Name: _________________________________________ Chapter 12 Practice Test (page 1)

1. _______________________________ When genetic material from the environment Changes the genetic structure inside bacteria

2. _______________________________ A virus that infects and kills a bacteria

3. _______________________________ Basic unit of DNA structure

4. _______________________________ any of a group of basic proteins in chromatin

5. _______________________________ Enzyme that “unzips” double-stranded DNA

6. _______________________________ DNA region that initiates transcription of a gene

7. _______________________________ sequence of DNA that does not code for proteins

8. _______________________________ sequence of three nucleotides that form a unit of genetic code in DNA or messenger RNA.

9. _______________________________ sequence of three nucleotides that form a unit

of genetic code in transfer RNA.

10. _______________________________ condition in which an organism has extra sets of Chromosomes

11. _______________________________ groups of genes operating together

12. _______________________________ genes that control cell differentiation during Development

13. ______________________________ The order of nitrogenous bases in DNA determines

the order of __________ in proteins.

14. ______________________________ The lac repressor releases the operator in the presence of __________.

Name: _________________________________________ Chapter 12 Practice Test (page 2)

15. Draw the basic structure of a nucleotide with its three parts.

16. Write the complementary sequence to the following DNA strand A A T T C G C C G G T A T T A G A C G T T

17. Circle a nucleotide Label the sugar Label the phosphate Label the bases that are not

already labeled

18. According to the figure (wheel of base codes), what codons specify the amino acid arginine?

Name: _________________________________________ Chapter 12 Practice Test (page 3)

19. What is this diagram showing? __________________________________

20. A _______________________________

21. B. ______________________________

22. C. ______________________________

23. D. ______________________________

24. E. ______________________________

25. F. ______________________________

26. G. ______________________________

27. What general type of mutations results from A?

A. __________________________

B. __________________________

C. __________________________

D. __________________________

28. In the figure, which process or processes involve two chromosomes? ________________________________________________________

Name: _________________________________________ Chapter 12 Practice Test (page 4)

29. __________ What did Griffith observe when he injected into mice a mixture of heat-killed disease-causing bacteria and live harmless bacteria? a. The disease-causing bacteria changed into harmless bacteria. b. The mice developed pneumonia. c. The harmless bacteria died. d. The mice were unaffected

30. __________ Which of the following is a nucleotide found in DNA?

a. Ribose + phosphate group + thymine b. Ribose + phosphate group + uracil c. Deoxyribose + phosphate group + uracil d. Deoxyribose + phosphate group + cytosine

31. __________ DNA replication results in two DNA molecules,

a. Each with two new strands b. One with two new strands and the other with two original strands c. Each with one new strand and one original strand d. Each with two original strands.

32. __________ During mitosis, the

a. DNA molecules unwind b. Histones and DNA molecules separate c. DNA molecules become more tightly coiled d. Nucleosomes become less tightly packed

33. __________ Unlike DNA, RNA contains

a. Adenine c. phosphate groups b. Uracil d. thymine

34. __________ Which type(s) of RNA is(are) involved in protein synthesis?

a. Transfer RNA only b. Messenger RNA only c. Ribosomal RNA and transfer RNA only d. Messenger RNA, ribosomal RNA, and transfer RNA

35. __________ During transcription, an RNA molecule is formed

a. That is complementary to both strands of DNA b. That is complementary to neither strand of DNa c. That is double-stranded d. Inside the nucleus

Name: _________________________________________ Chapter 12 Practice Test (page5 )

36. __________ How many codons are needed to specify three amino acids? a. 3 c. 9 b. 6 d. 12

37. __________ Which of the following terms is LEAST closely related to the others?

a. Intron c. polypeptide b. tRNA d. anticodon

38. __________ Which of the following is NOT a gene mutation?

a. Inversion c. deletion b. Insertion d. substitution

39. __________ Which of the following statements is true?

a. A promoter determines whether a gene is expressed. b. An expressed gene is turned off. c. Proteins that bind to regulatory sites on DNA determine whether a gene is

expressed. d. RNA polymerase regulates gene expression.

40. __________ A lac repressor turns off the lac genes by binding to

a. The promoter b. tRNA c. the operator d. the lac genes

41. __________ Gene regulation in eukaryotes

a. usually involves operons b. is simpler than in prokaryotes c. allows for cell specialization d. includes the action of DNA polymerase.

42. __________ Which of the following statements is NOT true?

a. Mutations do not occur in hox genes. b. Hox genes that are found in different animals are very different from each other c. Hox genes control the normal development of an animal d. Hox genes occur in clusters

Name: _________________________________________ Chapter 12 Practice Test (page 6)

43. __________ Avery’s experiments showed that bacteria are transformed by a. RNA c. proteins b. DNA d. carbohydrates

44. __________ DNA is copied during a process called

a. Replication c. transcription b. Translation d. transformation

45. __________ In eukaryotes, DNA

a. Is located in the nucleus c. Is located in the ribosomes b. Floats freely in the cytoplasm d. Is circular

46. __________ RNA contains the sugar

a. Ribose c. glucose b. Deoxyribose d. lactose

47. __________ Which RNA molecule carries amino acids?

a. Messenger RNA c. ribosomal RNA b. Transfer RNA d. RNA polymerase

48. __________ What is produced during transcription?

a. RNA molecules b. DNA molecules c. RNA polymerase d. Proteins

49. __________ What happens during the process of translation?

a. Messenger RNA is made from DNA b. The cell uses information from messenger RNA to produce proteins c. Transfer RNA is made from messenger RNA d. Copies of DNA molecules are made.

