Frank Brothers Solutions for ICSE Class 9 Biology Chapter 15 Nutrition In Man

PAGE NO: 138

Question 1:
Answer:
Carbohydrates provide energy and warmth to our body.
These are the primary fuel source for our cells to perform daily activities. They are found in common foods like rice, wheat, and potatoes.
Teacher's Tip: Think of carbohydrates as the "petrol" that keeps your body's engine running.
Exam Tip: Use the phrase "energy-giving food" to describe carbohydrates for high scores.

Question 2:
Answer:
Sources of Vitamin C are Lemon and carrot and sources of Vitamin A are Green vegetables and egg yolk.
Vitamin C is essential for a strong immune system and healthy skin. Vitamin A is vital for maintaining good eyesight, especially in the dark.
Teacher's Tip: Remember "C" for Citrus fruits like lemons to find Vitamin C easily.
Exam Tip: List specific food items when asked for "sources" to show thorough knowledge.

Question 3:
Answer:
Vitamin C
This vitamin is water-soluble and helps in the healing of wounds. It is also found in abundance in Indian gooseberries (Amla).
Teacher's Tip: Scurvy can be prevented by eating plenty of Vitamin C.
Exam Tip: Always mention the specific vitamin name clearly in one-word answers.

Question 4:
Answer:
Pigs and crows
These animals are classified as omnivores because they have a varied diet. They play a crucial role in the ecosystem by eating different types of organic matter.
Teacher's Tip: Omnivores are like "all-rounders" in a cricket team; they can do everything!
Exam Tip: Provide two examples as shown in the textbook to ensure a complete answer.

Question 5:
Answer:
Carbohydrates
Sugar and starch are the two main forms of carbohydrates that we consume. Our body breaks them down into glucose for immediate energy.
Teacher's Tip: Foods that taste sweet or are starchy are usually high in carbohydrates.
Exam Tip: Remember that carbohydrates are the most abundant component in a balanced diet.

Question 6:
Answer:
Roughage
Roughage is the undigested fiber in our food that helps keep our digestive system clean. It adds bulk to the stool and prevents constipation.
Teacher's Tip: Think of roughage as a "broom" that sweeps your intestines clean.
Exam Tip: Define roughage as "dietary fiber" if you want to sound more scientific.

Question 7:
Answer:
Assimilation
This is the process where digested nutrients are actually used by the body's cells. It helps in building new tissues and providing energy for growth.
Teacher's Tip: Absorption puts food in the blood, but assimilation puts it to work in the cells.
Exam Tip: Distinguish between absorption and assimilation to avoid losing marks.

Question 8:
Answer:
Fats
Fats provide more than double the energy of carbohydrates but are stored for later use. They also help in protecting our internal organs like a cushion.
Teacher's Tip: Fats are your body's "energy bank" for emergencies.
Exam Tip: Mention that fats also help in the absorption of certain vitamins like A, D, E, and K.

Question 9:
Answer:
1. Carnivores are flesh-eating animals that eat other animals. Example - Snakes, Lion, tiger, vulture
2. Omnivores are animals that feed on both animals and plants. Example - crows, certain bears.
3. Scavenger is any animal that feeds on refuse and other decaying organic matter. Example - vultures, dung beetle.
These categories help us understand the different feeding habits of animals in nature. Each group has a specific role in maintaining the balance of the ecosystem.
Teacher's Tip: "Carn" means meat, "Omni" means all, and "Scavengers" are the nature's cleaners.
Exam Tip: Include at least two examples for each category for a higher score.

Question 10:
Answer:
(a) Autotrophs: They prepare their own food from simple inorganic raw materials. Example - Green plants
Heterotrophs: They depend on autotrophs for their food and are unable to synthesize their own food. Example - Animals
(b) Herbivore: These animals feed on plants. Example - Goat, Giraffe
Carnivore: These animals feed on other animals. Example - Lion, frog
(c) Assimilation: It involves utilization of absorbed food by different body cells.
Absorption: It is the process by which soluble digested food passes from alimentary canal into the blood and lymph through intestinal villi.
These comparisons show the fundamental differences in how life forms obtain and use energy. Knowing these terms is the foundation of understanding biology.
Teacher's Tip: "Auto" means self, so autotrophs are self-sufficient food makers.
Exam Tip: When comparing, always align the points of difference clearly in rows or a table.

Question 11:
Answer:
Food is a mixture of nutritive substances which when taken and incorporated into the body tissues provide materials for energy, repair, growth, reproduction, regulation of life processes and resistance to diseases.
Food is the essential "fuel" and "building blocks" for every living organism. It contains different nutrients like proteins and vitamins that our body needs every day.
Teacher's Tip: Think of food as a "multi-tool" that fixes, fuels, and protects your body.
Exam Tip: List the functions like "repair" and "growth" clearly to show a complete definition.

Question 12:
Answer:
Proteins are used in the synthesis of new protoplasm to be utilized in growth and tissue repair. Hence they are called body building foods.
Proteins are responsible for making muscles, skin, and even your hair. They act as the "bricks" that build and fix our body's structure.
Teacher's Tip: Drink milk or eat pulses to get the "bricks" your body needs to grow tall.
Exam Tip: Use the term "body building foods" specifically when describing proteins.

