Which of the following hormones does not contain a polypeptide?
a)	Prostaglandin	b)	Oxytocin
c)	Insulin	d)	Antidiuretic hormone

(b)

Prostaglandin does not contain polypeptide. Prostaglandins are fatty acid derivatives.  They are secreted by many organs (like kidney, gonads, seminal vesicles, thymus etc.) into their tissues. It was first reported in semen of man and produced by prostate gland.  It contains either contraction/relaxation of smooth muscles or dilation/ contraction of blood capillaries.