Palaeontologists unearthed a human skull during excavation. A small fragment of the scalp tissue was still attached to it. Only little $DNA$ could be extracted from it. If the genes of the ancient man need to be analysed, the best way of getting sufficient amount of $DNA$ from this extract is

Differentiation of organs and tissues in a developing organism, is associated with

Consider the following statements

$I$. Transgenic animals are more sensitive to the toxic substance than non-transgenic animals

$II$. Useful biological products can be produced by introducing into transgenic animals the portion of $DNA$ which codes for a particular product

$III$. Brazzein is a protein produced by a west African plant, Pentadiplandra brazzeana which is approximately $2000$ time as sweet as sugar

Which of the statements are given above are correct?

Which one of the following is the correctly matched pair of a product and the microorganism responsible for it

Hirudin can be extracted from transgenic plant