BIOLOGY
NUCLEIC ACIDS
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
5’ T T T A A A G 3’
|
|
|
3’ T T T A A A G 5’
|
|
|
5’ A A A T T T C 3’
|
|
|
3’ U U U A A A G 5’
|
Detailed explanation-1: -Leading and lagging strands One new strand, the leading strand, runs 5’ to 3’ towards the fork and is made continuously. The other, the lagging strand, runs 5’ to 3’ away from the fork and is made in small pieces called Okazaki fragments.
Detailed explanation-2: -DNA is always synthesized in the 5’-to-3’ direction, meaning that nucleotides are added only to the 3’ end of the growing strand.
Detailed explanation-3: -Leading Strand and Lagging Strand The first one is called the leading strand. This is the parent strand of DNA which runs in the 3’ to 5’ direction toward the fork, and it’s replicated continuously by DNA polymerase because DNA polymerase builds a strand that runs antiparallel to it in the 5’ to 3’ direction.
Detailed explanation-4: -Chunks of DNA, called Okazaki fragments, are then added to the lagging strand also in the 5’ to 3’ direction. This type of replication is called discontinuous as the Okazaki fragments will need to be joined up later.