Worksheet Solutions: Food and its Components | General Knowledge Encyclopedia - Class 8 PDF Download

Section A: Multiple Choice Questions (MCQs)

Q1: Which of the following nutrients is an excellent source of energy for the body?
(a) Proteins
(b) Vitamins
(c) Fats
(d) Fiber

Ans: (c)
Explanation: Fats are an excellent source of energy for the body. When broken down, fats provide more than twice the amount of energy (calories) per gram compared to carbohydrates and proteins. They play a crucial role in energy storage and utilization.

Q2: Which of the following nutrients is needed for the growth and repair of body tissues?
(a) Carbohydrates
(b) Proteins
(c) Minerals
(d) Water

Ans: (b)
Explanation: Proteins are essential for the growth and repair of body tissues. They are made up of amino acids, which are the building blocks of the body. Proteins are involved in various functions, including the repair and maintenance of tissues, enzymes production, and supporting the immune system.

Q3: Which of the following is not a water-soluble vitamin?
(a) Vitamin C
(b) Vitamin B12
(c) Vitamin A
(d) Folate

Ans: (c)
Explanation: Vitamins can be classified as water-soluble (dissolves in water) or fat-soluble (dissolves in fat). Vitamin A is not a water-soluble vitamin; it is a fat-soluble vitamin. Water-soluble vitamins include Vitamin C, Vitamin B12, and Folate, as they dissolve in water and are not stored in the body to the same extent as fat-soluble vitamins.

Q4: Which of the following minerals is essential for the formation of hemoglobin?
(a) Iron
(b) Calcium
(c) Sodium
(d) Potassium

Ans: (a)
Explanation: Iron is essential for the formation of hemoglobin, the protein in red blood cells responsible for carrying oxygen throughout the body. Without sufficient iron, the body cannot produce enough healthy red blood cells, leading to a condition called anemia.

Q5: Which of the following macronutrients is an essential component of cell membranes?
(a) Carbohydrates
(b) Proteins
(c) Fats
(d) Fiber

Ans: (c)
Explanation: Fats are an essential component of cell membranes. Cell membranes are made up of a lipid bilayer, which consists of various types of fats (such as phospholipids and cholesterol). Fats play a crucial role in maintaining cell structure, function, and integrity.

Q6: Which of the following nutrients is an antioxidant?
(a) Calcium
(b) Vitamin D
(c) Vitamin E
(d) Sodium

Ans: (c)
Explanation: Vitamin E is an antioxidant. Antioxidants are substances that help neutralize harmful free radicals in the body, which can cause damage to cells and contribute to various diseases. Vitamin E helps protect cells from oxidative stress and is found in various foods like nuts, seeds, and vegetable oils.

Q7: Which of the following is an example of a complete protein?
(a) Rice
(b) Lentils
(c) Eggs
(d) Corn

Ans: (c) Eggs
Explanation: Eggs are an example of a complete protein. A complete protein contains all nine essential amino acids that the body cannot produce on its own. Eggs are a high-quality protein source as they provide all these essential amino acids in sufficient amounts.

Q8: Which of the following vitamins is necessary for proper blood clotting?
(a) Vitamin A
(b) Vitamin C
(c) Vitamin K
(d) Vitamin B12

Ans: (c) Vitamin K
Explanation: Vitamin K is necessary for proper blood clotting. It plays a key role in the coagulation process, helping to form blood clots to stop bleeding when there is an injury. Vitamin K is essential for maintaining healthy bones as well.

Q9: Which of the following food sources is rich in omega-3 fatty acids?
(a) Olive oil
(b) Avocado
(c) Salmon
(d) White bread

Ans: (c)
Explanation: Salmon is a food source that is rich in omega-3 fatty acids. Omega-3 fatty acids are a type of polyunsaturated fat that has been associated with various health benefits, including heart health and reducing inflammation.

Q10: Which of the following is not a function of dietary fiber?
(a) Promotes bowel regularity
(b) Lowers cholesterol levels
(c) Provides quick energy
(d) Supports healthy digestion

Ans: (c)
Explanation: Dietary fiber does not provide quick energy to the body. Unlike carbohydrates, which are broken down into glucose and used as a primary source of energy, dietary fiber cannot be digested by the body. Instead, it passes through the digestive system largely intact and has various health benefits, including promoting bowel regularity, lowering cholesterol levels, and supporting healthy digestion.

Section B: True or False

Q1: Carbohydrates are the body's primary source of energy.

Ans: True
Explanation: Carbohydrates are the body's primary source of energy. They are broken down into glucose, which is used by cells for energy.

Q2: Proteins are made up of amino acids.

Ans: True
Explanation: Proteins are made up of amino acids. Amino acids are the building blocks of proteins, and there are 20 different amino acids that can combine in various ways to form different proteins.

Q3: Fats are essential for the absorption of fat-soluble vitamins.

Ans: True
Explanation: Fats are essential for the absorption of fat-soluble vitamins (such as Vitamins A, D, E, and K). These vitamins require dietary fats for proper absorption in the digestive tract.

Q4: Vitamins and minerals are macronutrients.

Ans: False
Explanation: Vitamins and minerals are not macronutrients. Macronutrients are nutrients that are required by the body in large amounts, such as carbohydrates, proteins, fats, and water. Vitamins and minerals are micronutrients, which are required in smaller amounts but are still essential for various physiological functions.

Q5: Water is considered a macronutrient.

Ans: True
Explanation: Water is considered a macronutrient. It is essential for life and is required in relatively large amounts by the body for various physiological processes.

Section C: Fill in the Blanks

Q1: _______ is a complex carbohydrate found in grains, fruits, and vegetables.

Ans: Starch
Explanation: Starch is a polysaccharide, which is a type of complex carbohydrate. It serves as a storage form of glucose in plants and is an important source of energy for humans.

Q2: _______ is the process of breaking down food into smaller components for digestion.

Ans: Digestion
Explanation: Digestion is the process by which large, complex food molecules are broken down into smaller, simpler molecules that can be absorbed and utilized by the body.

Q3: _______ is an essential mineral for building strong bones and teeth.

Ans: Calcium
Explanation: Calcium is a crucial mineral for bone and teeth formation. It is also involved in muscle function, nerve transmission, and various other physiological processes.

Q4: _______ is a type of fat that is generally solid at room temperature.

Ans: Saturated fat
Explanation: Saturated fats are fats in which all available carbon bonds are saturated with hydrogen atoms. They tend to be solid at room temperature and are commonly found in animal products and some plant oils.

Q5: _______ is the main component of plant cell walls and is not digestible by humans.

Ans: Cellulose
Explanation: Cellulose is a type of dietary fiber and is the main component of plant cell walls. While it provides structural support to plants, humans lack the necessary enzymes to digest cellulose fully. However, it still plays a crucial role in promoting healthy digestion and bowel movements.