilon chain
E. hg chain
47. H. J. Muller received the Nobel prize for work conducted on this campus, showing that ionizing
radiation
A. induces chromosome breaks in human germinal cells
B. induces chromosome breaks in human somatic cells
C. induces mutations in enzymes regulating metabolic pathways in fungi called Neurospora
D. induces lethal mutations in Drosophilia
E. none of the above
48. A base nucleotide substitution mutation in an intron would result in:
A. mutant protein
D. normal protein
B. reduced size protein
E. non-functional protein
C. increased size protein
49. Which of the following is/are involved in repairing UV-induced damage to DNA?
A. excision repair enzyme cuts DNA and removes damaged DNA
B. DNA polymerase creates new sequence
C. DNA ligase seals the polynucleotide chain
D. A and B are correct
E. A, B, and C are correct
50. A Prion is a protein that
A. assumes both stable and infectious conformations
B. can be inherited
C. can be acquired
D. is resistant to destruction by proteases
E. all are correct