Class 10 Science: Life Processes important questions
Life Processes is a chapter of Class 10 Science for the Andhra Pradesh State Board. These 32 questions are marked Very Important, Important or Practice, and each answer has been checked by our team. Use them to revise, not as a prediction of what will come in the exam.
Practice · 1 marks
1. Which valves are present between the atria and ventricles of the human heart?
The tricuspid valve (between the right atrium and right ventricle) and the bicuspid or mitral valve (between the left atrium and left ventricle). They stop blood flowing backwards.
Important · 2 marks
2. What are the important events that take place during photosynthesis?
1) Chlorophyll absorbs light energy. 2) Light energy is converted into chemical energy, and water molecules are split into hydrogen and oxygen. 3) Carbon dioxide is reduced to carbohydrates (glucose). 6CO₂ + 12H₂O → (sunlight, chlorophyll) C₆H₁₂O₆ + 6O₂ + 6H₂O
Important · 4 marks
3. Modes of respiration: cutaneous (skin) in earthworms; tracheal (tracheae) in cockroaches and grasshoppers; branchial (gills) in fish; pulmonary (lungs) in reptiles, birds and mammals. 1) What type of respiration occurs in a crow? 2) What are the respiratory organs of fish? 3) Which organisms show tracheal respiration? 4) What is the respiratory organ of an earthworm?
1) Pulmonary respiration (lungs), since a crow is a bird. 2) Gills. 3) Cockroaches and grasshoppers (insects). 4) The moist skin.
Important · 2 marks
4. Explain the digestion of fats in human beings.
Fats are digested in the small intestine. 1) Bile from the liver breaks large fat globules into tiny droplets (emulsification), giving more surface for enzymes. 2) Lipase from the pancreas breaks the emulsified fats down. 3) Glands in the intestinal wall secrete juice with more lipase, completing the digestion. Fats are finally converted into fatty acids and glycerol, which are absorbed.
Important · 4 marks
5. What are the components of the transport system in human beings, and what do they do?
1) Heart: a muscular pump that pushes blood around the body. 2) Blood vessels: arteries carry blood away from the heart; veins bring it back; thin capillaries connect them and exchange materials with the tissues. 3) Blood: plasma carries food, carbon dioxide and wastes; red blood cells carry oxygen (haemoglobin); white blood cells fight infection; platelets help blood clot. 4) Lymph: carries digested fats from the intestine and returns extra fluid from the tissues to the blood.
Important · 4 marks
6. Describe a neat labelled diagram of a nephron.
Draw a long tube starting with a cup-shaped Bowman's capsule, which holds a ball of capillaries called the glomerulus. The tube continues as the coiled proximal tubule, the U-shaped loop of Henle, the coiled distal tubule, and joins a collecting duct. Show the renal artery branch entering the glomerulus, and capillaries around the tubule. Labels: glomerulus, Bowman's capsule, proximal tubule, loop of Henle, distal tubule, collecting duct. The nephron is the basic filtration unit of the kidney.
Important · 4 marks
7. Give some suggestions to control high blood pressure and keep the heart healthy.
1) Eat less salt and less oily or fried food. 2) Eat more fruits, vegetables and whole grains. 3) Exercise regularly, for example walking, cycling or yoga. 4) Keep a healthy weight. 5) Avoid smoking and alcohol. 6) Manage stress and get enough sleep. 7) Get blood pressure checked regularly.
Very Important · 8 marks
8. Explain the lab activity to show that carbon dioxide is necessary for photosynthesis.
1) Take two healthy potted plants of the same size and keep them in the dark for three days to remove starch. 2) Place each on a glass plate and cover it with a bell jar. Under bell jar A, place a watch glass with potassium hydroxide (KOH), which absorbs carbon dioxide. Bell jar B has no KOH. 3) Seal the edges with vaseline and keep both in sunlight for a few hours. 4) Pluck a leaf from each plant and do the starch test: boil in water, then in alcohol, wash, and add iodine. Observation: the leaf from A (no CO₂) does not turn blue-black; the leaf from B turns blue-black. Conclusion: carbon dioxide is necessary for photosynthesis.
Practice · 1 marks
9. What is the basic filtration unit of the kidney?
The nephron.
Practice · 1 marks
10. Where does aerobic respiration take place in the cell?
In the mitochondria. Glucose is first broken down to pyruvate in the cytoplasm; then, in the presence of oxygen, pyruvate is broken down in the mitochondria into carbon dioxide and water, releasing a lot of energy.
Important · 2 marks
11. What questions would you ask if you met a gastroenterologist (a doctor for the digestive system)?
1) "What causes acidity and stomach ulcers, and how can they be prevented?" 2) "Which foods and habits keep the digestive system healthy?"
