In a DNA molecule, two polynucleotide chains are different in ________ .

Which carbon atom of deoxy Ribose sugar in $DNA$ does NOT contain the

bond?

A bacterial strain $\mathrm{S}$ was heat killed. Another strain $\mathrm{R}$ (living) was taken and mixed with this S strain. This mixture of $\mathrm{S}+\mathrm{R}$ strains were injected into mice. Which of the following are observed by Griffith?

I. The cells of $\mathrm{S}$ strain were dead in dead mice.

II. The bacterial cells without polysaccharide coat are transformed into virulent strain in the injected mice.

II. Griffith could not find living $\mathrm{S}$ strain in the body of dead mice.

IV. Griffith could find living $\mathrm{S}$ strain in the body of dead mice.

The correct combination is:

DNA molecule has length of $476 \stackrel{\circ }{\mathrm{A}}$ with $20\%$ guanosine. Choose the correct features of $\mathrm{DNA}$

$\mathrm{I})$ $56 \mathrm{CTP}$
$\mathrm{II})$ $336$ Hydrogen bonds
$\mathrm{III})$ Total $150$ nucleotides
$\mathrm{IV})$ $84 \mathrm{TTP}$

A student grew virus in three different media containing ${\mathrm{P}}^{32}, {\mathrm{S}}^{35}$ and DNAase separately and allow this virus to attack to E. coli. The series of observation made by the students are as follows:

a) ${\mathrm{P}}^{32}$ labelled phage particles were produced in E. coli.
b) ${\mathrm{S}}^{35}$ containing phage particles were produced E. coli.
c) Phage particles were observed in E. coli.

d) ${\mathrm{P}}^{32}$ was not observed in phage particles produced by E. coli.
e) ${\mathrm{S}}^{35}$ was not observed in phage particles produced by E. coli.

The correct observations are