Class 10 Science Chapter 6 Life Processes

 

Extra Questions for Class 10 Science Chapter 6 Life Processes

Extra Questions Based On Nutrition:

Q.1. State the photosynthetic reaction and where does it occur?

Answer: The process of photosynthesis occurs in green parts of a plant, basically leaves. The presence of chlorophyll (green pigment) is necessary for photosynthesis to occur and chlorophyll is present in leaves as green dots.

The process of the photosynthetic process is depicted here:

Q.2. Identify the mode of nutrition where sunlight is used along with CO2 and water to prepare food.

Answer: In photosynthesis, sunlight is used along with water, CO2 and chlorophyll to prepare food. The mode of nutrition here is autotrophic. Example of autotrophic organisms is green plants that make their own food and do not depend on any organism for their nutrition.

Q.3. What are pseudopodia?

Answer: Pseudopodia (singular: pseudopodium) are temporary finger-like elongated protrusions of cell surface of unicellular organisms (Amoeba) used for feeding and locomotion. They are formed by cytoplasmic streaming (streaming movement of cytoplasm). It is also called as false foot.

Q.4. Which organelle acts as the site of photosynthesis?

Answer: The chloroplast acts as the site of photosynthesis. It is a cell organelle that is covered by a double membrane and it contains chlorophyll. It is present in green tissues of plants, especially leaves. Chloroplasts absorb sunlight to conduct photosynthesis.

Q.5. What type of nutrition occurs in fungi?

Answer: Fungi are heterotrophic organisms. They depend on other organisms to obtain nutrition. They show the saprobic mode of nutrition or saprotrophic nutrition. They break down the food material outside their body by secreting digestive enzymes and absorb nutrition from it.

Q.6. Name the raw materials which are essential to carry out the process of photosynthesis in plants.

Answer: The raw materials needed to carry out photosynthesis are water (absorbed through roots), CO2 (diffused in from the air through stomata). In addition to these, chlorophyll (green pigment present in chloroplasts) and sunlight are also required. Without these materials, photosynthesis cannot occur.

Q.7. Explain the term ingestion.

Answer: Ingestion refers to the consumption of food, water and other substances through the mouth into the gut. Ingestion is a general term used for taking in any substance into the digestive system.

Q.8. Where is bile juice produced?

Answer: Bile juice (dark green-yellow pigment) is produced by the liver. It helps in the digestion of lipids (fats) in small intestine. It emulsifies (breaks down) larger fat globules into smaller ones so that enzymes can act efficiently on fat globules.

Q.9. What happens to extra glucose or carbohydrate in an animal body?

Answer: In an animal body, extra glucose or carbohydrate is stored in the liver as well as in skeletal muscles in the form of glycogen. Glucose is converted to glycogen (starch-like carbohydrate) in liver. When the body is in need of energy, glycogen is converted back into glucose.

Q.10. What is mainly digested by stomach of man?

Answer: The digestion of proteins occurs in the stomach. It is facilitated by digestive enzymes (pepsin, hydrochloric acid). HCl provides acidic medium while pepsin acts on proteins and breaks them into smaller peptides.

Q.11. Name two molecules produced by the digestion of starch and fat respectively.

Answer: The digestion of starch (complex carbohydrate) produces glucose and maltose (simple sugars).
Fats are broken down to produce molecules of glycerol and fatty acids.

Q.12. Which feature(s) help the plants to make food by the process of photosynthesis?

Answer: The leaves containing the green pigment chlorophyll (present in chloroplast) helps the plant to perform photosynthesis by trapping light energy. The plant absorbs CO2 through stomata and reduces it to glucose. The presence of chloroplasts and stomata helps the plants to make food.

Q.13. Write the difference between nutrition in plants and animals.

Answer: Plants and animals have a completely different mode of nutrition. Plants are autotrophic organisms that are capable of making their own food by performing photosynthesis using 2 raw materials (water + CO2).
They need light energy to make their own food. Plants do not depend on any organism to obtain nutrition. On the other hand, animals are heterotrophic organisms that depend on other organisms (plants and other animals) to fulfill their nutrition requirements. They cannot make their own food.

Q.14. How do parasitic organisms derive their nutrition?

Answer: Parasitic organisms like tapeworms, leeches, orchids, etc., obtain nutrition from other living organisms (plants or animals) called as host, without killing them. Parasites may live on the outside or inside the body of its host. They cause harm to the body of the host.

