Answer: conservative model
Explanation: DNA isolated after one generation produced a single band which was a higher and intermediate in density between the heavy and light Nitrogen isotopic DNA used, showing that the first generation was a hybrid DNA. This observation fit with the dispersive and semi-conservative models only. And so at this generation, the conservative model was discarded.
Answer:
A. Natural selection results in those individuals within a population who are best-adapted surviving and producing more offspring. The traits that promote survival are heritable.
Explanation:
Natural selection works on the genetic variations that are already present in the natural populations. Some organisms of a population are more likely to produce more offspring than the others. This is due to the presence of beneficial genetic traits in these individuals that impart survival and reproductive fitness to them. Natural selection favors those individuals. Over the generations, the frequency of the beneficial genetic trait in the population increases.
Hémoglobin =other name for blood
If a bacterium cannot use citrate agar will not change its color (stays green). On the other hand, if bacteria have the ability to use citrate, the medium will change its color from green to blue.
This happens because citrate agar contains pH indicator such as bromothymol blue which transforms from green to blue in alkaline conditions.