DNA So Far

If the distance between two consecutive base pairs is 0.34 nm and the total number of base pairs of a DNA double helix in a typical mammalian cell is 6.6 × 10⁹ bp, then the length of the DNA is approximately

• 2.2 meters

• 2.7 meters

• 2.0 meters

• 2.5 meters

If a dsDNA molecule consists of 15% adenine, the total amount of pyrimidine N-bases present in this DNA molecule will be

• 15%

• 35%

• 50%

• 70%

A DNA molecule was observed with 18% guanine in it. To which of the given organisms, this DNA could belong?

• E coli

• Streptococcus

• Saccharomyces

• Nostoc

Tags

NGSS.HS-LS1-1

Mark the option that depicts correct labelling for image given below.

• 
• A

• B

• C

• D

Which of the following is not found in a single deoxyribonucleotide?

• Phosphodiester bond

• Phosphoester bond

• N-glycosidic Bond

• Nitrogenous base

A strand of DNA has ATGGGCTCACATTTGC nucleotide sequence. What will be the sequence of nucleotides in the second strand of this DNA molecule?

• ATGGGCTCACATTTGC

• GCAAATGTGAGCCCAT

• TACCCGAGTGTAAACG

• CGTTTACACTCGGGTA

End to end length of a DNA molecule is 23.8 nm. How many base pairs would be present in such DNA?

• 50

• 60

• 70

• 80

While analysing the nucleic acid of an organism the proportion of different base is Adenine = 29%, Guanine = 17%, cytosine = 32%, thymine = 17%. it be concluded that

• Organism has double strand circular DNA

• This molecule is a single stranded DNA

• Organism studied is an RNA virus

• No conclusion can be drawn

Base ratio of DNA extracted from an organism is observed to be 0.49. This indicates that

• This DNA molecule is extracted from a eukaryote

• It has a lower melting temperature

• It has more G-C pairs compare to A-T pairs

• It does not have equal purine and pyrimidine bases.

X-Ray diffraction of DNA was produced by

(a) James Watson

(b) Maurice Wilkins

(c) Rosalind Franklin

(d) Erwin Chargaff

• a and b

• b and c

• c and d

• a and d