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Science 7th Std, , 10. Respiration in Organisms, , 1. Why does an athlete breathe faster and deeper than usual after, finishing the race?, , A: When the athlete runs in the race, his body needs more energy. In, order to get extra energy, the athlete breathes faster and also takes,, deep breaths. Because more oxygen is supplied to our cells, it speeds, up the breakdown of food and more energy is released., , 2. List the similarities and differences between aerobic and, anaerobic respiration., , A: Similarities: 1. In both, food (glucose) is broken down., , 2. In both processes, energy is released., 3. Both take place in the cells., , Differences:, , Aerobic respiration Anaerobic respiration, , (a) It takes place in the presence (a) It takes place in the absence, of oxygen. of oxygen., , (b) More energy is released (b) Less energy is released in this, in this process. process, , (c) Glucose is broken down (c) Glucose is not broken, completely. completely, , (d) Carbon dioxide, water vapour, (d) Alcohol, lactic acid,carbon, and energy are formed dioxide and energy are formed., , 3. Why do we often sneeze when we inhale a lot of dust-laden air’, , A: The air around us contains various types of unwanted particles such, , as smoke, dust, pollen along with different gases. When we inhale,, dust particles get trapped in the hair present in our nasal cavity. This, causes irritation in the lining of the cavity. This results in sneezing., Sneezing expels the dust particles and other foreign particles from, the inhaled air and a dust-free, clean air enters our body.
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Take three test — tubes. Fill 3/4th of each with water. I abel th, A, B and C. Keep a snail in test-tube A, a water disni in m, test-tube B, and in C keep snail and plant both, which test-tube, , would have the highest concentration of CO?, Test Tube A will have the highest concentration of CO . This is, because test tube A contains snail, snail is an organism sheat breathes, , in O7 and breathes out CO,, Hence CO, concentration is found in, test tube A., , Test tube B contains a water plant, which takes in ‘CO, for food, synthesis and gives out O>. Hence, more O, concentration is found, in test tube B., , Test tube C contains both a snail and a plant, the co, produced by, the snail is utilized by the plant for its food synthesis and the O2, released by the plant is utilized by the snail for respiration., Therefore, test tube A has the highest concentration of co,, , Additional Important Questions and Answers., , 1., , A:, , >, , >, , Define cellular respiration. Where it takes place?, The process of breakdown of food in the cell with the release of, energy is called cellular respiration. It takes place in the cells of all, , organisms., Define aerobic and anaerobic respiration., , The breakdown of glucose occurs in the presence of oxygen or use, of oxygen is called aerobic respiration. Food can also be break down, , without using oxygen or in the absence of oxygen is called anaerobic, respiration., , What are Yeasts? Name its use., Yeasts are single-celled organisms. They respire anaerobically and, , during this process yield alcohol. It is used to make wine and beer,, yeasts are anaerobes.
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>>, , >a, , as, , >n, , How muscle cramps occur?, The muscle cramps occur when muscle cells respire anaerobically., , The partial breakdown of glucose produces lactic acid. The, , accumulation of lactic acid causes muscle cramps., , How do you get relief from muscle cramps?, , We should take hot water or massage treatment where muscle cramps, of blood., , occur. This hot water or massage improves the circulation, As a result, the supply of oxygen increases, it completes breakdown, of lactic acid into carbon dioxide and water. If there is no lactic, , acid, no muscle cramps., , Define exhalation and inhalation. ., The taking of air rich in oxygen into the body is called inhalation, , and giving out of air rich in carbon dioxide is known as, exhalation., , Define the breathing rate:, The number of times a person breathes in a minute is termed as thc, , breathing rate., Draw a neat diagram and label the parts of the Human, , Respiratory System.
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9. How do we breathe? or explain the mechanism of breathing in, , human beings., , A: Wetake air through our nostrils, when we inhale air., our nostrils into the nasal cavity. From the nasal cavity, the air reaches, our lungs through the windpipe. Lungs are present in the chest cavity., This cavity is surrounded by ribs on the sides. A large muscular, sheet is called diaphragm forms the floor of the chest cavity. During, inhalation, ribs move up and outwards and the diaphragm moves, down, this movement increases space in our chest cavity and air, rushes into the lungs. The lungs get filled with air, During exhalation,, ribs move down and inwards, while the diaphragm moves up to its, former position. This reduces the size of the chest cavity and the air, , is pushed out of the lungs., , It passes through, , 10. Write a neat diagram of fish showing breathing organs., , , , Breathing organs, in fish
