LABORATORY REVIEW
MOLECULAR BIOLOGY
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
run in opposite directions (antiparallel)
|
|
|
run in perpindicular directions
|
|
|
run in the same direction (parallel)
|
|
|
run in random directions
|
Detailed explanation-1: -The two polynucleotide strands run ‘antiparallel’ to each other, with nitrogenous bases projecting inwards. The term ‘antiparallel’ means that the strands run in opposite directions, parallel to one another. The antiparallel strands twist in a complete DNA structure, forming a double helix.
Detailed explanation-2: -One strand of DNA run from 5’ to 3’ end while other run from 3’ to 5’ end, thus antiparallel in nature. The DNA strands are complementary to each other because of the nitrogenous bases as A only binds to T and C only binds to G.
Detailed explanation-3: -The importance of an antiparallel DNA double helix structure is because of its hydrogen bonding between the complementary nitrogenous base pairs. If the DNA structure were to be parallel, the hydrogen bonding would not be possible, as the base pairs would not be paired in the known way.
Detailed explanation-4: -Due to the base pairing, the DNA strands are complementary to each other, run in opposite directions, and are called antiparallel strands.
Detailed explanation-5: -The strands of a DNA double helix are said to be “antiparallel” because they have the same chemical structure, but are opposite in direction.