NEET BIOLOGY

GENETICS AND EVOLUTION

EVOLUTION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
The double helix backbone of DNA is formed from which structural features:
A
Phosphate and deoxyribose
B
Phosphate and nitrogenous base
C
Deoxyribose and Nitrogenous base
D
None of the above
Explanation: 

Detailed explanation-1: -A phosphate backbone is the portion of the DNA double helix that provides structural support to the molecule. DNA consists of two strands that wind around each other like a twisted ladder. Each strand has a backbone made of alternating sugar (deoxyribose) and phosphate groups.

Detailed explanation-2: -The DNA double helix is anti-parallel, which means that the 5’ end of one strand is paired with the 3’ end of its complementary strand (and vice versa). As shown in Figure 4, nucleotides are linked to each other by their phosphate groups, which bind the 3’ end of one sugar to the 5’ end of the next sugar.

Detailed explanation-3: -This backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.

Detailed explanation-4: -The ‘sides’ of the ladder (or strands of DNA) are known as the sugar-phosphate backbone. This backbone consists of alternating phosphate and sugar groups, with the sugar molecule of one nucleotide linking to the phosphate group of the adjacent nucleotide.

There is 1 question to complete.