Answer is (E) : Amino acids (and thus proteins) also have nitrogen atoms; thus, the radioactivity would not distinguish between DNA and proteins.
Let me explain you why. Hershey and Chase conducted their experiment to show what is the genetic material that passes from one generation to another generation. Is it protein or DNA? For explaining this, they allowed the virus to grow in the presence of two different radio active elements.
In one set they grew viruses in the presence of P-32 radio-active element
In another set they grew viruses in the presence of S-35 radio active element.
The reason why they choose these two radio-active element was, phosphorus is present in DNA but not in proteins and similarly sulphur is found in proteins but not DNA.
These viruses were allowed to infect bacteria and the later was observed to be radio-actively labelled with P-32 but not S-35. This clearly showed that DNA is the genetic material which was passed from virus to bacteria.
Now if you choose Nitrogen for labeling, it won't help you in getting any conclusion since nitrogen is present in both proteins and DNA.
21. B. recessive
22. D. DD and dd
23. D. FF and ff
Answer:
Well I think your able to identify by looking at the Physical and Chemical Properties or by its Melting or boiling point.
Hopefully this is correct
Answer:
It is likely that the genomic sequences that were used did not enable to properly observe the evolutionary relationships among the species analyzed
Explanation:
The homology level between the genomic sequences may be too low to separate species that are phylogenetically related. In these cases, it is necessary to make a genetic analysis of the sequences that are used before the phylogenetic analysis
I BELIEVE the answer is D) 4.