Photosynthesis assertion reason questions for Class 10 ICSE
1.) Assertion (A): Chlorophyll is essential for photosynthesis.
Reason (R): Chlorophyll absorbs light energy and converts it into chemical energy.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (c) A is True and R is False
2.) Assertion (A): Photosynthesis takes place in the chloroplasts.
Reason (R): Chloroplasts contain pigments that capture light energy for the photosynthetic process.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
3.) Assertion (A): Oxygen is produced during the light-dependent reactions of photosynthesis.
Reason (R): Water molecules are split, and oxygen is released as a byproduct.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
4.) Assertion (A): Photosynthesis is an endothermic process.
Reason (R): It requires light energy to convert carbon dioxide and water into glucose.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
5.) Assertion (A): The Calvin cycle is a part of the light-dependent reactions in photosynthesis.
Reason (R): The Calvin cycle is responsible for the synthesis of ATP and NADPH.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
6.) Assertion (A): Photosynthesis occurs in both plants and animals.
Reason (R): Some algae and bacteria can perform photosynthesis.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
7.) Assertion (A): Photosynthesis is a process that converts carbon dioxide into oxygen.
Reason (R): Oxygen is a byproduct of the breakdown of glucose during photosynthesis.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (c) A is True and R is False
8.) Assertion (A): Light-independent reactions occur in the thylakoid membrane.
Reason (R): Thylakoid membranes contain pigments that capture light energy.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
9.) Assertion (A): The primary pigment involved in photosynthesis is chlorophyll a.
Reason (R): Chlorophyll a absorbs light most effectively in the red and blue regions of the electromagnetic spectrum.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
10.) Assertion (A): Photosynthesis is an anabolic process.
Reason (R): It involves the synthesis of complex organic molecules from simpler substances.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
11.) Assertion (A): Photosynthesis is the reverse process of cellular respiration.
Reason (R): Cellular respiration releases carbon dioxide and water, while photosynthesis uses them to produce glucose.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
12.) Assertion (A): Photosynthesis occurs in the stroma of the chloroplast.
Reason (R): The stroma is the site of the Calvin cycle, where glucose is synthesized.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
13.) Assertion (A): Light-dependent reactions produce ATP and NADPH.
Reason (R): These molecules are used in the Calvin cycle to fix carbon dioxide.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (c) A is True and R is False
14.) Assertion (A): Photosystem II comes before Photosystem I in the light-dependent reactions.
Reason (R): Photosystem II absorbs light at a shorter wavelength than Photosystem I.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (d) A is False and R is True
15.) Assertion (A): RuBisCO is an enzyme involved in the Calvin cycle.
Reason (R): RuBisCO catalyzes the fixation of carbon dioxide during photosynthesis.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
16.) Assertion (A): Photosynthesis occurs in the presence of oxygen.
Reason (R): Oxygen is a necessary reactant for the synthesis of glucose.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
17.) Assertion (A): Photosynthesis is limited by the availability of light, carbon dioxide, and water.
Reason (R): These factors are essential for the proper functioning of the light-dependent and light-independent reactions.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
18.) Assertion (A): The oxygen released during photosynthesis comes from the carbon dioxide molecule.
Reason (R): Oxygen is a byproduct of the reduction of carbon dioxide during photosynthesis.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
19.) Assertion (A): Photosynthesis is an exothermic process.
Reason (R): It releases energy stored in glucose molecules.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
- Assertion (A): Photosynthesis is more efficient in red and blue light compared to green light.
Reason (R): Chlorophyll absorbs red and blue light most effectively.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
21.) Assertion (A): The Calvin cycle occurs in the thylakoid membrane.
Reason (R): The thylakoid membrane is the site of the light-dependent reactions.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
- )Assertion (A): The primary purpose of photosynthesis is to produce oxygen for respiration.
Reason (R): Oxygen produced during photosynthesis is essential for the breakdown of glucose in cellular respiration.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
23.) Assertion (A): The thylakoid membrane is involved in the synthesis of glucose.
Reason (R): The thylakoid membrane contains enzymes for the conversion of glucose.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
24.) Assertion (A): Photosynthesis is more efficient in C4 plants compared to C3 plants.
Reason (R): C4 plants have a unique mechanism to concentrate carbon dioxide around the enzyme RuBisCO.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (c) A is True and R is False
25.) Assertion (A): Photosynthesis is the only process by which plants obtain energy.
Reason (R): Plants rely solely on sunlight for energy production.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
26.) Assertion (A): Photosynthesis and cellular respiration are interdependent processes.
Reason (R): The oxygen produced in photosynthesis is used in cellular respiration, and the carbon dioxide produced in respiration is used in photosynthesis.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
27.) Assertion (A): The rate of photosynthesis is influenced by temperature.
Reason (R): Enzymes involved in photosynthesis have optimal temperature ranges for activity.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
- ) Assertion (A): Photosynthesis produces glucose, which is used as a source of energy.
Reason (R): Glucose is broken down in the mitochondria during cellular respiration to release energy.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
29.) Assertion (A): Photosynthesis is a continuous process occurring throughout the day and night.
Reason (R): The light-dependent reactions occur only during the day, while the light-independent reactions can occur at any time.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (d) A is False and R is True
- ) Assertion (A): The main product of the light-dependent reactions is glucose.
Reason (R): Glucose is synthesized in the thylakoid membrane.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (b) Both A and R are False
- ) Assertion (A): Photosynthesis is limited by the availability of nitrogen.
Reason (R): Nitrogen is a crucial component of chlorophyll, the pigment responsible for capturing light energy.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
32.) Assertion (A): CAM plants are adapted to arid conditions.
Reason (R): CAM plants open stomata at night to reduce water loss during the day.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (c) A is True and R is False
- ) Assertion (A): The main purpose of the light-dependent reactions is to produce ATP.
Reason (R): ATP is utilized in the Calvin cycle for the synthesis of glucose.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
34.) Assertion (A): Photosynthesis is an example of a redox reaction.
Reason (R): During photosynthesis, water is oxidized to produce oxygen, and carbon dioxide is reduced to produce glucose.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True
35.) Assertion (A): Chloroplasts contain multiple membranes.
Reason (R): Thylakoid membranes are surrounded by the outer and inner chloroplast membranes.
(a) Both A and R are True
(b) Both A and R are False
(c) A is True and R is False
(d) A is False and R is True
Answer: (a) Both A and R are True