Question

The largest chromosome in a particular eukaryote contains 5 x 108 bp. The rate of DNA synthesis is 2500 bp/min at each replication fork. a. How long would it take to replicate the entire chromosome from a single origin of replication located exactly in the middle of the chromosome. Assume no pauses.b. Research reveals that it takes only 10 minutes for an actively growing cell to replicate the entire chromosome. What is the minimum number of replicons present in this chromosome

Answer 1

a)
`200000` minutes

b)
`20000` number of replicons

Step-by-step explanation:

Given,

Total number of base pairs in a particular eukaryote
`= 5* 10^8`

Rate of DNA synthesis
`= 2500` bp/min

a) Time taken to replicate the entire chromosome from a single origin of replication located exactly in the middle of the chromosome is equal to total number of base pairs divided by rate of DNA synthesis

`= (5* 10^8)/(2500)\\= 200000 minutes\\`

b) Time taken by an actively growing cell to replicate the entire chromosome
`=10 minutes`

The minimum number of replicons present in this chromosome is equal to total time taken for replication divided by time taken by each replicon

`= (200000)/(10) \\= 20000`