Life Processes: Class 10 Science Q&A · Page 2
107 free answers on Life Processes (Science) for Class 10 students, across CBSE, ICSE and State boards.
Question & Answer
Questions
- ScienceClass 10CBSE
Why does absorption of digested food occur mainly in the small intestine?
Small intestine has specialized structures that facilitate absorption of digested food. Small intestine has number of folds that increase the area of absorption. Small intestine also has fingerlike projection called microvilli which are richly supplied by blood vessels.
- ScienceClass 10CBSE
What causes movement of food inside the alimentary canal?
Peristalsis is the process that cause movement of food inside the alimentary canal.
- ScienceClass 10CBSE
What is the significance of emulsification of fats?
Emulsification is a process of breakage of larger fats molecules into digestible fat globules. Emulsification aids action enzymes on fats by breaking larger fat molecules.
- ScienceClass 10CBSE
What will happen if mucus is not secreted by the gastric glands?
Soln: Mucus prevent inner lining of stomach from HCL. Mucus prevents drying of inner lining of the stomach. Mucus helps in easy movement of food particles through digestive system. If mucus is not secreted food will not easily moved through digestive system. HCL will damage the stomach lining and the digestion process will not take place.
- ScienceClass 10CBSE
Why is small intestine in herbivores longer than in carnivores?
Soln: Food of herbivores contains mostly cellulose. To digest cellulose herbivores need help of certain bacteria. In order to accommodate the microbes and to facilitate digestion of food herbivores has longer small intestine than carnivores.
- ScienceClass 10CBSE
What are the adaptations of leaf for photosynthesis?
Soln: Adaptation of leaf for photosynthesis are as follows Surface of leaf is flat to allow greater exposure of Presence of chlorophyll to trap sunlight Presence of stomata on the lower surface for easy transpiration
- ScienceClass 10CBSE
Differentiate between an artery and a vein.
Soln: Artery has thick walls whereas Veins has thin walls. Arteries carries blood away from the heart but veins carry blood to the heart. In arteries valves are absent and in veins they are present In arteries blood flows under pressure but in veins there will be no pressure.
- ScienceClass 10CBSE
Match the words of Column (A) with that of Column (B) Column A Column B Phloem (i) Excretion Nephron (ii) Translocation of food Veins (iii) Clotting of blood Platelets (iv) Deoxygenated blood
Soln: Column A Column B Phloem (ii) Translocation of food Nephron (i) Excretion Veins (iv) Deoxygenated blood Plat
- ScienceClass 10CBSE
How does aerobic respiration differ from anaerobic respiration?
Soln: Aerobic Respiration Anaerobic respiration Takes place in the presence of Oxygen Takes place in the absence of Oxygen Carbon-di-oxide and water are the end products Carbon-di-oxide and Lactic acid/ethanol are the end products </t
- ScienceClass 10CBSE
1. Leaves of a healthy potted plant were coated with vaseline. Will this plant remain healthy for long? Give reasons for your answer.
Coating Vaseline to the leaves of a healthy plants will clog its stomata pores and stops the respiration of plants and the plants dies.
- ScienceClass 10CBSE
1. What would happen if green plants disappear from earth?
Green plants are the sources of energy for all the heterotrophs on earth. Plants convert solar and chemical energy into viable food sources. If plants gets disappeared from the earth it lead to imbalance in the ecosystem and heterotrophs may die without food.
- ScienceClass 10CBSE
1. Is ‘nutrition’ a necessity for an organism? Discuss.
Nutrition is an absolute necessity for the organisms because nutrition provides energy for carrying out metabolic activities.
- ScienceClass 10CBSE
Differentiate between an autotroph and a heterotroph
Autotrophs Heterotrophs They can make their own food They cannot make their own food Ex: Plants and certain bacteria Ex: Animals, Fungi and protozoans
- ScienceClass 10CBSE
1. Why do fishes die when taken out of water?
Soln: Fishes can respire only by using dissolved oxygen. When we take fish out of water it cannot respire due to lack of dissolved oxygen and they die.
- ScienceClass 10CBSE
If a plant is releasing carbon dioxide and taking in oxygen during the day, does it mean that there is no photosynthesis occurring? Justify your answer.
If a plant is releasing carbon dioxide and taking in oxygen during the day means plant is respiring; it does not mean that there is no photosynthesis occurring in the plant. This is because Photosynthesis and respiration are two independent processes.
- ScienceClass 10CBSE
Two green plants are kept separately in oxygen free containers, one in the dark and the other in continuous light. Which one will live longer? Give reasons.
Plant kept in continuous light live longer because plats release CO2 during respiration. In case of plant kept in dark CO2 resulting in lack of oxygen and the plant will die earlier.
- ScienceClass 10CBSE
How do the guard cells regulate opening and closing of stomatal pores?
Opening of guard cells is facilitated by the entry of water inside guard cells. This make the guard cell become turgid. Closing of guard cells is facilitated by water coming out of guard cells. This will make the guard cells flaccid. Entry of water inside guard cells will make the cell turgid leading to the opening of stomata. Similarly cell become flaccid when water come out of guard cells, this leads to closing of the stomata.
- ScienceClass 10CBSE
All plants give out oxygen during day and carbon dioxide during night”. Do you agree with this statement? Give reason.
The statement is wrong because plants respire every time and expel out Carbon-di-oxide every time but they give out oxygen only in the day time as photosynthesis process can take place only in the presence of sunlight.
- ScienceClass 10CBSE
Name the following (a) The process in plants that links light energy with chemical energy (b) Organisms that can prepare their own food (c) The cell organelle where photosynthesis occurs (d) Cells that surround a stomatal pore (e) Organisms that cannot prepare their own food (f) An enzyme secreted from gastric glands in stomach that acts on proteins.
Photosynthesis Autotrophs Chloroplasts Guard cells Heterotrophs Pepsin
- ScienceClass 10CBSE
During deficiency of oxygen in tissues of human beings, pyruvic acid is converted into lactic acid in the (a) cytoplasm (b) chloroplast (c) mitochondria golgi body
Answer is (a) cytoplasm Explanation: When there is lack of oxygen Breakdown of Pyruvate takes place in cytoplasm of muscle cells leading to the formation of Lactic acid.