Chapter Notes and Summary
• Food is essential for living organisms. It :
• provides energy to carry out various life functions.
• helps in growth and repair of cells.
• protects body from various diseases.
• keeps body fit.
• Nutrition is process by which our body takes in food and uses it for growth and development.
• Food has nutrients which are required by our body for maintaining good health.
• substances from which food is made are called ingredients.
• We get food from plants and animals.
• Producers can prepare their own food. e.g., green plants.
• Consumers are animals which depend on green plants for their requirement of food.
• Various types of oils are used for cooking. e.g., mustard oil, seasame oil etc.
• On basis of type of food consumed, people are calegorised as vegetarian and non-vegetarian. Vegetarians do not eat meat.
• Animals that eat only plants are called herbivores. e.g., cow, buffalo, deer etc.
• Animals that eat only other animals are called carnivores. e.g., lion, tiger, wolf etc.
• Animals that eat both plants and animals are known as omnivores. e.g., Human beings, bear and crow.
• Animals that consume dead bodies of other animals and plants are known as scavengers. e.g., Hyena, jackal, vulture etc.
• organisms that decompose organic components in remains of dead plants and animals are known as decomposers. e.g., bacteria and fungi.
• organisms that live on or inside body of other living organism and obtain food from them are called parasites. e.g., fleas, leeches etc.
• organisms that provide food and shelter to a parasite are called hosts.
• sequence of eating and being eaten is called food chain. e.g., Grass → Cow → Tiger
• A network of inter connection of food chains is called a food web.