CHAPTER -2 COMPONENETS OF FOOD

Transcription

1 CHAPTER -2 COMPONENETS OF FOOD Balanced Diet (P- 22) A. Define the following: 1. Balanced diet: The diet that contains all the nutrients in right quantities and it also contain good amount of roughage and water is called balanced diet. 2. Obesity: When a person eats too much fat-containing foods, then the fat gets deposited in the body and he may end up suffering from a condition called obesity. Objective Type Exercises: B. Fill in the blanks: (P-25) 1. Carbohydrates occur in the form of starch and sugar. 2. Carbohydrates and fats give us energy but fats give us more energy than carbohydrates. 3. Eating too much of fat rich foods may lead to a condition called obesity. 4. The component of food that does not provide any nutrient to our body and yet is essential in our food is roughage/water. 5. The vitamin that gets easily destroyed by heating during cooking is vitamin C. 6. If a food has a greater amount of a nutrient, then it is a rich source of that nutrient. 7. Deficiency diseases can be prevented by taking a balanced diet. 8. Egg yolk is rich in fats and egg albumin is rich in proteins.[ncert] 9. Rickets is caused by deficiency of Vitamin D.[NCERT] 10. Deficiency of vitamin B1 causes a disease known as beri-beri.[ncert]

2 11. Deficiency of Vitamin C causes a disease known as scurvy.[ncert] 12. Night blindness is caused due to deficiency of vitamin A in our food.[ncert] E. Name the vitamin needed to: (P-26) 1. Keep bones and teeth healthy Vitamin D 2. Fight against diseases Vitamin C 3. Maintain healthy hair Vitamin E 4. Help blood clotting Vitamin K F. Give one word answer: (P-26) 1. Chemical used to perform a test for presence of starch:_iodine Solution 2. The nutrients that are needed for the growth and maintenance of our body:[ncert] Protein 3. The nutrients which mainly give energy to our body:[ncert] Carbohydrate 4. A vitamin prepared in the presence of sunlight:_vitamin D 5. A vitamin required for maintaining good eyesight:[ncert] Vitamin A 6. A deficiency disease in which glands in the neck become swollen:_goitre 7. A mineral that is required for keeping our bones healthy: Calcium Subjective type: Very Short Answer Questions: 1. What are nutrients? Ans: The components of food which are needed by our body for growth and development are called nutrients are called nutrients. 2. Name the major nutrients present in our food.[ncert]

3 Ans: The major nutrients in our food are named carbohydrates, proteins, fats, vitamins and minerals. In addition, food contains dietary fibres and water which are also needed by our body. 3. Why do we need nutrients in food? Ans: We need nutrients in food because they provide us energy and are essential for body growth, repairing damaged cells as well as for fighting against diseases. 4. Why do we need proteins? Ans: Proteins are needed for growth and repair of damaged cells of the body. They help our body to fight against infections. Proteins make our nails, hair and muscles. They are called body building food. 5. List some food items which are usually present in our meal. Ans: Individual answers 6. Why is it not possible for us to eat a large variety of food items most of the time? Ans: It is not possible to eat a variety of food items most of the time because: We can t prepare so many items due to shortage of time. Most of us eat in a hurry. Our stomach can t occupy too much of food. 7. How do we fulfil the water requirement of our body? Ans: We get most of the water that our body needs from the liquids we drink such as water, milk and tea. Fresh fruits and vegetables have large portions of water. Apart from this, we also add water while cooking many food items. B. Short Answer Questions 1. State the common meals if you are eating food in the following states: (a) Punjab (b) Andhra Pradesh (c) West Bengal

4 Ans: Individual answers 2. Do all foods contain all the nutrients? Explain with examples. Ans: No, all foods do not contain all the nutrients. Some foods are rich in a particular nutrient, while others contain different nutrients. For example, rich in carbohydrates but not in proteins. 3. Briefly explain how will you obtain the following solutions: (a) Iodine solution : A dilute solution of iodine can be prepared by adding a few drops of tincture iodine to a test tube half filled with water. (b) Copper sulphate solution : Copper sulphate solution can be prepared by dissolving 2 gram (g) of copper sulphate in 100 millilitre (ml) of water. (c) Caustic soda solution : 10 g of caustic soda dissolved in 100 ml of water makes the required solution of caustic soda. 4. List few precautions that should be taken while testing given food samples for the presence of carbohydrates, proteins and fats. Ans: -> Do not taste or touch any chemical as it could be dangerous. -> Perform the tests in test tubes, not in hands. -> prepare fresh chemicals for the tests. 5. Is it possible that a food item contains more than one nutrient? How will you confirm it? Ans: Yes, a food item contains more than one nutrient. This can be conformed by performing tests for different nutrients on it. 6. Name the two forms in which carbohydrates are found in food. Write few sources of carbohydrates. Ans: Sugar and starch are mainly the two forms in which carbohydrates are found in food. Potato, rice and wheat are few sources of carbohydrates.

5 7. Why does our body need dietary fibres or roughage? Name some sources of roughage. Ans: Roughage is essential component of our food and adds to its bulk as this helps our body to get rid of undigested food. Main sources of roughage are whole grains, fresh fruits, salads, vegetables, etc % of our body weight is due to water. Throw light on the importance of water in our food. Or Water does not provide nutrients, yet it is an important component of food. Explain. Ans: Water helps our body to absorb nutrients from food. It also helps in throwing out some wastes from body as urine and sweat. 9. Rahul is fond of helping his mother in household chores. Whenever mother would sit to cut fruits and vegetables, he would sit by her side and watch carefully. He saw that his mother's hands and knife became wet while cutting. He was curious to know why it happened. What would his mother reply? Ans: His mother will reply that the water content in the fruits and vegetables makes her hands and knife wet. 10. Why do we need balanced diet? Ans: We need a balanced diet to maintain good health, growth and meet all the nutrient requirements of our body. 11. Do people of all ages need the same type of diet? Explain with examples. Ans: No, the requirement of people of different ages is different. For example, young children need a lot of protein-rich diet, while adults do not. People who do more physical work, athletes and children need more carbohydrates in their diet.

6 12. Raunak was very fond of fat rich foods, such as rabdi, peda, malai, kheer, etc. and took them in large quantities saying that they provided a lot of energy. Is it a right practice? Why/Why not? Ans: No, it s not a right practice. Too much fat gets deposited under the body skin which leads to a fast weight gainof the person and he becomes fat or obese, lacking of energy to do physical activities. 13. Is it harmful for the body to take too much of some nutrients such as proteins or vitamins in the diet? Explain. Ans: The excessive nutrients are harmful for the body in the following ways: Excessive carbohydrates convert into fats and make us fat or obese. Excessive intake of vitamin K will lead to blood clotting in the blood vessels. Excess minerals accumulate in the body and can damage vital organs such as liver and kidney. 14. What are deficiency diseases? What is the result of deficiency of (a) proteins Ans: stunted growth, swelling of face, discolouration of hair, skin diseases and diarrhoea. (b) carbohydrates Ans: lack of energy, pale skin, weakness. (c) both proteins and carbohydrates Ans: the growth may stop completely. Such a person becomes very lean and thin and so weak that he/she may not even be able to move.