KSEEB Solutions for Class 8 Science Chapter 18 Food and Its Constituents

Karnataka Board Class 8 Science Chapter 18 Food and Its Constituents

KSEEB Class 8 Science Chapter 18 Textual Questions & Answers

I. Four alternatives are given to each of the following incomplete statement/ question, choose the right answer.

Question 1.
The major compound present in the bones is made up of the following metal
(a) Sodium
(b) iron
(c) calcium
(d) phosphorus
Answer:
(c) calcium

Question 2.
Children are fond of eating too much of bakery products and chocolates. Elders advise them to eat vegetables also and not to keep aside curry leaves while eating food items. This shows the importance of
(a) Carbohydrates
(b) dietary fibers
(c) proteins
(d) lipids
Answer:
(b) dietary fibers

Question 3.
A green leaf that has fallen down from a plant is taken and kept in water for sometimes and then taken out, it is then dipped in spirit and iodine solution. The leaf turns bluish indicating the presence of
(a) Starch
(b) oil
(c) protein
(d) fiber
Answer:
(a) Starch

II. Fill in the blanks with suitable words:

Question 1.
Emulsion test is conducted to detect ……………
Answer:
Fats and oils

Question 2.
Fat soluble vitamins are A,D,E and ………….
Answer:
k

Question 3.
Amino acids contain the elements carbon hydrogen, oxygen and ……………
Answer:
nitrogen

Question 4.
The micro nutrient that is responsible for transportation of oxygen to the different part of the body contains the metal ………….
Answer:
Iron

Question 5.
Biuret solution contains sodium hydroxide and …………
Answer:
Copper sulfate

III. Match the following:
KSEEB Solutions for Class 8 Science Chapter 18 Food and Its Constituents iii
Answer:

  1. (d)
  2. (f)
  3. (a)
  4. (b)

IV. Answer the following:

Question 1.
Why should we have variety in our diet?
Answer:
We do not get all the essential elements from just one type of food. Hence we should have variety in our diet to get all the nutrients that we need for our body.

Question 2.
List four major sources of carbohydrates to the people in your region.
Answer:
The sources of carbohydrates are cereals, sugar, jigger potatoes etc.

Question 3.
What food items used in your region gives lipids to the people who consume them?
Answer:
Oils and fats are the main food items. Butter, cheese, cream, fatty metals are the food items which give lipids.

Question 4.
List the nutritional in the importance of proteins
Answer:
Nutritional importance of proteins,

  1. Some proteins are involved in structural support and some others are involved in bodily movement.
  2. Proteins assist on building up defense against germs
  3. Enzymes which facilitate the biochemical reaction are also proteins.
  4. Hormones are also proteins
  5. Hemoglobin which is present in the blood is also protein.
  6. The proteins like keratin and collagen which are fibrous and tough provide support to tendons and ligaments.

Question 5.
Why do some people suffer from nutritional efficiencies despite having enough food?
Answer:
Despite having enough food some people suffer from nutritional deficiencies since they do not take a completely balanced diet which provides all the nutrients to our body in the right proportion.

Question 6.
Explain the importance of water in our diet.
Answer:
The human body cannot survive without water.

  • Water constitutes about 55 – 75 percent of our body mass.
  • It helps to maintain the health of every cell in the body.
  • It keeps the blood thin enough to flow through blood vessels.
  • It helps to eliminate wastes and excess materials.
  • Water regulates body temperature through sweating.
  • It keeps mucous membranes, lungs, and mouth in moist conditions.
  • It helps digestion and prevents constipation.
  • It improves the texture of the skin and its appearance.
  • It helps to carry nutrients and oxygen to the cells.
  • It also serves as a shock observer inside the eyes, spinal cord, and in the amniotic sac surrounding the fetus in pregnancy.

Question 7.
A beaker contains a thick liquid, How do your test whether it is a lipid?
Answer:
Take 5 ml of the given sample in a test tube. Add a small amount of ethyl alcohol to it. Shake well. Heat the test tube carefully in a water bath. When the sample dissolves in alcohol, filter, or dilutes until you get a clear liquid. Take a small quantity of tap water in another test tube. Pour the solution prepared above gently into the test tube. If a whitish suspension is formed, then the given sample is a lipid.

Question 8.
What is the function of calcium in our bodies?
Answer:

  1. Calcium helps to build bones and teeth
  2. It helps to the proper functioning of muscles heart and nerves, relieves pain and cramps
  3. It helps in the clotting of blood.

Question 9.
List all the major classes of ingredients that should be present in a balanced diet.
Answer:
A Balanced diet should contain a variety of nutrients like carbohydrates, proteins, fats, vitamins, minerals and dietary fiber in the right quantities according to age, sex, size of the body and type of activities to maintain normal health.

