(a)(i)Explain the functions of the thyroid hormones ?
(ii)How are stem cells useful in regenerative process ?
(iii)What is palaeontology ?

Explanation

(i) Functions of the thyroid hormone
Increases oxygen consumption in tissues.
Production of energy by maintaining the Basal Metabolic Rate (BMR) of the body.
Helps to maintain normal body temperature.
Controls growth of the body, bone formation and development of gonads.
Essential for normal physical, mental and personality development. Hence also known as personality hormone
(ii)Stem cells useful in regenerative process
Sometimes cells, tissues and organs in the body may be permanently damaged or lost due to genetic condition or disease or injury
In such situations, stem cells are used for the treatment of diseases, which is called stem- cell therapy. In treating neurodegenerative disorders like Parkinson.s disease and Alzheimer.s disease neuronal stem cells can be used to replace the damaged or lost neurons.
(iii) The study of fossils is known as Palaeontology.