The organism previously used 15N for replication so all the DNA molecules were of 15N15N type. Then the organism is shifted to a medium where only 14N is available for replication.
According to semi conservative mode of replication, a newly synthesised DNA molecule consists of one new strand and one parental strand. So after the first round of replication, All the 15N strands will synthesise new DNA strands using 14N resulting into intermediate 15N14N DNA molecules. Hence, only one band would be observed (15N14N) above the original 15N15N band since 15N14N has lighter isotope too so it will be lighter than 15N15N molecules and will lie above it.
After second round of replication, 15N strand from 15N14N would synthesise another 14N strand. 14N strand from 15N14N molecules will also synthesise another 14N strand. So now, 50% of the DNA molecules will be of 15N14N intermediate type and 50% of them will be of 14N14N type.Two bands will be observed above the original 15N15N band. One band of 15N14N molecules will be right above it and other band of 14N14N molecules will be even higher because it is the lightest band since it has only the lighter isotope of nitrogen.

8 0

3 years ago

The wings of birds and butterflies have the same function—they enable the organisms to fly. Which statement can be made about th

Marta_Voda [28]

This character trait is known as homoplasy. the definition of homoplasy that two or more species share a character, but they did not descend from a common ancestor.

This trait is known as convergent evolution, or convergence.

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Explain how the terms speed velocity and acceleration are related to each other

muminat

Acceleration is a little more complicated. It is defined as the rate of change of the object's velocity over its change in time. ... Or, if the acceleration is negative, it's called deceleration and describes something slowing down. For something to speed up or slow down, it has to have a certain change in velocity

3 0

3 years ago