Question

What are 'nucleic acids'?
Define complex lipids. Mention any 'two' functions of lipids.

Answer 1

'Nucleic acids' are esters of phosphoric acid with sugar. Sugar is linked to nitrogen bases. Nucleic acids are present in nucleus of every cell and transmits the inherent characters. DNA and RNA are two types of nucleic acids.
Complex lipids:
They are esters of long chain fatty acids and can be hydrolyzed. They include triglycerides (animal fats and vegetable oils), glycolipids, phospholipids and waxes.
Functions of lipids:
(1) Waxes provide vital waterproofing for body surfaces. Waxes repel water and form protective coatings on leaves, fruits, berries, animal fur and feather of bird.
(2) Prostaglandins can lower blood pressure, affect blood platelate aggregation during clotting, lower gastric secretion and stimulate uterine contractions during child birth.