Question

If an eukaryotic chromosome has 6 origins of replication, determine how many ________ TOTAL are present during replication.

-Replication forks

-Polymerase III

-Helicases

-Replisomes

Answer 1

Answer-

a) Replication forks- 12

Resson- For a process of DNA replication, for one origin of replication, there are two replication forks arranged in opposite directions. Therefore for 6 origin of replication, there are 12 replication forks

b) Polymerase III- 24

Reason- In eukaryotes, two molecules of DNA polymerase III at a replication fork are needed. Therefore for 12 replication fork, 24 DNA polymerase III are required. It helps in 5' to 3' polymerization of DNA on a single-stranded DNA template.

c) Helicases- 12

Reason- Helicase is the unzipping enzyme which helps in the formation of replication fork. So, for each replication fork, there will be a helicase molecule present.

d) Replisomes- 12

Reason- Replisome is a complex which contains the enzymes for unzipping and DNA elongation. Since there is one such complex for each Replication fork, there will be 12 replisomes in total.