Explain the various steps involved in the production of artificial insulin.
Insulin used for diabetes was earlier extracted from pancreas of slaughtered cattle and pigs.
It consist of two short polypeptide chains- chain A and chain B that are linked together by disulphide bridges.
In mammals even in humans, insulin is synthesised as a pro-hormone also need to be processed before it becomes a fully mature and functional hormone. It contains an extra stretch called C-peptide.
C-peptide is absent in the mature insulin and is removed during maturation into insulin.
Production of insulin by rDNA techniques was achieved by an American company, Eli Lilly in 1983. It prepared two DNA sequences corresponding to A and B, chains of human insulin and introduced them in plasmids of E. coli for production.
The A and B chains produced were separated, extracted and combined, by creating disulfide bonds to form human insulin.
Fill in the blanks:
(a) Humans reproduce __________. (asexually/sexually)
(b) Humans are__________. (oviparous/viviparous/ovoviviparous)
(c) Fertilization is __________ in humans. (external/internal)
(d) Male and female gametes are __________. (diploid/haploid)
(e) Zygote is __________. (diploid/haploid)
(f) The process of release of the ovum from a mature follicle is called__________.
(g) Ovulation is induced by a hormone called the __________.
(h) The fusion of male and female gametes is called _____________.
(i) Fertilisation takes place in _____________.
(j) Zygote divides to form _____________which is implanted in uterus.
(k) The structure which provides vascular connection between fetus and uterus is called ____________.