Life Process MCQs
86. Name the green pigment present in the leaves of a plant.
Answer/Explanation
Answer:
Explanation: Chlorophyll.
87. In the experiment “Light is essential for photosynthesis”, why does the uncovered part of the leaf turn blue-black after putting iodine solution? [HOTS]
Answer/Explanation
Answer:
Explanation:
Starch is produced in the uncovered part of the leaf due to photosynthesis which turns blue-black in presence of iodine solution.
88. Name a unicellular organism which uses cilia to move food particles into its mouth.
Answer/Explanation
Answer:
Explanation: Paramoecium.
89. Mention how organisms like bread moulds and mushrooms obtain their food.
Answer/Explanation
Answer:
Explanation:
Organisms like bread moulds and mushrooms break down the food materials outside the body and then absorb it.
90. Classify the followings as saprotrophs or parasites:
leech, yeast, mushroom
Answer/Explanation
Answer:
Explanation:
Saprotrophs : yeast, mushroom
Parasites : leech
91. Which enzyme present in saliva breaks down starch?
Answer/Explanation
Answer:
Explanation:
The saliva contains an enzyme called salivary amylase that breaks down starch.
92. Why does our mouth ‘water’ when we see or eat a food which we really like?
Answer/Explanation
Answer:
Explanation:
Due to the production of saliva by the salivary glands in the mouth.
93. Why does bread taste sweet on mastication?
Answer/Explanation
Answer:
Explanation:
Salivary amylase act on starch of food and change it into a sweet sugar called maltose.
94. Which pancreatic enzyme is effective in digesting proteins?
Answer/Explanation
Answer:
Explanation:
Trypsin is the pancreatic enzyme which is effective in digesting proteins.
95. Where does digestion of fat take place in our body?
Answer/Explanation
Answer:
Explanation:
Digestion of fat takes place in the small intestine of our body.
96. What is alimentary canal?
Answer/Explanation
Answer:
Explanation:
It is a long tube extending from mouth to anus in which digestion and absorption of food takes place.
97. Define peristaltic movement? [DoE]
Answer/Explanation
Answer:
Explanation:
Peristaltic movement is defined as contraction and relaxation of muscles in the food pipe . which brings food down the pipe into the stomach.
98. Name the longest part of the alimentary canal.
Answer/Explanation
Answer:
Explanation:
Small intestine.
99. What is emulsification? [DoE]
Answer/Explanation
Answer:
Explanation:
Breakdown of large gloubule fats into smaller fats droplets is known as emulsification.
100. What is the name given to the biological catalyst which speed up the chemical reactions taking place in cells.
Answer/Explanation
Answer:
Explanation: Enzymes.
101. Name the muscle which regulates the exit of food from stomach to small intestine.
Answer/Explanation
Answer:
Explanation: Sphincter muscle.
102. How does the acidic medium in the small intestine is converted into alkaline for pancreatic enzymes?
Answer/Explanation
Answer:
Explanation: By the action of bile juice secreted by liver.
103. In which part of alimentary canal digestion does not occur?
Answer/Explanation
Answer:
Explanation: Large intestine
104. Name the structure which regulates the exit of waste material.
Answer/Explanation
Answer:
Explanation: Anal sphincter.
105. State the basic difference between the process of respiration and photosynthesis.
Answer/Explanation
Answer:
Explanation:
Respiration uses O2 and releases CO2 but in photosynthesis, CO2 is used and O2 is released.
106. Name the pigment present in human which aids in respiration.
Answer/Explanation
Answer:
Explanation: Haemoglobin.
107. Give one point which is common for both aerobic and anaerobic respiration.
Answer/Explanation
Answer:
Explanation:
In both aerobic and anaerobic respiration, the chemical used is glucose.
108. Why is anaerobic respiration less efficient?
Answer/Explanation
Answer:
Explanation:
Anaerobic respiration is the incomplete breakdown of glucose and produces less energy, so it is less efficient.
Fill in the Blanks
1. The exit of food from the stomach is regulated by a ………. muscle.
2. ………. is the longest part of the alimentary canal.
3. The process of breakdown of glucose, (a six-carbon molecule) into pyruvate, (a three-carbon molecule), takes place in the ………. .
4. ………. is the site of the complete digestion of carbohydrates, proteins and fats.
5. Breaking of pyruvate using oxygen takes place in the ………. .
6. Rings of cartilage are present in the wind pipe to ensure that the ………. .
7. The blood has ………. cells which plug the leakage in the vessels by helping to clot the blood at the point of injury.
8. ………. transports products of photosynthesis from the leaves to other parts of the plant.
Answers
1. sphincter
2. Small intestine
3. cytoplasm
4. Small intestine
5. mitochondria
6. air-passage does not collapse
7. platelet
8. phloem