AP BIOLOGY

Detailed explanation-1: -Despite these small chemical differences, DNA and RNA differ quite dramatically in overall structure. Whereas DNA always occurs in cells as a double-stranded helix, RNA is single-stranded.

Detailed explanation-2: -DNA is a double-stranded molecule that has a long chain of nucleotides. RNA is a single-stranded molecule which has a shorter chain of nucleotides.

Detailed explanation-3: -DNA is made of two linked strands that wind around each other to resemble a twisted ladder-a shape known as a double helix. Each strand has a backbone made of alternating sugar (deoxyribose) and phosphate groups. Attached to each sugar is one of four bases: adenine (A), cytosine (C), guanine (G) or thymine (T).

Detailed explanation-4: -RNA, like DNA, can form double helices held together by the pairing of complementary bases, and such helices are ubiquitous in functional RNAs.

Detailed explanation-5: -It’s structure! RNA’s structure is such that it CAN NOT bond to a complementary strand due to the interference that can occur between the 2’hydroxyl in its ribose sugar, and the N-bases. DNA Lacks this 2’hydroxyl because it does not have ribose, but Deoxyribose as its sugar.