About what percentage of all existing transgenic animals are mice?

Match the following:

Column-$I$	Column-$II$
$(1)$ Study of disease	$(p)$ Transgenic mice
$(2)$ Biological products	$(q)$ Testing toxicity of drug
$(3)$ Vaccine safety	$(r)$ Rheumatoid arthritis
$(4)$ Chemical safety	$(s)$ $\alpha-1$ Antitrypsin

If the nucleus of a donor somatic cell is transferred into an enucleated egg cell,which of the following will be true for the resulting organism?

In transgenesis,the expression of the transgene in the target tissue is known as:

Choose the appropriate option for chemical safety testing.

Define/Explain: Transgenic Animals.