Question

Which category of compound is the most concentrated energy source?
A. Lipid
B. Carbohydrates
C. Proteins
D. Vitamins

Answer 1

Hint: Food is composed of energy and non- energy components. The energy in the body is obtained via calories which is very important for the body cells to function properly.

Complete answer:
The food components which provide the energy to the body are carbohydrates, proteins, fats/ Lipids, vitamins and minerals.
-Carbohydrates: are the carbon, hydrogen and oxygen compounds. It is the vital energy source. The staple food of India contains a high source of carbohydrates. It provides energy for daily activities and promotes good digestive health as well. Carbohydrates are of: Simple and complex carbohydrates. Simple carbohydrates are in honey, table sugar etc. whereas complex carbohydrates include starch found in bread, pasta, potatoes whereas dietary fibres found in oats, whole grains, vegetables and fruits. Carbohydrates imparts the blood glucose level.
-Proteins: It is made up of hydrogen, nitrogen, carbon, oxygen, sulphur and phosphorus. It is one of the important nutrients which helps the body to repair, build and renew the organs and the damaged tissues in our body. Protein is mainly found in nuts, eggs, fish, dairy and seafood.
-Vitamins: are the organic compounds acting as a catalyst for during reaction of metabolism. It helps in the growth and development of the body. There are different vitamins like A, B,C, D, E and K. These vitamins have different roles in the body and each and every vitamin is crucial for the body. These are mainly found in fruits, vegetables, cereals etc.
-Lipids: are the naturally occurring substances which include fats, sterols, monoglycerides, diglycerides, triglycerides and phospholipids. The important functions of lipids are storing energy, signalling and they act as a structural component of cell membranes. Triglycerides are stored in adipose tissue which helps in storing energy in humans and animals. The fat cell is made in such a manner where continuous synthesis and degradation of triglycerides occurs with the breakdown controlled by the enzyme lipase. The complete oxidation of fatty acids gives the caloric content around 9Kcal/g whereas 4 Kcal/g for breaking carbohydrates and protein.

Hence, the correct answer is option (A).

Note: Triglycerides are non -polar and can be stored in anhydrous form and complete oxidation of fatty acids gives the yield 9Kcal/g. In birds it is found that they can fly longer with the stored energy of triglycerides acting as a fuel for them.