Chapter 5: Nutrition

Why do we need food?

to provide energy - to synthesize protoplasm - maintain health and prevent deficiency

Carbohydrate

organic compounds made up of the elements made up of the elements carbon, hydrogen and oxygen

Fats

are organic compounds made up of the elements carbon, hydrogen and oxygen but, unlike carbohydrates, they contain much less oxygen in proportion to hydrogen.

Proteins

are complex organic substances containing carbon, hydrogen, oxygen and nitrogen

Vitamins

are group of chemically unrelated organic compounds required in the diet of humans in minute amounts

Minerals

are inorganic salts which do not provide energy but are indispensable to bodily functions

Water

is the essential constituent of protoplasm

Function of Carbohydrates

source of energy
helps in forming a supportive structure
formation of nucleic acid
to produce nectar in some plants

Function of Proteins

essential for the synthesis of protoplasm
for growth and repair of worn out body cells
for synthesis of enzymes and hormones
for formation of antibodies to combat disease

Function of Fats

storage form of energy
insulating material beneath the skin to prevent heat loss
as a solvent for fat soluble vitamins and many other vital substances such as hormones