Desired genes have been introduced into transgenic animals to obtain large-scale production of useful biological products encoded by these genes. This approach is generally referred to as

What is produced from yeast?

Which therapy can be used to treat the genetic disorder $S.C.I.D.$?

Statements related to human insulin are given below. Which statement$(s)$ is/are correct about genetically engineered insulin?
$(a)$ Pro-hormone insulin contains an extra stretch of $C$-peptide.
$(b)$ $A$-peptide and $B$-peptide chains of insulin were produced separately in $E. coli$,extracted,and combined by creating disulfide bonds between them.
$(c)$ Insulin used for treating diabetes was extracted from cattle and pigs.
$(d)$ Pro-hormone insulin needs to be processed for converting into a mature and functional hormone.
$(e)$ Some patients develop allergic reactions to the foreign insulin.
Choose the most appropriate answer from the options given below:

List the disadvantages of insulin obtained from the pancreas of slaughtered cows and pigs.

$ELISA$ is based on: