EDULABZ INTERNATIONAL 7 LIFE PROCESSES

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1 7 LIFE PROCESSES I. Multiple choice questions: Tick ( ) the correct choice. 1. Which one is an insectivorous plant? (a) Lichens (b) Venus fly-trap (c) Mushrooms (d) Yeast Ans. (b) 2. Two different organisms living together and both benefiting from each other, are known as (a) saprophytic (b) symbiotic (c) parasitic (d) heterotrophs Ans. (b) 3. The green colour pigment in the leaves is (a) chlorophyll (b) anthocyanin (c) protoplast (d) chloroplast Ans. (a) 4. Tiny pores on the lower surface of leaf are (a) lamina (b) stomata (c) chlorophyll (d) leaf stalk Ans. (b) 5. Sugar and starch are (a) proteins (b) fats (c) carbohydrates (d) vitamins Ans. (c) 6. When iodine turns blue-black, it shows the presence of (a) protins (b) carbohydrates (c) fats (d) vitamins Ans. (b) 7. Calcium and phosphorus are required for (a) healthy teeth and bones (b) long and black hair (c) forming haemoglobin (d) healthy nerves and muscles Ans. (a) 8. Iodine is found in (a) seafood (b) milk (c) banana (d) spinach Ans. (a) 9. Which of the following is needed in smallest quantity by our body? (a) Carbohydrates (b) Proteins (c) Fats (d) Vitamins Ans. (d) Biology Class VII 1 Question Bank

2 II. 10. We need roughage in our food because it (a) gives energy (b) builts body (c) helps metabolism (d) prevents constipation Ans. (d) 11. Which of the following food items is rich in carbohydrate? (a) Cabbage (b) Rice (c) Gram (d) Mushroom Ans. (b) 12. Which of the following is a water-soluble vitamin? (a) Vitamin C (b) Vitamin A (c) Vitamin D (d) None Ans. (a) 13. The leaves appear yellow when grown in (a) light (b) dark (c) at high temperature (d) at low temperature Ans. (b) 14. Which gas is a raw material for photosynthesis? (a) CO 2 (b) N 2 (c) O 2 (d) CO Ans. (a) 15. Dodder (cuscuta) is a (a) Parasite (b) Saprophyte (c) Insectivorous plant (d) Leguminous plant Ans. (a) Fill in the blanks. 1. The body-building function of food is related to the presence of Energy-giving foods are carbohydrates and Pulses are rich in The main function of carbohydrates is to provide... to the body. 5. Deficiency of iodine leads to... in man. 6. Food energy is measured in units called Deficiency of vitamin C causes a disease called During photosynthesis, the gas released is The presence of starch can be tested by using.... Biology Class VII 2 Question Bank 2

3 10. On testing with iodine, starch turn... in colour. 11. The small pores present on the leaves through which carbon dioxide enters the leaf are called Deficiency of... causes chlorosis of young leaves. 13. Mushroom is a Proteins are made up of smaller units called are fat-soluble vitamins. 16. In..., animals or plants live together for mutual benefit. 17. Calcium is required for the Fruits are rich in Iron is required for the formation of the substance When there is a deficiency of..., fruits do not ripen easily. Ans. 1. Proteins 2. Fats 3. Proteins 4. Energy 5. Goitre 6. Calories 7. Scurvy 8. Oxygen 9. Iodine solution 10. Blue-black 11. Stomata 12. Magnesium 13. Saprophyte 14. Amino acids 15. A, D, E & K 16. Symbiosis 17. Growth of bone and teeth 18. Carbohydrate 19. Haemoglobin 20. Phosphorus III. Which of the following statements are true (T) and which ones are false (F)? Mark T or F. 1. You use more calories when you swim than when you walk. 2. A diet that supplies enough calories is a balanced diet. 3. Iron is an important part of blood. 4. Potato is rich in carbohydrates. 5. Iodine solution is used to test the presence of fats in the food. 6. If there were no plants, the amount of oxygen in the air would have gone on decreasing. 7. Photosynthesis occurs only in chlorophyll containing parts of the plant. 8. Overeating is good in order to stay fit. 9. Amino acid is also known as vitamin C. 10. Balanced diet of a boy is richer than that of a girl of same age group. 11. A food chain is impossible without green plants. 12. Rhizobium fixes nitrogen in leguminous plant. Biology Class VII 3 Question Bank

4 13. Light and dark reactions are the parts of photosynthesis. 14. Chlorophyll contains iron. 15. Carbohydrates are building blocks of our body. 16. Iodised salt is rich in iodine. 17. Bread, maggi and pizza are rich in carbohydrates. 18. Fats are the essential units of proteins. 19. Vitamin B complex is a fat soluble vitamin. 20. Deficiency of iron, causes anaemia. Ans. 1. T 2. T 3. T 4. T 5. F 6. T 7. T 8. F 9. F 10. T 11. T 12. T 13. T 14. F 15. F 16. T 17. T 18. F 19. F 20. T IV. A. Match the items in Column A with those in Column B. Column A Column B 1. Tiny pores in leaves (a) Leaf 2. Needed by plants to make food (b) Stomata 3. A plant s food factory (c) Water, sunlight 4. Living on another organisms and (d) Symbiosis derive food from them 5. Two different organisms live together (e) Parasitic and both are mutually beneficial. Ans. 1. (b) 2. (c) 3. (a) 4. (e) 5. (d) B. Suppose we compare the leaf with a factory, match the items in column A with those in column B. Column A Column B Leaf Factory 1. Cells in the leaf (a) Raw materials 2. Chloroplast (b) Power 3. Sunlight (c) Machinery 4. Oxygen and water (d) End product 5. CO 2 and water (e) By product 6. Glucose (f) Work room Ans. 1. (c) 2. (f) 3. (b) 4. (a) 5. (e) 6. (d) Biology Class VII 4 Question Bank 4

5 V. Find the odd one out. Give reasons. 1. Proteins, carbohydrates, fats, vitamins, amino acids Ans. Amino Reason: All are the nutrients except amino acids. Amino acids are the smaller units of protein. 2. Rice, wheat, soyabean, noodles, bread Ans. Soyabean Reason: All are the sources of carbohydrates except soyabean which is a rich source of protein. 3. Meat, egg, beans, spinach, milk Ans. Spinach Reason: All are the rich sources of protein except spinach which is the source of iron. 4. Butter, cucumber, oil, ghee, almonds Ans. Cucumber Reason: All are the sources of fat except cucumber. 5. Iron, sodium, potassium, iodine, vitamin A Ans. Vitamin A Reason: All are minerals except vitamin A. VI. Define the following: 1. Food Ans. Food. Food are the substances from which an organism derives energy and other components for growth and maintenance. 2. Nutrition Ans. Nutrition. Nutrition is the process of consumption and utilisation of food. 3. Nutrient Ans. Nutrient. Nutrients are the components of food. They provide all necessary material for growth and maintence development. 4. Autotrophic nutrition Ans. Autotrophic nutrition. This type of nutrition is found in green plants. Green plants can synthesise their own food with the help of chlorophyll in presence of sunlight. Green plants are thus called autotrophs. Biology Class VII 5 Question Bank

6 5. Carnivores Ans. Carnivores. The animals which feed on the flesh of other animals are called carnivores, e.g., tiger, lion and dog. 6. Omnivores Ans. Omnivores. The animals which feed on plants as well as animals are called omnivores, e.g., human beings, cockroach. 7. Herbivores Ans. Herbivores. The animals which feed only on plants and plant products are called herbivores, e.g., goat, buffalo. 8. Insectivorous plants Ans. Insectivorous plants. These are green plants and prepare their own food by photosynthesis. But, to complete the demand of nitrogen they depend on insects, e.g. pitcher plant, venus flytrap. 9. Symbiotic nutrition Ans. Symbiotic nutrition. In this type of nutrition, two different organisms live together and both are mutually beneficial to each other. For example: In lichen, algal and fungal partners live together. 10. Saprophytic nutrition Ans. Saprophytic nutrition. Many living organisms feed on dead and decaying organic matter. This type of nutrition is called saprophytic nutrition. Mushroom, yeast and many bacteria have saprophytic nutrition. VII. Name the following: 1. Energy-providing foods Ans. Energy-giving food: Carbohydrates & fats. 2. Growth-promoting foods Ans. Growth-promoting foods: Proteins. 3. Protective foods Ans. Protective foods: Vitamins and minerals. 4. Some food items that are rich in calcium. Ans. Milk, cheese, green leafy vegetables, eggs are some food items that are rich in calcium. Biology Class VII 6 Question Bank 6

7 5. Three sources of each of the following nutrients: (a) Carbohydrates (b) Fats (c) Proteins Ans. (a) Carbohydrates: Sources are wheat, maize, rice, etc. (b) Fats: Sources are butter, cheese, meat, etc. (c) Proteins: Sources are pulses, meat, egg, etc. 6. Diseases caused by the deficiency of (a) Vitamin A (b) Iron (c) Vitamin C (d) Iodine Ans. (a) Due to deficiency of vitamin A night-blindness occurs (b) Due to deficiency of iron anaemia occurs. (c) Due to deficiency of vitamin C, scurvy occurs. (d) Due to deficiency of iodine, goitre occurs. 7. Mineral supplied by the following foods (a) Seafood (b) Milk (c) Table salt Ans. (a) Seafood provides mineral iodine. (b) Milk provides mineral calcium. (c) Table salt provides mineral iodine. 8. The pigment which gives green colour to leaves. Ans. Chlorophyll gives green colour to the leaves. 9. Gas used in photosynthesis. Ans. CO 2 is used in photosynthesis. 10. One plant which can eat insects. Ans. Pitcher plant is an insectivorous plant. VIII. Complete the chart (Calories required by different class of individual): Individual Energy requirement 1. Man (moderately active) kcal 2. Woman (moderately active) kcal 3. Woman (pregnant) kcal 4. Boy (16-18 years) kcal 5. Girl (16-18 years) kcal Ans Biology Class VII 7 Question Bank

8 IX. Differentiate between the following terms. (i) Autotrophs and Heterotrophs Ans. Autotrophs Heterotrophs (1) All green plants are called (1) All animals including man autotrophs. and non-green plants are called heterotrophs. (2) Autotrophs derive their food (2) Heterotrophs derive their by a pigment called chloro- food from other organisms, phyll through a process directly or indirectly from called photosynthesis. plants. (3) Autotrophs are the producers (3) Heterotrophs are the conof food on the earth. sumers of food. (ii) Xylem and phloem Ans. Xylem Phloem (1) It is water-conducting (1) It is food-conducting tissue. tissue. (2) It is present in the wood. (2) It is present in the bark. (3) Xylem consists of several (3) Phloem consists of sieve different types of cells: fibre tubes, companion cells for support, parenchyma for and phloem parenchyma. storage and tracheary elements for the transports of water. (iii) Producers and Consumers Ans. Producers Consumers (1) Green plants are called (1) All animals are called conproducers because they sumers because they derive prepare their own food by their food from other CO 2 and H 2 O in presence organisms, directly or of sunlight. indirectly from plants. Biology Class VII 8 Question Bank 8

9 Producers Consumers (2) Producers are also called (2) Consumers are also called autotrophs. heterotrophs. (3) Producers are only green (3) Consumers are of three plants. types: Primary consumer, secondary consumer tertiary consumer. X. Answer the following. 1. List three functions of food. Ans. Three functions of food: (1) Food provides energy to perform various functions to sustain life. (2) Food is required for growth. (3) Food helps in the repair of damaged body parts. 2. Name the various components of food. Ans. We have seven nutrients in our food: (1) Carbohydrates (2) Fats (3) Protains (4) Mineral salts (5) Vitamins (6) Water (7) Roughage 3. What is roughage? How is it important for the body? Ans. Roughage are the fibres that has no nutritive value. But it prevents constipation and necessary for proper functioning of the digestive system. 4. Why is water essential for our bodies? Ans. Our 70 percent of body weight is due to water. Water is very essential for various functions of our body like transportation of substances, maintain a constant body temperature, etc. So, we must take 2-3 litres of water everyday. 5. What is a balanced diet? Ans. A diet which provides proper amount and proportion of calories, proteins, vitamins minerals, roughage and water to Biology Class VII 9 Question Bank

10 maintain a healthy body is called balanced diet. Balanced diet is essential for proper growth of our body. 6. What is obesity? Ans. Obesity is the condition in which excess fat has accumulated in the body. It is usually caused by consuming more food than is needed for energy. 7. Mention five good food habits. Ans. Five food habits for good health (i) We must take balanced diet according to age, health and occupation. (ii) Our utensils must be clean and free from dust and flies. (iii) We should avoid fried food as far as possible and consume simple digestible food. (iv) We should consume large quantities of clean filtered water and roughage to avoid constipation. (v) Eat cooked fresh food and chew well. 8. What are the average daily requirements of proteins in case of children and adults? Why do children need more proteins than adults? Ans. Children require more protein than adults because this age is growing age and children are also more active than adults. So, children require more energy. For adults, requirement of protein is 1 g for every 1 kg of body weight while children require 1.46 gm of every 1 kg of body weight. 9. Why should we include vitamins in our diet? Mention the sources of different vitamins. Ans. Vitamins are neither energy-giving nor body-building food but they are essential for normal working of the body. Sources of different vitamins are as follows: 1. Vitamin A. Sources are milk, butter, cheese, tomatoes, carrots and cod-liver oil. 2. Vitamin B-complex. Sources are milk, eggs, cheese, meat, liver, husk of cereals and pulses. Biology Class VII 10 Question Bank 10

11 3. Vitamin C. Sources are citrus fruits like orange, lemon, green vegetables and tomatoes. 4. Vitamin D. Sources are milk, yellow of egg, liver, fish liver oil, cod liver oil synthesisc under the skin in the presence of sunlight. 5. Vitamin K. Sources are green leafy vegetables like spinach, cabbage, etc. 10. Which one offers you more energy? (a) one large banana or 100 grams of grapes. (b) one egg or one teaspoon of butter. Ans. (a) One large banana gives more energy than 100 gm of grapes. [One large banana gives 100 calories, 100 gm of graphes gives 70 calories.] (b) One teaspoon butter gives more energy than one boiled egg [One teaspoon butter gives 100 calories, one boiled egg gives 75 calories.] 11. Which substances eaten by man have little or no nutrient value? Ans. Roughage is found in vegetables, fruits, beans and cereals. It has no nutritive value and necessary for proper functioning of the digestive system. 12. Why do living organisms need food? Ans. Living organisms need food for the following purposes. (1) For energy to do various functions to sustain life. (2) It is required for proper growth. (3) It is required for repair of damaged body parts like loss of blood and skin damage. (4) It protects from diseases and infection. (5) It maintains the chemical composition of cells. 13. Describe the role of chlorophyll in photosynthesis. Ans. Chlorophyll is present inside certain structures called chloroplasts. The trap energy from sunlight. Without chlorophyll, photosynthesis will not take place. Biology Class VII 11 Question Bank

12 14. Define nutrition. What are the various types of nutrition? Ans. Nutrition is the process by which living organism receives the food necessary for them to grow and be healthy. Basically, there are two modes of nutrition: [A] Autotrophic [B] Heterotrophic. [A] Autotrophic Nutrition. Green plants are called autotrophs because they can prepare their own food with the help of chlorophyll in presence of sunlight. The process by which green plants prepare their own food is called photosynthesis. [B] Heterotrophic Nutrition. All animals which can not make their own food show heterotrophic mode of nutrition. They derive their food from other organisms directly or indirectly from green plants. Heterotrophic animals can be of three types: (i) Herbivores. These are plant-eating animals, e.g., buffalo, goat and elephant. (ii) Carnivores. These animals eat other animals, e.g. tiger, lion and dog. (iii) Omnivores. These animals feed on plants as well as animals, e.g., humans, cockroach and crow. 15. Which part of the plant body takes in water? Ans. Root part of plant body takes in water. Upward movement of water occurs through channels, called xylem elements. 16. Where from does carbon dioxide enter a plant? Ans. Exchange of gases in plants takes place through stomata. 17. What is produced during photosynthesis? Ans. Carbohydrates and oxygen are the products of photosynthesis. 18. Mention of different factors affecting the rate of photosynthesis. Biology Class VII 12 Question Bank 12

13 Ans. There are many factors that affect the rate of photosynthesis. These are as follows: (i) Intensity of light. The more the intensity of light, the more will be the photosynthesis but up to a certain point. (ii) Availability of carbon dioxide. More concentration of carbon dioxide increases the rate of photosynthesis. (iii) Water availability. Less availability of water reduces the rate of photosynthesis. (iv) Temperature. Up to a certain temperature, the rate of photosynthesis increases. (v) Inorganic mineral ions. Sulphur, phosphorus, calcium, magnesium, potassium, chlorine, aluminium, boron, manganese, copper, zinc and chlorine are some inorganic elements which have different functions in the process of photosynthesis. Some of these elements are required in smaller quantities called micronutrients and some in larger quantities called macronutrients. 19. Describe the role of stomata in photosynthesis. Ans. Stomata play an important role in photosynthesis. The opening and closing of stomata is related to the photosynthetic activity in the leaves. Exchange of gases takes place through stomata, Stomata open during day and close during night. 20. How is food material transported from the leaves to other plant parts? Ans. Green plants prepare their food with the help of sunlight. This prepared food material is transported from leaves to other parts of plant through food channels, called phloem. 21. What are nutrients? Ans. The food which is eaten by the living organisms to perform various functions to sustain, life has nutrients. So, nutrients are the substances that a living organisms needs to live and grow. 22. Why does our body require nutrients? Ans. Our body requires nutrients because nutrients act as a fuel that Biology Class VII 13 Question Bank

14 allows the body for various functions like running jumping, walking and swimming. 23. List the main functions of carbohydrates, fats and proteins. Ans. Functions of carbohydrates, fats and proteins: (1) Carbohydrates are the nutrients that provide the body with its main source of energy. (2) Fats are the secondary source of energy. They provide twice the energy of carbohydrates. Fat is also stored in the body for future use. When our body needs food, it uses its stored fat. Stored fats also insulate and protect organs of the body. (3) Proteins are the nutrients that provide the body with materials for cell growth and repair. They are the main building material of cells. 24. How is starch different from complex sugar molecules? Ans. Complex sugar is made of two simple sugar molecules while starch is made up of many molecules of simple sugar. 25. How is the presence of proteins tested in a food item? Ans. Test for Protein. Take egg white in a test tube. Now add a few drops of dil. HNO 3 and heat it. It turns yellow. Now pour out the acid and add a few drops of Ammonium hydroxide (NH 4 OH). The colour of egg white turns reddish. 26. Name four food items which belong to the pulses and meat group. Ans. Pulses and meat are the rich sources of proteins. Egg, milk, cheese and fish are also belong to this group. 27. Name the water-soluble and fat-soluble vitamins. Ans. Fat-soluble vitamins are A, D, E, and K. Water-soluble vitamins are B and C. 28. What might happen if you do not consume a variety of food items? Ans. If we are not consuming a variety of food items then we will Biology Class VII 14 Question Bank 14

15 suffer from deficiency diseases which develop by not taking some particular nutrients in the food. 29. What might happen if you consume more calories than your body needs? Ans. If anyone is consuming more calories than their body needs that person gains weight. This condition is called obesity. 30. Is the balanced diet for a labourer and a child same? Justify your answer by giving reasons. Ans. Balanced diet is different for a labourer and a child. A labourer needs more carbohydrates and fats in his diet because they need more energy whereas a child must take more proteins, as they help in body building. 31. How do plants obtain their food? What is the raw material required to make food? Ans. Plants are called autotrophs because they make their own food by the process of photosynthesis. In this process, plants utilise CO 2 and H 2 O as a raw materials for the synthesis of food in presence of sunlight which is captured by the green pigment, chlorophyll. In a chemical reaction, CO 2 and H 2 O is converted to glucose and oxygen is released. Sunlight Carbon dioxide + Water Glucose + Oxygen Chlorophyll 32. What are insectivorous plants? How are they different from other green plants? Ans. Insectivorous plants are green plants and prepare their own food. But, to complete the demand of nitrogen they depend on insects, e.g., pitcher plant and venus flytrap. 33. Alcohol should not be heated in direct flame. Why? Ans. We should not heat alcohol directly on the flame because it may catch fire. 34. Name four important minerals present in our body. Ans. Calcium and phosphorus are required for strengthening of bones and teeth. Sodium and potassium are necessary for cell permeability mainly for nerve cell. Biology Class VII 15 Question Bank

16 35. Define food chain and food web. Ans. Food chain. A group of organisms in which there is a transfer of food energy through a series of repeated eating and being eaten. Food web. Food web is the system of many food chains that are linked with one another. In a food web a particular organism may feed at more than one trophic level. 36. A leaf of healthy plant kept in sunlight for one day and a leaf of healthy plant kept in the dark for two days were tested with iodine solution. What results would you expect? Ans. A leaf of healthy plant which is kept in the dark for two days will not show starch test with iodine solution. Because in dark, plant did not do photosynthesis, so no starch was formed. 37. How will you show that sunlight is necessary during photosynthesis? Ans. To show that light is necessary for photosynthesis. Take a potted plant and keep it in a dark room for two days. This is done to make the plant starch free. Now cover a leaf from both the sides with a black paper and keep the plant in sunlight. Now remove the leaf after 5 6 hours and test it for the presence of starch. The part of leaf which is not covered by black paper shows the starch test. 38. Do the plants need oxygen? If so, what is its source? Ans. Plants need oxygen for respiration and very little quantity of oxygen is also released from the photosynthesis. Oxygen is produced as a by product of photosynthesis, used up in the respiration. 39. Why is it necessary to place a plant in the dark before starting an experiment on photosynthesis? Ans. It is necessary to place a plant in the dark before starting an experiment on photosynthesis because it makes the plant starch free. Biology Class VII 16 Question Bank 16

17 40. What is the difference between chlorophyll and chloroplast? Ans. Chloroplast is a cell organelle while chlorophyll is a green pigment present in chloroplast. 41. Name some macronutrients and micronutrients needed by plants. Ans. Nitrogen, phosphorus, potassium, calcium, magnesium, carbon, hydrogen and iron are some macronutrients. Boron, manganese, copper, zinc and malybdenum are some micronutrients needed by the plants. **** Biology Class VII 17 Question Bank