Question 10.
Make a list of food items that are rich in dietary fibers.
Answer:
The food items that are rich in dietary fibre are fruits, vegetables, and greens, Cabbage, peas, carrot, turnips, and fruits which have edible skins like apple, guava and pear, cereals and pulses are some of the food items which have high dietary fibre.

Question 11.
Why do children both in rich and poor families suffer from nutritional deficiencies? What are your suggestions to improve the situation?
Answer:
Young children in poor families suffer from nutritional deficiencies due to a lack of proper food. Children raised in a poor family have deprived of a balanced diet or even a meal once a day. Young children in rich families suffer from nutritional deficiency because of having fast food which does not have nutritional value.

We can suggest then having food containing, carbohydrates, proteins, vitamins, iron, calcium-rich food, and those who can’t afford it can help those people through social organizations.

Question 12.
How does lack of nutrition affect your activities, studies and personality? How can you prevent it?
Answer:
When there is a lack of nutrition say for example lack of calcium, magnesium and zinc there are tendencies of being hyperkinetic where a person is unable to sit for more than few minutes and bones will become weak. Lack of proper nutrition affects our activities, studies and personality. This can be prevented by having a balanced diet.

Question 13.
What dietary charges at your home will improve the nutritional status of your family members?
Answer:
Good nutrition is one of the major keys to a healthy life. We can improve our family’s health by resorting to a balanced diet. We should eat food that contains vitamins and minerals. This includes fruits, vegetables, whole grains, dairy products, and some such sources of protein.

KSEEB Class 8 Science Chapter 18 Additional Questions & Answers

Question 1.
What is Food?
Answer:
Food can be defined as a substance which nourishes the body.

Question 2.
Mention the functions of food.
Answer:

  1. Food promotes growth, Supplies energy, Furnishes material for repair of body parts,
  2. Food is also necessary for all metabolic processes and to maintain body temperature constant.

Question 3.
Why should we have variety in our diet?
Answer:
We do not all essential elements from just one type of food. Hence we should have variety in our diet to get all of the things we need for our body.

Question 4.
Define nutrients?
Answer:
Food contains a nourishing substances called nutrients. Nutrients are the ultimate nourishing chemicals found in food.

Question 5.
Name the major constituents of food.
Answer:
The major constituents of food are:

  1. Carbohydrates
  2. lipids
  3. proteins
  4. vitamins
  5. minerals
  6. water and
  7. fiber

Question 6.
Mention the sources of carbohydrates.
Answer:
The sources of carbohydrates are cereals, sugar, jiggers potatoes etc.

Question 7.
What are carbohydrates?
Answer:
Carbohydrates are naturally occurring macronutrients which form a major component of a living organism. They include sugars, starch, and cellulose. These are the compounds made of carbon, hydrogen, and oxygen.

Question 8.
Name the three groups of the constituents of food on the basis of their function.
Answer:

  1. Energy releasing food: Carbohydrates and lipids
  2. Bodybuilding food: Proteins
  3. Protective Food: Vitamin and minerals

Question 9.
Mention the nutritional significance of carbohydrates.
Answer:
The nutritional signification of carbohydrates.

  1. Carbohydrates help in the regulation of sugar in the bloodstream.
  2. Carbohydrates act as a shield and protect muscles.
  3. Fibers present in the carbohydrates such as cellulose keep body movement smooth.
  4. Carbohydrates oxidized in the mitochondrial to release energy during cellular respiration and the energy is used by cells for various metabolic activities.

Question 10.
What are the nutritional disorders due to carbohydrates?
Answer:
Nutritional disorders :

  1. Insufficient supply of glucose may lead to tiredness, weakness and lack, of concentration.
  2. Excess of glucose can lead to obesity.

Question 11.
What are lipids?
Answer:
Lipids are macromolecules which are generally stored in the body lipids include fats, oils, waxes and steroids. Lipids serves as fat reserves.

Question 12.
Write the nutritional significance of lipids.
Answer:
Lipids play a very important role in our body.

  1. They help in brain function, smooth movements of joints, clotting of blood and energy production.
  2. Some lipids help to bring down inflammation within the body and lubricate the joints.
  3. Fats help the body to absorb and to move the vitamin A D E and k.
  4. cell membranes which contain lipids lubricate the cells and this lubrication serves as a protective barrier that controls the movement of materials.
  5. Lipids store more energy and hence help in energy production.
  6. Lipids act as messengers within our bodies.

Question 13.
What are proteins?
Answer:
Proteins are one of the macronutrients which are typically constructed from a set drawn from 20 simple compounds called amino acids.

