Download A - sandsbiochem

Name: __________________________________
Chapter 12 Review Sheet
A. Multiple Choice: Circle the letter of the answer that best fits the statement or question below.
1. How many bases make up the human genome?
a. three million
c. three hundred thousand
b. six million
d. three billion
2. What percent of DNA codes for traits?
a. 1%
b. 15%
c. 50%
d. 100%
3. The shape of DNA is:
a. straight
b. circular
c. flat
d. spiral
4. DNA is located within which part of the cell?
a. cytoplasm
b. nucleus
c. vacuole
d. cell membrane
5. How many chromosomes do humans have?
a. 2
b. 4
c. 23 pairs
d. 46 pairs
Mrs. Sands
6. Genes contain the instructions to make which macromolecule?
a. Nucleic acids
c. Carbohydrates
b. Proteins
d. Lipids
7. Approximately how many genes do humans have?
a. 10,000
c. 30,000
b. 50,000
d. 1 million
8. Which of the following correctly describes the structure of a nucleotide?
a. amino acid, sugar, base
c. phosphate, lipid, carbohydrate
b. protein, phosphate, base
d. sugar, phosphate, base
9. The sides or backbone of the DNA molecule are made up of:
a. phosphate and sugar
c. sugar
b. chemical bases
d. amino acids
10. What type of bond holds nitrogen bases together in the DNA double helix?
a. covalent
c. hydrogen
b. ionic
d. nuclear
11. How many strands is DNA?
a. 1
b. 2
c. 3
d. 4
12. In DNA what chemical base does adenine (A) bond with?
a. Guanine (G)
c. Thymine (T)
b. Cytosine (C)
d. Adenine (A)
13. In DNA what chemical base does Cytosine (C) bond with?
a. Guanine (G)
c. Thymine (T)
b. Cytosine (C)
d. Adenine (A)
14. Which of the following statements best describes a DNA molecule?
a. It is a double helix.
c. It is composed of amino acids.
b. It contains the sugar ribose.
d. It contains the nitrogenous base uracil
1
15. A portion of one strand of a DNA molecule is  ACCTGAAGG. Assuming there are no mutations in this portion of
the DNA, what is the corresponding sequence on the complementary DNA strand?
a.) ACCTGAAGG
c.)TGGACTTCC
b.) GTTCAGGAA
d.) UGGACUUCC
16. Which scientist(s) performed the original experiment on mice and discovered that bacteria are able to take up foreign
DNA.
a. Avery
c. Griffith
b. Watson & Crick
d. Hershey & Chase
17. Watson and Crick build models that demonstrate that:
a. DNA and RNA have the same structure.
b. the DNA helix is held together by hydrogen bonds.
c. guanine forms hydrogen bonds with adenine.
d. thymine forms hydrogen bonds with cytosine.
18. Chargaff’s rules, or the base-pairing rules, state that in DNA:
a. the amount of adenine equals the amount of thymine.
b. the amount of guanine equals the amount of cytosine.
c. the amount of guanine equals the amount of thymine.
d. Both a and b
19. Which enzyme unzips and breaks the hydrogen bonds during DNA replication?
a. Helicase
c. Nucleotase
b. RNA polymerase
d. DNA polymerase
20. In RNA what chemical base does adenine (A) bond with?
a. Guanine (G)
c. Thymine (T)
b. Cytosine (C)
d. Uracil (U)
21. The enzyme responsible for adding nucleotides to the DNA template during DNA replication is:
a. replicase
c. helicase
b. DNA polymerase.
d. nucleotidase
22. In order for protein synthesis to occur, mRNA must travel to which organelle:
a. centrioles.
c. ribosomes.
b. nucleus.
d. cell membrane.
23. In RNA molecules uracil replaces which base:
a. thymine
b. guanine
c. adenine
d. cytosine
24. What enzyme is responsible for unwinding the DNA and adding mRNA nucleotides during transcription?
a. helicase
c. RNA polymerase
b. DNA polymerase.
d. nucleotidase
25. During translation:
a. DNA is replicated.
b. mRNA is produced.
c. proteins are synthesized.
d. transcription occurs.
