Alfred Hershey and Martha Chase made a big contribution in proving DNA role as the hereditary molecule. The experiment is shown in the diagram. A and C are the presence or absence of radioactivity detected in cells B and D are the presence or absence of radioactivity detected in supernatants cells. Identify A, B, C and D:

1. A - No Radioactivity (35S) detected in cells; B - Radioactivity (32P) detected in supernatant; C - Radioactivity (35S) detected in cells; D - No Radioactivity in supernatant

2. A- Radioactivity (35S) detected in cells; B - No Radioactivity (35S) detected in supernatant; C - Radioactivity (32P) detected in cells; D - No Radioactivity in supernatant

3. A - No Radioactivity (35S) detected in cells; B - Radioactivity (35S) detected in supernatant; C - Radioactivity (32P) detected in cells; D - No Radioactivity in supernatant

4. A - No Radioactivity (35S) detected in cells; B - Radioactivity (35S) detected in supernatant; C - No Radioactivity (32P) detected in cells; D - Radioactivity in supernatant

If the DNA of this virus was labeled with 32P and the protein of the virus was labeled with 35S, which molecule(s) would be present inside the cells?

1. 35S and 32P

2. 35S only

3. 32P only

4. Neither molecule would be present inside the cell

The prediction of sequence of amino acid is _____A ____ if the sequence of nucleotides mRNA is known. The prediction of sequence of nucleotide in concerned mRNA is ____B____ because the genetic code is _____C_____:

1. A - possible, B - impossible, C - universal

2. A - possible, B - impossible, C - degenerate

3. A - impossible, B - possible, C - universal

4. A - impossible, B - possible, C - degenerate

Choose the correct statements:

I. Binding of mRNA to the ribosome is loose and reversible.

II. The ribosome, which is composed of tRNA and proteins, consists of a small and large subunit.

III. Each of the 20 amino acids has a minimum of one specific tRNA molecule.

IV. tRNAMET binds to the first codon (AUG) - this is called the START codon.

V. The second tRNA binds to the second codon so that their attached monosaccharides are next to each other

VI. The newly formed polypeptide may undergo post-transcriptional modification.

1. I, III and IV         

2. II, IV, VI               

3. II, V and VI           

4. I, V, VI

If a length of DNA has 45,000 base pairs, how many complete turns will the DNA molecule take?

1. 45000  

2. 450                

3. 4500               

4. 45

Go through the following facts:

I. 'AAG' always code for lysine. It cannot code for any other amino acid.

II. Serine amino acid can be coded by UCU / UCC / UCA or UCG.

III. UUU from phenylalanine in bacteria as well as human beings.

IV. UUU GGG CCC AAA Me codes for five amino acids.

Now point out nature of genetic code after reading above:

1. I – Specificity / Non-ambiguity of code; II - Universality of code; III - Degeneracy of code; IV - Triplet and non-overlapping code

2. I – Specificity / Non-ambiguity of code; II - Degeneracy of code; III - Universality of code; IV - Triplet and non-overlapping code

3. I – Specificity / Non-ambiguity of code; II - Degeneracy of code; III - Universality of code; IV - Triplet and overlapping code

4. I – Specificity / Non-ambiguity of code; II - Universality of code; III - Degeneracy of code; IV - Triplet and overlapping code

The full form of ELSI is:

1. Embedded Low Software Index    

2. Ear Lung Spleen Immunity

3. Ethical Legal and Social Issue      

4. Endonuclease Ligase Surface Immunity

The force that holds DNA together in a double helix is:

1. The force of the twist                   

2. Covalent bonds

3. Ionic bonds or ionic interactions   

4. Hydrogen bonds

Experiments by Avery, Macleod, and McCarty supported DNA as the genetic material by showing that:

1. Both protein and DNA samples provided the transforming factor

2. DNA was not complex enough to be the genetic material

3. Only samples with DNA provided transforming activity

4. Even though DNA was molecularly simple, it provided adequate variation to act as the genetic material

What are the mini-satellites?

1. r-DNA             

2. VNTR              

3. c-DNA             

4. SAT