Question

Which of the following macromolecules function as energy storage compounds, components of cell membranes and can also provide insulation?

• A. Proteins
• B. Carbohydrates
• C. Steroids
• D. Lipids
• E. Nucleic acids

Answer 1

Answer: (D)

Lipids

A. Proteins are the polymer of amino acids which are connected via peptide bond. Proteins account for more than 50% of the dry weight of most cells and make up about 15% by mass of our body. They are involved in structural support, storage, transport, signalling etc.

B. Carbohydrates are the compounds of carbon, hydrogen and oxygen. They are the complex organic molecules that are broken down to release energy.

C. Steroids are the derivatives of lipids. They are isoprenoid structures and are involved in regulation of carbohydrate metabolism.

D. Lipids are the hydrophobic compounds made up of carbon, hydrogen and oxygen. They act as reserve food material and store energy. They also act as insulation coats. Phospholipids which are a kind of lipids, are the major structural components of cell membranes.

E. Nucleic acids constitute the genetic material of all living organisms. Two important nucleic acids present in living cells are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).

So, the correct answer is Lipids.