Extra Questions Based On Life Processes

Q.15. Name one accessory pigment and one essential pigment in photosynthetic plants.

Answer. Accessory pigment – Carotene/Xanthophyll
Essential pigment – Chlorophyll.

Q.16. What is the mode of nutrition in human beings?

Answer. Holozoic nutrition.

Q.17. Where does digestion of fat take place in our body?

Answer. Digestion of fat takes place in the small intestine of our body.

Q.18. What would be the consequences of deficiency of hemoglobin in your body?

Answer. The deficiency of hemoglobin in our body is called anemia. In anemia, the blood is
unable to carry the sufficient amount of oxygen required by the body. So, respiration would be
less and less energy will be available to the body. The hemoglobin deficient person will feel
weak, pale, lethargic and will be unable to perform heavy physical work.

Q.19. Give one reason why multicellular organisms require special organs for exchange of gases between their body and their environment.

Answer. In unicellular organisms the entire body of the organism is in contact with the environment hence exchange of materials can take place but, in multicellular organisms the entire body of the organism is not in contact with the environment and hence simple diffusion is not helpful.

Q.20. What will happen to a plant if its xylem is removed?

Answer. Xylem in plant transports water and dissolved mineral nutrients from the roots to all parts of the vascular plant. So, if xylem is removed from the plant, the water and mineral supply to the plant will stop and therefore, the plant will die.

Q.21. State any one difference between autotrophic and heterotrophic modes of nutrition.

Answer. In autotrophic nutrition, organisms obtain their food from inorganic substances. In heterotrophic nutrition, organisms derive their food from organic substances.

Q.22. Name the process in plants where water is lost as water vapour.

Answer. Transpiration is the process when plants loose water as vapour.

Q.23. Name the green dot like structures in some cells observed by a student when a leaf peel was viewed under a microscope. What is this green colour due to?

Answer. The green dot-like structures in some cells observed by a student when a leaf peel is viewed under a microscope are chloroplasts. The green colour is due to the presence of green pigment, chlorophyll.

Q.24. Mention the raw materials required for photosynthesis.

Answer. The following raw materials are required for photosynthesis:
(i) Carbon Dioxide: Plants get CO2 from atmosphere through stomata.
(ii)Water: Plants absorb water from soil through roots and transport to leaves.
(iii) Sunlight: Sunlight, which is absorbed by the chlorophyll and other green parts of the plant.

Q.25. State the basic difference between the process of respiration and photosynthesis.

Answer. Respiration uses O2 and releases CO2 but in photosynthesis, CO2 is used and O2 is released

Q.26. What is ‘translocation’ in plants?

Answer. Translocation is the movement of soluble materials, products of photosynthesis from
leaves to other tissues throughout the plant.

Q.27. Name the component of blood that helps in the formation of blood clot in the event of a cut.

Answer. Platelets help in clotting of blood in the event of a cut.

Q.28. Specify two conditions in which photo-respiration may take place in green plants.

Answer. Two conditions in which photorespiration may take place in green plants are: (i) High concentration of oxygen and (ii) High temperature.

Q.29. Mention how organisms like bread moulds and mushrooms obtain their food.

Answer. Organisms like bread moulds and mushrooms breakdown the food materials outside the body and then absorb the nutrients of the bread.

Q.30. What advantage over an aquatic organism does a terrestrial organism have with regard to obtaining oxygen for respiration?

Answer. The amount of oxygen dissolved in water is very low, as compared to amount of oxygen in air. Thus, terrestrial organism has to make less efforts to obtain oxygen than an aquatic organism to obtain oxygen for respiration.

Q.31. Name the two ways in which glucose is oxidised to provide energy in various organisms.

Answer. The two ways in which glucose is oxidised to provide energy in various organisms are aerobic respiration pathway which uses oxygen to break-down glucose completely into carbon dioxide and water and some use other pathways that do not involve oxygen which is called anaerobic respiration pathway.

Q.32. In the experiment “Light is essential for photosynthesis”, why does the uncovered part of the leaf turn blue-black after putting iodine solution?

Answer. Starch is produced in the uncovered part of the leaf because it is exposed to sunlight allowing it to photosynthesize, which turns blue-black in presence of iodine solution.