In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it.Read the Statement carefully and mark the correct answer-

Assertion(A): Upper and lower surfaces of a dicotyledonous leaves have different colour.

Reason (R): Dicotyledonous leaves are directed vertically upwards.

a)
Both Assertion and Reason are true and Reason is the correct explanation of Assertion.

b)
Assertion is true but Reason is false.

c)
Both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

d)
Both Assertion and Reason are false.

Correct answer is option 'B'. Can you explain this answer?

Question

In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it.Read the Statement carefully and mark the correct answer-

Assertion(A): Upper and lower surfaces of a dicotyledonous leaves have different colour.

Reason (R): Dicotyledonous leaves are directed vertically upwards.

a)
Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
b)
Assertion is true but Reason is false.
c)
Both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
d)
Both Assertion and Reason are false.

Correct answer is option 'B'. Can you explain this answer?

Answer

Leaves are directed vertically upwards is the characteristic feature of monocots     if suppose  the leaves of dicots are directed vertically upwards the  both surfaces of leaves should  be in same color

Answer

Dicotyledons are not isobilateral in nature like monocots means not having same no. of stomata on both sides that's why due to more no. of stomata on upper side it has darker green colour than lower side

Answer

C

Answer

Explanation:

The correct answer is option 'B' - Assertion is true but Reason is false.

Assertion (A): Upper and lower surfaces of a dicotyledonous leaves have different colour.
Reason (R): Dicotyledonous leaves are directed vertically upwards.

Explanation:
Assertion (A): Upper and lower surfaces of a dicotyledonous leaves have different colour.
The assertion is true. Dicotyledonous leaves have different colors on their upper and lower surfaces. This can be observed by looking at a dicot leaf under a microscope or by observing it in natural light. The upper surface of dicot leaves is typically darker in color, while the lower surface is lighter. This difference in color is due to the presence of different pigments on the two surfaces. The upper surface usually contains more chlorophyll, which gives it a darker green color, while the lower surface contains fewer chlorophyll and other pigments, resulting in a lighter color.

Reason (R): Dicotyledonous leaves are directed vertically upwards.
The reason is false. The direction in which dicotyledonous leaves are oriented does not determine the difference in color between their upper and lower surfaces. The color difference is primarily due to the variation in pigments present on the two surfaces, not their orientation. Dicotyledonous leaves can be oriented in various directions depending on factors such as light availability, air flow, and plant growth patterns. Some leaves may be directed vertically upwards, while others may be oriented horizontally or even vertically downwards. Therefore, the reason provided does not correctly explain the assertion.

In conclusion, while the assertion is true that dicotyledonous leaves have different colors on their upper and lower surfaces, the reason provided is false as the color difference is not determined by the orientation of the leaves. Hence, option 'B' - Assertion is true but Reason is false is the correct answer.

Answer

Option b

Answer

Elementary biology  u5 / 125

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