Q. No.The backbone of a polynucleotide chain is made of:
| 1. | Sugar and nitrogenous bases |
| 2. | Phosphate and nitrogenous bases |
| 3. | Sugar and phosphate |
| 4. | Sugar, phosphate, and nitrogenous bases |
Subtopic: The DNA | DNA Double Helix |
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Level 1: 80%+
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Deoxythymidine is:
| 1. | a substituted pyrimidine found only in DNA |
| 2. | a nucleoside monophosphate found only in DNA |
| 3. | a nucleoside found in DNA |
| 4. | a nucleotide formed by chemical modifications in a RNA nucleotide |
Subtopic: DNA Double Helix |
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Level 3: 35%-60%
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What would not be true for the structure of a polynucleotide chain?
| 1. | 5’-end of polynucleotide chain has a free phosphate moiety at 5'-end of sugar. |
| 2. | 3’-end of polynucleotide chain has a free OH group 3'-C of sugar. |
| 3. | The backbone of a polynucleotide chain is formed due to sugar and phosphates. |
| 4. | The nitrogenous bases linked to phosphate moiety project from the backbone. |
Subtopic: DNA Double Helix |
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Level 2: 60%+
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Subtopic: DNA Double Helix |
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Level 1: 80%+
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In 1953, James Watson and Francis Crick, proposed a very simple but famous Double Helix model for the structure of DNA, based on the X-ray diffraction data produced by:
| 1. | Maurice Wilkins and Rosalind Franklin |
| 2. | Beadle and Tatum |
| 3. | Temin and Baltimore |
| 4. | Avery–MacLeod–McCarty |
Subtopic: DNA Double Helix |
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According to Erwin Chargaff, in a double-stranded DNA
| 1. | The ratios between Adenine and Thymine, and, Guanine and Cytosine are constant and equal. |
| 2. | The ratios between Adenine and Thymine, and, Guanine and Cytosine are constant but are not equal to one. |
| 3. | The ratios between Adenine and Guanine, and, Thymine and Cytosine are constant and equal. |
| 4. | The ratios between Adenine and Guanine, and, Thymine and Cytosine are constant but are not equal to one. |
Subtopic: DNA Double Helix |
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Level 2: 60%+
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“For a double stranded DNA, the ratios between Adenine and Thymine and Guanine and Cytosine are constant and equals one” – this statement is known as:
1. Central dogma of molecular biology
2. Chargaff’s rule
3. Tetra-nucelotide hypothesis by Levene
4. Genetic equilibrium
1. Central dogma of molecular biology
2. Chargaff’s rule
3. Tetra-nucelotide hypothesis by Levene
4. Genetic equilibrium
Subtopic: DNA Double Helix |
95%
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The base pairing in a double stranded DNA is correctly described as:
| 1. | Similar | 2. | Identical |
| 3. | Complementary | 4. | Synergistic |
Subtopic: DNA Double Helix |
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Level 1: 80%+
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If each strand of a dsDNA acts as a template for a new strand, the two daughter DNAs will be:
| 1. | Complementary to each other |
| 2. | Identical to the parental DNA |
| 3. | Similar to each other |
| 4. | Complementary to the parental DNA |
Subtopic: DNA Double Helix |
Level 3: 35%-60%
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Which of the following is not a feature of the double helix model of DNA?
| 1. | The two chains have anti-parallel polarity |
| 2. | A purine always comes opposite to a pyrimidine |
| 3. | The pitch of the DNA is 3.4 nm |
| 4. | The two chains are coiled in a left handed fashion |
Subtopic: DNA Double Helix |
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Level 1: 80%+
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