Important · 4 marks
12. Write the differences between single and double circulation.
Single circulation (e.g. fish): 1) Blood passes through the heart once in one complete cycle. 2) The heart has two chambers. 3) Blood goes from the heart to the gills, then directly to the body. Double circulation (e.g. birds and mammals): 1) Blood passes through the heart twice in one cycle: once to the lungs (pulmonary circulation) and once to the body (systemic circulation). 2) The heart has four chambers. 3) Oxygenated and deoxygenated blood do not mix, so the body gets a very efficient oxygen supply.
Important · 4 marks
13. Enzymes in digestion: Salivary amylase: buccal cavity, acts on carbohydrates. Pepsin: stomach, acts on proteins. Trypsin: pancreas, acts on proteins. Lipase: pancreas, acts on fats. 1) Which enzymes act on proteins? 2) Where is salivary amylase secreted? 3) Which enzymes does the pancreas secrete? 4) To which life process does this table belong?
1) Pepsin and trypsin. 2) In the buccal cavity (mouth), by the salivary glands. 3) Trypsin and lipase (pancreatic juice also contains amylase). 4) Nutrition (digestion).
Practice · 1 marks
14. Which digestive juice does not contain any enzymes?
Bile (secreted by the liver).
Important · 2 marks
15. Write the differences between bolus and chyme.
Bolus: the chewed food mixed with saliva in the mouth. It is a soft ball, slightly alkaline, and moves down the oesophagus. Chyme: the semi-liquid food in the stomach after mixing with gastric juice. It is acidic and passes into the small intestine.
Important · 2 marks
16. What are the consequences if the kidneys do not function properly?
Wastes such as urea build up in the blood and poison the body. The balance of water and salts is upset, causing swelling. If the kidneys fail, the blood must be cleaned artificially by dialysis, or a kidney transplant is needed.
Important · 2 marks
17. Ask two questions to a dentist to learn about the functions of teeth.
1) "What are the different types of teeth, and what job does each type do?" 2) "How does chewing food properly help digestion?"
Very Important · 8 marks
18. Explain how plants take up water through their roots.
1) Root cells take in ions (minerals) from the soil, so the concentration of ions inside the root is higher than in the soil. 2) Water from the soil therefore moves into the root hairs by osmosis. 3) This water passes from cell to cell into the xylem of the root, creating root pressure that pushes water upwards. 4) Transpiration from the leaves creates a suction (transpiration pull) that draws water up through the xylem from the roots to the leaves. This is the main force in tall plants, especially during the day.
Very Important · 8 marks
19. What experiment would you do to study anaerobic respiration?
1) Dissolve some sugar in water in a flask and add yeast. 2) Pour a layer of oil on top so that no air can reach the solution. 3) Close the flask with a cork carrying a bent delivery tube, and dip the other end in lime water in a test tube. 4) Leave it in a warm place for a few hours. Observation: bubbles pass into the lime water, which turns milky, and the flask smells of alcohol. Conclusion: yeast respires without oxygen (anaerobic respiration), producing carbon dioxide and ethanol.
Very Important · 8 marks
20. Explain the experiment that confirms the presence of starch in leaves.
1) Pluck a leaf from a plant that has been in sunlight for a few hours. 2) Boil it in water for a few minutes to soften it. 3) Boil it in alcohol, in a water bath, to remove the chlorophyll; the leaf turns pale. 4) Wash it in warm water, spread it in a petri dish and add a few drops of iodine solution. Observation: the leaf turns blue-black. Conclusion: the leaf contains starch, made by photosynthesis.
Practice · 1 marks
21. Expand ATP.
Adenosine triphosphate: the energy currency of the cell.
Practice · 1 marks
22. Forests have many plants and receive heavy rainfall. Excess water leaves plants through the stomata as vapour. How is transpiration related to the heavy rainfall?
Transpiration releases large amounts of water vapour into the air above forests. This makes the air humid; the vapour cools, condenses into clouds and falls as rain. So transpiration adds to the water cycle and increases rainfall in forest areas.
Important · 4 marks
23. Write the differences between arteries and veins.
Arteries: 1) Carry blood away from the heart to the organs. 2) Carry oxygenated blood (except the pulmonary artery). 3) Have thick, elastic walls, because the blood is under high pressure. 4) Have no valves, and are usually deep in the body. Veins: 1) Carry blood from the organs back to the heart. 2) Carry deoxygenated blood (except the pulmonary veins). 3) Have thin walls, because the blood pressure is low. 4) Have valves to stop blood flowing backwards, and many are near the surface.