Question 14.
What are amino acids?
Answer:
Amine acid is the simplest molecule by which protein is formed amino acid molecule consists of atoms of carbon (c), hydrogen (H), a carbonyl group (-COOH), and an amino group (-NH2).

Question 15.
What are vitamins? Name the types of vitamins?
Answer:
Vitamins are a group of organic compounds which are vital for normal growth, development, and maintenance of the body which are required in very small quantities. The vitamins are mainly two types.

  1. Water-soluble vitamin
    eg : Vitamin B and C
  2. Fat-soluble vitamin
    eg : Vitamin A, D, K and E

Question 16.
What do you mean by pro-vitamin?
Answer:
We need certain substances like beta-Carotene and folic acid, which get converted into vitamins in our body. These are called as pro-vitamins.

Question 17.
Mention the major functions of the following

  1. vitamin A
  2. vitamin B
  3. vitamin C
  4. vitamin D
  5. vitamin E

Answer:

  1. Vitamins A: promotes skeletal growth normal tooth structure, healthy skin, eye, and night vision.
  2. Vitamins B: promotes digestion, strengthens the heart muscle, and growth.
  3. Vitamins C: Stops internal bleeding, strengthens blood vessels maintains hard bones and teeth
  4. Vitamins D: Promotes bone and tooth development and normal growth and helps the utilization of phosphorus and calcium.
  5. Vitamins E: It regulates protein and calcium metabolism
  6. Vitamins K: Helps in the clotting of blood, assists in the synthesis of proteins.

Question 18.
What are minerals? Give example.
Answer:
Minerals are the inorganic substance required in small quantities for growth and normal functioning of the body.
eg: calcium (Ca), Iron (Fe), zinc (Zn) and Iodine ( I )

Question 19.
Mention the function of the following minerals.

  1. Ca
  2. Cu
  3. Mg
  4. Zn
  5. I

Answer:

  1. calcium: Calcium helps to build bones and teeth It helps to the proper functioning of muscles heart and nerves, relieves pain, and cramps It helps in the clotting of blood.
  2. Iron: It is a constituent of hemoglobin, which plays an important role in oxygen transport.
  3. Zinc: Zinc in our diet will help to reduce cholesterol deposits and making of enzymes and insulin.
  4. potassium: It helps to regulate fluid balance in our body.
  5. Iodine: It helps in the functioning of the thyroid gland. It prevents goiter and also burns fat.

Question 20.
What are roughages? mention the functions of roughages.
Answer:
Roughage foods are foods, which have high fiber content. It comes in different forms, functions of roughages.

  1. Dietary fiber is important because it provides volumes to the food, and this facilitates easy movement of materials in the alimentary canal
  2. Roughage’s had the ability to absorb water
  3. They combine with intentional wastes making them bulky.

Question 21.
Mention the importance of water.
Answer:
Importance of water is,

  1. Water constitutes about 55-75 percent of our body mass.
  2. It helps to maintain the health of every cell in the body
  3. It keeps the blood thin enough to flow thorough blood vessels.
  4. It helps to eliminate the wastes and excess materials
  5. Water regulates body temperature through sweating.
  6. Water helps digestion an prevents constipation.
  7. It helps to carry nutrients and oxygen to the cells.

Question 22.
What do you mean by ORS?
Answer:
ORS is the short form of oral hydration solution. Which is given to the patients suffering form cholera, acute diarrhea etc.

Question 23.
Write the preparation of ORS.
Answer:
ORS is prepared by adding 2 spoons of sugar 4 spoon of common salt and ‘A spoon of sodium bicarbonate in one liter of boiled and cooled water.

Question 24.
Write the test for proteins.
Answer:
Take about 5 ml of the solution in a test tube add 5-6 drops of biuret solution, wait for a while, do not heat. A color change from blue to pink indicates the presence of proteins matter in the solution.

Question 25.
Write the test for starch
Answer:
Take a small quantity of the given foodstuff in a dish. Add 2-3 drops of iodine solution. Note the color change if any, the appearance if a blue-black color indicates the presence of starch.

Question 26.
Athletes and sportspeople after an intense activity eat glucose. Give reason
Answer:
Person with intense activity needs more carbohydrates to release energy. Glucose is the simplest form of carbohydrate which is easily absorbable.

Question 27.
We must take carbohydrates in moderate quantities. give a reason.
Answer:
We must take carbohydrates moderate quantity because excess glucose can add to our weight.

Question 28.
Why is water essential to our bodies?
Answer:
The human body can last weeks without food but not without water. Water is essential for the human body If you do not drink enough water regularly there is some increased risk of kidney stones dehydration urinary tract infection in women. If urination stops due to dehydration the body cannot remove toxic waste products. It extreme cases may result in death.

KSEEB Solutions for Class 8 Science

Leave a Comment