Cretinism is a disease caused by hypothyroidism (less thyroxine formation) . The symptoms of the disease are retardation of mental, physical and sexual developments. potbelly, protruding tongue, dry skin etc are also indicative of this disease.

The Chloroplast contains the wonder green pigment chlorophyll which is able to trap solar energy and use it for synthesis of food

The biogenetic law states that ontogeny (study of development) repeats phylogeny (origin from previous group of racial history), The young one of the frog namely the tadpole is like a fish cosidered to be ancestral to frog.

The hormone adrenaline also called epinephrine is known as a stress harmone. In emotional upset (like fear, anger etc.) this harmone is poured into the blood and it accelerates heart beat. The hormone acetylcholine decelerates heartbeat rate.

It gets contaminated by lead