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A : Sharpest vision is iin fovea centra...

A : Sharpest vision is iin fovea centralis.
R : The relationship of receptor to bipolar cells to ganglion cells is `1 : 1 : 1` within fovea centralis .

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).

C

If Assertion is true statement but Reason is false, then mark (3).

D

If both Assertion and Reason are false statements, then mark (4).

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion-reasoning question, we need to analyze both statements provided: ### Step 1: Analyze the Assertion The assertion states: "Sharpest vision is in fovea centralis." - The fovea centralis is a small pit located in the center of the retina, specifically in a region called the macula luteum. - This area is known for having the highest concentration of cone cells, which are responsible for color vision and visual acuity. - Since the fovea contains only cone cells and no rod cells, it is specialized for sharp vision, making this assertion true. ### Step 2: Analyze the Reason The reason states: "The relationship of receptor to bipolar cells to ganglion cells is 1:1:1 within fovea centralis." - In the fovea centralis, each cone cell connects directly to a single bipolar cell, which in turn connects to a single ganglion cell. - This 1:1:1 ratio is crucial for sharp vision because it allows for precise transmission of visual information from the photoreceptors (cone cells) to the brain via ganglion cells. - This statement is also true, as it accurately describes the neural pathway in the fovea centralis. ### Step 3: Determine the Relationship Between Assertion and Reason - Both the assertion and the reason are true. - The reason provides a correct explanation for the assertion because the unique arrangement of cells in the fovea centralis (1:1:1 ratio) directly contributes to its ability to provide the sharpest vision. ### Conclusion Both the assertion and the reason are true, and the reason correctly explains the assertion. ### Final Answer - **Assertion (A)**: True - **Reason (R)**: True - **Conclusion**: Both A and R are true, and R is the correct explanation for A. ---
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