Bio 181 Exam #4 UPDATED ACTUAL
Exam Questions and CORRECT Answers
Suppose you are provided with an actively dividing culture of E. Coli bacteria to which
radioactive thymine has been added. What would happen if a cell replicates once in the presence
of this radioactive base?
A. One of the daughter cells, but not the other, would have radioactive DNA
B. Neither of the two daughter cells would be radioactive
C. All four bases of the DNA would be radioactive
D. Radioactive Thymine would pair with nonradioactive guanine
E. DNA in both daughter cells would be radioactive. - CORRECT ANSWER - E. DNA in
both cells would be radioactive
- This is true because one strand comes from the parent, and the other is the newly replicated
one, meaning that both daughter cells will be radioactive.
The polymerization of DNA, a phosphodeister 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. Carbon 6
C. The 3' OH
D. a nitrogen form the nitrogen containing base - CORRECT ANSWER - C. The 3' OH
- This is true because the DNA Phosphodeister can only build upon the 3' end.
DNA contains the template needed to copy itself, but it has no cellular activity in cells. What
catalyzes the formation of phosphodeister between adjacent nucleotides in the DNA polymer
being formed?
A. topoisomerase
, B. DNA Ploymerase
C. ATP
D. deoxyribonucleotide triphosphates - CORRECT ANSWER - B. DNA polymerase
- this is true because it is the enzyme that catalyzes DNA Synthesis
Telomere shortening puts a limit on the number of times a cell can divide. Research has shown
that telomere can extend the life span of cultured human cells. How might adding telomerase
affect cellular aging?
A. Telomere will speed up the rate of cell proliferation
B. Telomerase eliminates telomere shortening and retards cellular aging
C. Telomerase shortens telomeres which delays cellular aging
D. Telomerase would have no effect on cellular aging. - CORRECT ANSWER - B.
Telomerase eliminates Teomere shortening and retards cellular aging.
Which of the following cells have reduced or very little active telomerase activity?
A . most normal somatic cells
B. most normal germ cells( progenitors of gametes)
C. Most Cancer Cells - CORRECT ANSWER - A. Most normal somatic cellss
What are the two major components of DNA strucutre? - CORRECT ANSWER - 1. A
backbone made up of sugar and phosphate groups of deoxyribonucleotides
2. A series of nitrogen containing bases that project from the backbone
What are the 4 nitrogen containing bases in DNA - CORRECT ANSWER - 1. Adenine(A)
2. Thymine(T)
3. Guanine(G)
4. Cytosine(C)
Exam Questions and CORRECT Answers
Suppose you are provided with an actively dividing culture of E. Coli bacteria to which
radioactive thymine has been added. What would happen if a cell replicates once in the presence
of this radioactive base?
A. One of the daughter cells, but not the other, would have radioactive DNA
B. Neither of the two daughter cells would be radioactive
C. All four bases of the DNA would be radioactive
D. Radioactive Thymine would pair with nonradioactive guanine
E. DNA in both daughter cells would be radioactive. - CORRECT ANSWER - E. DNA in
both cells would be radioactive
- This is true because one strand comes from the parent, and the other is the newly replicated
one, meaning that both daughter cells will be radioactive.
The polymerization of DNA, a phosphodeister 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. Carbon 6
C. The 3' OH
D. a nitrogen form the nitrogen containing base - CORRECT ANSWER - C. The 3' OH
- This is true because the DNA Phosphodeister can only build upon the 3' end.
DNA contains the template needed to copy itself, but it has no cellular activity in cells. What
catalyzes the formation of phosphodeister between adjacent nucleotides in the DNA polymer
being formed?
A. topoisomerase
, B. DNA Ploymerase
C. ATP
D. deoxyribonucleotide triphosphates - CORRECT ANSWER - B. DNA polymerase
- this is true because it is the enzyme that catalyzes DNA Synthesis
Telomere shortening puts a limit on the number of times a cell can divide. Research has shown
that telomere can extend the life span of cultured human cells. How might adding telomerase
affect cellular aging?
A. Telomere will speed up the rate of cell proliferation
B. Telomerase eliminates telomere shortening and retards cellular aging
C. Telomerase shortens telomeres which delays cellular aging
D. Telomerase would have no effect on cellular aging. - CORRECT ANSWER - B.
Telomerase eliminates Teomere shortening and retards cellular aging.
Which of the following cells have reduced or very little active telomerase activity?
A . most normal somatic cells
B. most normal germ cells( progenitors of gametes)
C. Most Cancer Cells - CORRECT ANSWER - A. Most normal somatic cellss
What are the two major components of DNA strucutre? - CORRECT ANSWER - 1. A
backbone made up of sugar and phosphate groups of deoxyribonucleotides
2. A series of nitrogen containing bases that project from the backbone
What are the 4 nitrogen containing bases in DNA - CORRECT ANSWER - 1. Adenine(A)
2. Thymine(T)
3. Guanine(G)
4. Cytosine(C)