Use the following mRNA strand to answer questions #26 and #27  mRNA molecule: CUC AAG UGC
26. Which of the following would represent the strand of DNA from which the mRNA strand was made?
a. CUC AAG UGC
c. GAG UUC ACG
b. GAG TTC ACG
d. AGA CCT GTA
27. Which of the following would represent the strand of tRNA anticodons that would base pair with the mRNA codons?
a. CUU CGU GAA
c. CUC GAA CGU
b. GAG TTC ACG
d. GAG UUC ACG
2
28. Which of the following statements best describes a DNA molecule?
a. It is a double helix.
c. It contains the sugar ribose.
b. It is composed of amino acids.
d. It contains the nitrogenous base uracil.
29. Individuals with one form of lactose intolerance do not produce the enzyme lactase because the gene coding for the
production of lactase is shut off in their cells. This means that which of the following processes does not occur for the
gene?
a. Hydrogenation
c. replication
b. mutation
d. transcription
30. Fireflies produce light inside their bodies. The enzyme luciferase is involved in the reaction that produces the light.
Scientists have isolated the luciferase gene. A scientist inserts the luciferase gene into the DNA of cells from another
organism. If these cells produce light, the scientist knows that which of the following occurred?
a. The luciferase gene mutated inside the cells.
b. The luciferase gene was transcribed and translated.
c. The luciferase gene destroyed the original genes of the cells.
d. The luciferase gene moved from the nucleus to the endoplasmic reticulum.
31. A portion of one strand of a DNA molecule has the sequence: ACCTGAAGG. Assuming there are no mutations in
this portion of the DNA, what is the corresponding sequence on the complementary DNA strand?
a. ACCTGAAGG
c. TGGACTTCC
b. GTTCAGGAA
d. UGGACUUCC
32. During DNA replication, the wrong nucleotide was inserted in the DNA sequence. Which of the following terms
describes this situation?
a. mutation
c. transcription
b. regeneration
d. translation
33. In a molecule of double-stranded DNA, the amount of adenine present is always equal to the amount of:
a. cytosine.
c. thymine.
b. guanine.
d. uracil.
34. In a eukaryotic cell, which of the following processes directly involves DNA?
a. translation
c. cellular respiration
b. active transport of ions
d. replication of chromosomes
35. Which of the following statements best describes why the change in only one DNA base of the hemoglobin gene
results in a different protein product of the gene?
a. The change prevents mRNA from being made.
b. The change alters the amino acid sequence of the protein.
c. the change causes the blood cells to divide in an uncontrolled way.
d. The change creates a second strand of mRNA for each RNA molecule.
B. Labeling: Label the parts on the diagram below.
3
C. Matching:
TERM
DEFINITION
21. ______ DNA
a.) section of DNA that codes for a trait
22. ______Chromosomes
b.) Shape of DNA
23. ______Genes
c.) stores genetic information
24. ______Nucleotide
d.) chemical building blocks of DNA, made of phosphate, sugar and a base
25. ______Double Helix
e.) bundles of DNA
SCIENTIST
CONTRIBUTION
36. _____ Griffith
a. Identified components (parts) of DNA called nucleotides
37. _____ Mendel
b. Stated that DNA can change cell’s properties, supported Griffith’s conclusions
38. _____ Watson & Crick
c. Nicknamed “Father of Genetics;” used pea plants to study how traits are inherited
39. _____ Hershey & Chase
d. Determined rules for base pairing (A-T and C-G)
40. _____ Chargaff
e. Used radioactive material to label DNA & protein; infected bacteria passed on DNA;
helped prove that DNA is genetic material not proteins
41. _____ Avery
f. Used X-Ray diffraction to take pictures of DNA structure; discovered two forms of DNA
42. _____ Franklin & Wilkins
g. Credited with the discovery of the double helix structure of DNA, won Nobel prize
43. _____ Levene
h. Injected mice with pneumonia bacteria; discovered that living cells “transformed”
C. Short Answer: Answer all questions below.
44. Why we need to replicate (copy) our DNA?
45. What is the goal of transcription?
46. Why do we need to form mRNA during transcription?
47. Compare and contrast DNA and RNA. Give at least two ways DNA and RNA are similar and different.
48. What is the goal of translation?
mRNA Codon Table
49. Fill in the blanks below using the original DNA strand.
DNA
CGA TGG CAT
mRNA
___
___ ___
tRNA
___
___ ___
Amino Acid
____ ____ ____
4