The genome of D. melanogaster consists of approximately 1.7 * 108 base pairs. DNA synthesis occurs at a rate of 30 base pairs per second. In the early embryo, the entire genome is repli- cated in five minutes. How many bidirectional origins of synthesis are required to accomplish this feat?

9444.44 origins

Explanation:

From the given information:

The genome of D. melanogaster = 1.7 × 10⁸

1 sec = 30 base pair

1 min = 1800bp i.e. (30  × 60 = 1800)

5 Min = 9000 bp i.e. (1800 × 5 = 9000)

Suppose there was a single bidirectional origin, then the process would proceed as:

= 1.7 × 10⁸ / 2*(1 / sec / 30 bp)

= 2833333.333

SInce it only takes 300 seconds in ( 5 minutes), then:

There should be 2833333.333/300 = 9444.44 origins to accomplish suh feat.