How many replication origins would you need to complete DNA replication if the replication fork can move at 75 nucleotides per second?

Question

Answer 1

Each replication origin forms 2 replication forks, one in each direction from the origin. So, each origin leads to 150 nucleotides / second

8 hr X 3600 seconds/hr = 28800 seconds

6,000,000,000 nucleotides / 28800 s = 208333 nucleotides / second must be synthesized

208333 nucleotides/s / 150 nucleotides/s / origin = 1389 origins or about 1400 origins