Important · 4 marks
24. Describe a neat labelled diagram of a stoma.
Draw a stomatal pore in the middle with two kidney (bean)-shaped guard cells on either side. Show a nucleus and chloroplasts inside each guard cell, and the surrounding epidermal cells. Labels: stomatal pore, guard cells, chloroplast, nucleus, epidermal cells. The guard cells swell to open the pore and shrink to close it.
Important · 4 marks
25. Ravi and Raju are preparing for exams. Ravi thinks smoking relaxes him; Raju says yoga is better. Who is wrong, and how would you make him aware of the truth?
Ravi is wrong. Smoking damages the respiratory system: tar and harmful chemicals coat the lungs, destroy the tiny hairs that keep the airways clean, and cause coughing, bronchitis and lung cancer. Carbon monoxide in smoke reduces the oxygen the blood can carry, and nicotine is addictive. Yoga and breathing exercises improve lung capacity, reduce stress and improve concentration. Explain these facts to Ravi, show him health warnings, and encourage him to do yoga with Raju.
Very Important · 8 marks
26. Write the experimental procedure to show the action of saliva on starch.
Materials: two test tubes, starch solution, saliva, dilute iodine solution. 1) Take 1 mL of starch solution in each test tube, A and B. 2) Add 1 mL of saliva to tube A; leave tube B without saliva (control). 3) Keep both aside for 20–30 minutes. 4) Add a few drops of dilute iodine solution to each. Observation: B turns blue-black (starch present). A does not turn blue-black (or only faintly). Conclusion: saliva contains the enzyme salivary amylase, which breaks starch down into sugar.
Practice · 1 marks
27. Catalysts help chemical reactions happen. Digestive enzymes break down complex food molecules. How do you describe digestive enzymes chemically?
They are biological catalysts, and they are proteins. Examples: salivary amylase, pepsin, trypsin and lipase.
Important · 2 marks
28. Write two questions you would ask a doctor to learn more about haemoglobin.
1) "What is the normal haemoglobin level for a person of my age, and what happens if it is low (anaemia)?" 2) "Which foods help increase haemoglobin?" (Iron-rich foods such as green leafy vegetables, dates and jaggery.)
Important · 2 marks
29. What is fermentation? Where is it used?
Fermentation is the breakdown of glucose without oxygen (anaerobic respiration). In yeast it produces ethanol and carbon dioxide and releases a little energy: Glucose → ethanol + carbon dioxide + energy. Uses: making bread and cakes rise (the CO₂ makes them spongy), fermenting idli and dosa batter, making curd (with lactic acid bacteria), and producing alcohol and vinegar.
Important · 4 marks
30. Describe a well-labelled diagram of the human digestive system.
Show the alimentary canal from top to bottom: mouth with teeth and tongue → salivary glands → oesophagus (food pipe) → stomach → small intestine (long and coiled) → large intestine → rectum → anus. Show the glands attached: the liver (large, on the right, above the stomach) with the gall bladder, and the pancreas below the stomach. Labels: mouth, salivary glands, oesophagus, stomach, liver, gall bladder, pancreas, small intestine, large intestine, rectum, anus.
Important · 4 marks
31. Latha says plants do not excrete wastes. Raghu says plants manage most of their waste, besides excreting some. As group leader, how would you resolve this?
Raghu is right. Plants do excrete, in different ways: 1) Oxygen (in the day) and carbon dioxide (at night) leave through the stomata. 2) Excess water is removed by transpiration. 3) Some wastes are stored in cell vacuoles, or in leaves that later fall off. 4) Some are stored as resins and gums in old xylem. 5) Some wastes are excreted into the soil around the roots. Plants have no special excretory organs like animals, but they do get rid of wastes.
Very Important · 8 marks
32. Describe the experiment to show that chlorophyll is necessary for photosynthesis. Mention the materials used.
Materials: a potted plant with variegated leaves (e.g. croton or money plant), a beaker of water, alcohol, a test tube, a water bath, iodine solution and a petri dish. 1) Keep the plant in the dark for about three days to remove starch from the leaves (destarching). 2) Keep it in sunlight for about six hours. 3) Pluck a variegated leaf and note the green and non-green areas. 4) Boil the leaf in water for a few minutes, then in alcohol in a water bath to remove the chlorophyll. 5) Wash it, spread it in a petri dish and add iodine solution. Observation: only the parts that were green turn blue-black; the non-green parts do not. Conclusion: starch formed only where chlorophyll was present, so chlorophyll is necessary for photosynthesis.
Write these in your StudyNest notebook.
Scan the page into the app, and Nesto will explain each step. See the ₹60 notebook.