Question 13:
Answer:
(a) Night-blindness
(b) Protein
(c) Vitamin D
(d) Insectivore
These terms identify specific health issues and nutritional categories. For example, Vitamin D is often called the "sunshine vitamin" because our skin makes it in sunlight.
Teacher's Tip: Match the deficiency to the nutrient: Lack of A = Night-blindness.
Exam Tip: Double-check the spelling of scientific terms like "Insectivore."

Question 14:
Answer:
(a) False
(b) True
(c) True
(d) False
(e) True
True or false questions test your basic concepts about what constitutes a healthy diet. It is important to know that while vitamins are needed in small amounts, they are still vital.
Teacher's Tip: If a statement says "all" or "none," read it very carefully as it might be a trick.
Exam Tip: For "False" statements, practice writing the correct version to better your understanding.

PAGE NO: 139

Question 15:
Answer:
Water is necessary for our body because:
1. Water acts as solvent for many organic and inorganic compounds
2. Water facilitates the movement of food materials, waste products and other chemical substances in the cytoplasm and circulatory process.
3. It plays an important role in regulating body temperature and osmotic pressure of the body fluids.
4. Water serves as good medium for various metabolic reactions.
Our bodies are mostly made of water, and it is needed for almost every chemical reaction inside us. Without water, our blood could not flow and our cells could not stay alive.
Teacher's Tip: Water is the "universal solvent" that helps carry things around inside you.
Exam Tip: List at least three distinct points to score full marks for the importance of water.

Question 16:
Answer:
The undigested fibrous material present in the food is called roughage. Raw vegetables, and bran are examples of roughage
Roughage might not give us energy, but it is necessary for a healthy gut. Eating whole grains and fresh salads is the best way to get enough of it.
Teacher's Tip: Whole fruit is better than fruit juice because it has all the roughage!
Exam Tip: Always provide examples like "bran" or "raw vegetables" when defining roughage.

Question 17:
Answer:
(a) energy
(b) glycogen
(c) fatty acid, glycerol
(d) sucrose, maltose
These answers fill in the specific molecules our body uses or creates from food. For instance, extra sugar is stored in our liver as a substance called glycogen.
Teacher's Tip: Fatty acids and glycerol are the building blocks of fats.
Exam Tip: Learn the pairs: Fats break down into fatty acids and glycerol.

Question 18:
Answer:
1. The condition where people become weak and sick due to insufficient and unbalanced diet is referred to as malnutrition.
2. Saprozoic nutrition refers to nutrition in which animals feed on dead or decaying matter.
3. Vitamins are organic compounds regularly required in minute quantities in the diet for normal metabolism, health and growth.
Malnutrition can happen even if you eat a lot, if you aren't eating the right nutrients. Vitamins act like "spark plugs" that help start important processes in your body.
Teacher's Tip: "Minute quantities" means very tiny amounts, like a pinch of salt in a big pot.
Exam Tip: Define vitamins as "organic compounds" to get technical accuracy in your answer.

Question 19:
Answer:
(a) Milk
(b) Sugarcane
(c) Plants
(d) Yellow and green vegetables
This list shows where we get our daily nutrients from the natural world. Milk is often called a "complete food" because it contains almost everything we need.
Teacher's Tip: Eat a rainbow of vegetables to make sure you get all the different vitamins.
Exam Tip: Identify "milk" as a primary source for both proteins and minerals like calcium.

Question 20:
Answer:
1. Kwashiorkor develops in children whose diet is deficient in proteins even if sufficient carbohydrates and fats are consumed. This disease is common among infants and children up to 3 years old. The symptoms of Kwashiorkor include reduced body weight, slurred growth, protruding belly and thin legs.
2. Marasmus is a form of prolonged protein energy malnutrition. It affects infants under one year of age. The symptoms of Marasmus include irreversible muscle degeneration, dry, wrinkled skin, prominent ribs and thin legs.
These diseases show how vital proteins and energy are for young children to grow healthy. While Kwashiorkor is mostly about missing protein, Marasmus is about missing almost everything.
Teacher's Tip: "Marasmus" sounds like "Muscle loss" because the body looks very wasted.
Exam Tip: Distinguish between the ages (under 1 year for Marasmus vs. up to 3 years for Kwashiorkor).

Question 21:
Answer:
1. Deficiency of iron leads to anaemia.
2. Deficiency of iodine leads to goitre.
Minerals like iron and iodine are needed in small amounts but are very important. Iron helps your blood carry oxygen, and iodine helps your thyroid gland work properly.
Teacher's Tip: Spinach is great for iron, and iodized salt gives you the iodine you need.
Exam Tip: Memorize the mineral and its specific deficiency disease as a pair.

Question 22:
Answer:
1. (a) 500 gm
2. (d) food
3. (b) rice
4. (b) Carrot
5. (a) A, D and E
6. (d) K
7. (c) Protein
8. (a) C
These multiple-choice answers summarize the key facts about a balanced diet and vitamins. For example, Vitamin K is famous for helping your blood clot when you get a cut.
Teacher's Tip: Vitamin "K" is for "Koagulation" (Clotting).
Exam Tip: When answering MCQs, read all options (a to d) before making your final choice.