50. __________ Genes contain instructions for assembling

a. Purines c. proteins b. Nucleosomes d. pyrimidines

51. __________ A mutation that involves a single nucleotide is called a(an)

a. Chromosomal mutation c. point mutation b. Inversion d. translocation

Name: _________________________________________ Chapter 12 Practice Test (page 7)

52. __________ A promoter is a a. Binding site for DNA polymerase b. Binding site for RNA polymerase c. Start signal for transcription d. Stop signal for transcription

53. __________ In E. coli, the lac operon controls the

a. Breakdown of lactose b. Productions of lactose c. Breakdown of glucose d. Production of glucose

54. __________ Which of the following is NOT generally part of a eukaryotic gene? a. Operon c. promoter sequences b. TATA box d. enhancer sequences

55. __________ Hox genes determine an animal’s

a. Basic body plan c. skin color b. Size d. eye color

56. What happens to lac repressors in E. coli when lactose is present?

57. What is the relationship between codons and anticodons? How is this relationship important?

Name: _________________________________________ Chapter 12 Practice Test (page 8)

58. Contrast the functions of the three main types of RNA.

59. Mendel might have been surprised to learn that gene simply contain the instructions for

assembling proteins. What do proteins have to do with the phenotype of an organism?

60. Why do some kinds of point mutations cause greater changes in proteins than others?

61. What causes translation to stop?

Biology Chapter 12 Practice Test Key

1. Transformation 2. Bacteriophage 3. Nucleotide 4. Histone 5. DNA polymerase 6. Promoter 7. Intron 8. Codon 9. Anticodon 10. Polyploidy 11. Operon 12. Hox genes 13. Amino acids 14. Lactic acid 15. SEE BOOK 16. T. T A. A. G. C. G. G. C. C. A T A. A. T. C. T. G. C. A. A. 17. The sugar is the white pentagon, the phosphate is the black circle, the bases are in the

middle. Each A should pair with T and each C should pair with G 18. AGG, AGA, CGA, CGC, CGU, CGG 19. The production of protein through transcription and translation 20. Nucleus 21. Messenger RNA (mRNA) 22. ribosome 23. Transfer RNA (tRNA) 24. Anticodon 25. codon 26. amino acid 27. A. deletion

B. duplication C. a segment becomes oriented in the reverse direction D. translocation

28. Process D 29. B. the mice developed pneumonia 30. D. deoxyribose + phosphate group + cytosine 31. C. each with one new strand and one original strand 32. A. DNA molecules unwind 33. B. uracil 34. D. messenger RNA, ribosomal RNA, and transfer RNA 35. D. inside the nucleus 36. C. 9 37. A. Intron 38. A. inversion

39. C. proteins that bind to regulatory sites on DNA determine whether a gene is expressed 40. C. the operator 41. C. allows for cell specialization 42. B. Hox genes that are found in different animals are very different from each other 43. B. 44. A. replication 45. A. is located in the nucleus 46. A. ribose 47. B. transfer RNA 48. A. RNA molecules 49. B. The cell uses information from messenger RNA to produce proteins. 50. C. proteins 51. C. point mutation 52. B. binding site for RNA polymerase 53. A. breakdown of lactose 54. A. operon 55. A. basic body plan 56. lactose binds to the lac repressor, causing the repressor to release the operator. 57. the codons and anticodons have complementary nitrogenous bases, allowing them to

base pair. Since each tRNA carries only one kind of amino acid, the base pairing between the anticodons and codons brings a specific sequence of amino acids to the ribosomes.

58. Messenger RNA carries copies of instructions for assembling proteins from DNA to the ribosomes. Ribosomal RNA is a component of the ribosomes. Transfer RNA carries amino acids to the ribosomes for assembly into proteins. 59. Proteins have many different functions in an organism. These functions include catalyzing and regulating chemical reactions, regulating growth patterns, and providing

the actual structural components of the organisms. Together these functions play a key role in producing an organism’s traits, or phenotype.

60. Point mutations include substitutions, insertions, and deletions of single nucleotides in

DNA. Insertions and deletions have a greater effect on proteins than do substitutions because insertions and deletions change the reading frame of the genetic code, affecting every amino acid that follows the point of mutation. In contrast, a substitution affects a single amino acid. A change in more than one amino acid is more likely to alter the function of the protein than is a change in the single amino acid.

61. A stop codon on the mRNA causes translation to stop.