1If phages are labeled only with radioactive sulfur and allo

1.If phages are labeled only with radioactive sulfur and allowed to infect bacterial cells, the phage progeny resulting from lysis are expected

a. To have radioactive DNA and proteins

b. To have radioactive DNA

c.To have radioactive proteins

d. To have radioactive carbohydrates

e. To be non-radioactive

2. Franklin’s X-rays crystallography work provided which of the following regarding the structure of DNA?

a. It had a helical structure with more than one strand

b.Purines are paired with pyrimidines

c.It replicates in a semi-conservative manner

d. DNA is organized in a 5’ to 3’ direction

What types of amino acids are most responsible for binding of DNA to histones?

a.Hydrophobic amino acids

b. Polar amino acids

c.Positively charged amino acids

d.Negatively charged amino acids

Solution

Explanation: 1) The phages labeled with sulphur allowed to infect bacterial cells,the phage progeny resulting from the bacterial lysis are expected to be non-radioactive.

2)Franklins x-ray crystallography work proved DNA is a helical structure with more than one strand running on an axis.

3) DNA is negatively charged, where as histones are proteins with positive charge.So Positive charge amino acids of histone binds to the negative charge DNA. DNA was wrapped around octomer histone proteins(histone protein is termed as octomer as it contains 2 sets of H2A,H2B,H3 ans H4 proteins) to form an nucleosome of a chromatin of a chromosome.