Respuesta :
Given statement is false
Explanation:
According to dispersive model of DNA replication,DNA molecules are hybrids of parental and daughter DNA;In this model each individual strand is a combination of original and new DNA
Meselson and Stahl did an experiment on DNA replication using E.coli bacteria
- E.coli was grown in a medium containing heavy isotope of nitrogen,bacteria took up the nitrogen and used to synthesize new biological molecules,including DNA
- It was grown for many generations,the nitrogenous bases of the bacteria's DNA were all labelled with heavy nitrogen
- Bacteria were then switched to light nitrogen isotope and allowed to grow for several generations
- They then measured the density of the DNA using density gradient centrifugation
- This method separates molecules such as DNA into bands by spinning them at high speeds in the presence of another molecule, such as cesium chloride
- Each DNA produced two DNA molecules each with one new strand and one old strand called semi conservative replication(half of the parental DNA conserved in daughter DNA)
- Each DNA strand act as a template for synthesis of new strand
- Hence,dispersive model of DNA was eliminated and semi-conservative model of DNA replication was proved by the above experiment
Answer:
False
Explanation:
Meselson-stahl experiment: The experiment done by Meselson and Stahl demonstrated that DNA replicated semi-conservatively, meaning that each strand in a DNA molecule serves as a template while DNA replication for synthesis of a new, complementary strand.
The conservative model was eliminated because according to it, there would be 2 bands, one representing the parental DNA at one density and other representing the daughter DNA at a different density. The result from the Meselson–Stahl experiment after one generation was consistent with both the semi-conservative as well the dispersive model.
