CBSE Notes Class 6 Science - Food : Where Does it Come From?

Food is any substance consumed to provide nutritional support to the body. It is usually of plant or animal origin and contains essential nutrients such as carbohydrates, fats, proteins, vitamins and minerals. Food eaten by an organism is used by the cells of the body to produce energy, maintain life and stimulate growth.

1.0Important terms 

• Meal : The food consumed at a particular time of the day. 
• Breakfast : Food taken in the morning constitutes a meal called breakfast. 
• Lunch : Food eaten in the afternoon.  
• Dinner : Food eaten in the evening / night. 
• Ingredients : Materials needed to prepare a dish.
• Menu : List of dishes / food items served at a meal.

2.0Functions of food 

• Food is required by the body for the following purposes :
• For energy : Food is required to provide energy which helps in performing various functions of the body to sustain life. 
• For growth : You have seen yourself growing. Without proper food, your growth would not be possible. 
• For protection : Food protects us from diseases and infection. 
• For repair of injured and damaged body parts : When we get hurt, the skin is damaged and blood is lost. Repair of such damaged parts takes place by addition of new cells.

Food eaten by living organisms 

• All living organisms need food. 
• On the basis of food habit, there are three types of animals : 
• Herbivores: These animals eat only plants or plant products e.g. cow, elephant, rabbit, horse, panda, zebra, deer.
• Carnivores: These animals eat other animals e.g. lion, tiger, lizard, wolf, owl.  
• Omnivores: These animals eat both plants and animals e.g. dog, cat, crow, pig, rat, fox, bear, ant, shark, whale.

3.0Sources of food (plants, animals) 

Both plants and animals provide us with food. 

• Plants as a source of food Plant food includes cereals, pulses, vegetables, fruits, sugar, tea, coffee, spices and oils. 
• Cereals : e.g. wheat, rice, maize. 
• Pulses : e.g. pea, bean, gram and soybean. 
• Vegetables : e.g. carrot, radish, potato, onion, cabbage, tomato and spinach etc. 
• Fruits : e.g. banana, mango, apple and grapes 
• Spices : e.g. ginger (adrak), turmeric (haldi), pepper (kali mirch) and chillies (mirch), cardamom (ilaichi), cloves (laung). 
• Oils : e.g. cotton seed, ground nut, mustard, coconut, soyabean, sunflower. (vii) Sugars : e.g. sugarcane and sugar beet. 
• Beverages : e.g. tea and coffee.

4.0Parts of Plant used as food 

The following list gives some common vegetables along with the part used. 

5.0Animal products as source of food 

• Animals provide us food in the form of milk, meat (like beef and pork), eggs, fish, chicken and honey. 
• Milk yielding animal : Cow, buffalo and goat. It is a very nutritious substance and rich source of proteins. It also contains calcium which is required for healthy bone growth. Many products can be made from milk e.g. paneer, cheese, butter, ghee, curd  
• Meat yielding animals : Sheep, goat and pig . 
• Honey : Honey is the sweet liquid made by bees from flower nectar. 
• Eggs and chicken : Eggs are a very good source of protein, vitamins and minerals. Chicken contains a lot of proteins, vitamins and minerals which improve the immune system.
• Fish : Especially rich in protein, vitamin D and fat.

6.0Some Steps to Avoid Wastage of Food 

• Food in our country is not available in sufficient quantities to all people. 
• Some do not have enough money to buy. 
• Because of this reason, these people suffer from diseases. So we must ensure the following
• Food that is produced should not be allowed to 

(i) Get spoiled

(ii) Plenty of food is thrown out because too much food is cooked. 

(iii) Eaten away by animals like rats and squirrels. 

• We should eat only that quantity of food which is required by our body. Excess eating will lead to obesity (growing fat). 
• In parties or even in our homes we should not leave food uneaten in our plates.