define food substance, classification of food substance, types of carbohydrates
Answers
Answer:
Food is any substance normally eaten or drunk by living things. The term food also includes liquid drinks. Food is the main source of energy and of nutrition for animals, and is usually of animal or plant origin.
In other words it is any substance containing nutrients, such as carbohydrates, proteins, and fats, that can be ingested by a living organism and metabolized into energy and body tissue.
Food Substances All living organisms need food for their survival and daily activities. Plants can manufacture their food through the process of photosynthesis, hence they are called autotrophs. On the other hand, animals cannot manufacture their food as they depend on plants directly or indirectly for their food, hence they are called heterotrophs.
All the food eaten or taken in by an animal can be classified or divided into seven groups of food substances. These food substances are:
- Carbohydrates
- Proteins
- Fats and oils
- Mineral salts
- Vitamins
- Water
- Roughages
Carbohydrate is made up of carbon, hydrogen and oxygen. The ratio of hydrogen to oxygen is 2:1 as in the case with water. The main sources of carbohydrate include yam, rice, maize, millet, guinea corn, potatoes, bread, garri etc.
Types of Carbohydrates
There are three major types of carbohydrate. These are:
a. Monosaccharides (Simple sugars): They are the simplest sugar and have only one unit of simple sugar. Examples are glucose, fructose and galactose.
b. Disaccharides (Reducing sugars): These contain two units of simple sugars, examples are sucrose, maltose and lactose.
c. Polysaccharides (Complex sugars): These consists of more than two simple sugars or several simple sugars joined together. Examples are starch, cellulose, chitin and glycogen (animal fat).