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The given paragraph describes the restin...

The given paragraph describes the resting state of a nerve fiber.
When a neuron is resting , the axonal membrane is comparatively.....P........to potassium ions `(K^+)` and .....Q.... to sodium ions `(Na^+)` Similarly, the membrane is .....R....to negatively charged proteins present in the axoplasm .contains high concentration of ........s....... and ......T........P, Q, R ,S and are respectively

A

More permeable , nearly impermeable impermeable , `K^(+)` , proteins

B

Less permeable , nearly impermeable impermeable , `K^(+)` , proteins

C

More permeable , nearly impermeable less permeable , `Na^(+)K^(+)`

D

less permeable , highly permeable impermeable , `K^(+),Ca_(2)^(+)`

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To solve the question regarding the resting state of a nerve fiber, we need to fill in the blanks P, Q, R, S, and T based on the properties of the axonal membrane and the concentration of ions and proteins. ### Step-by-Step Solution: 1. **Understanding the Resting State of a Neuron**: - When a neuron is at rest, it has a specific distribution of ions across its membrane. This is crucial for the generation of action potentials. 2. **Analyzing the Permeability of the Membrane**: - The axonal membrane is more permeable to potassium ions (K⁺) than to sodium ions (Na⁺). This is because there are more open potassium channels than sodium channels in the resting state. - Therefore, for **P**, we can conclude that the membrane is **"more permeable"** to potassium ions. 3. **Sodium Ion Permeability**: - The axonal membrane is nearly impermeable to sodium ions (Na⁺) during the resting state. This is due to the lower number of sodium channels compared to potassium channels. - Thus, for **Q**, we can fill in **"nearly impermeable"** to sodium ions. 4. **Negatively Charged Proteins**: - The membrane is impermeable to negatively charged proteins present in the axoplasm. These proteins are large and cannot pass through the membrane. - Therefore, for **R**, we can write **"impermeable"** to negatively charged proteins. 5. **Concentration of Ions and Proteins**: - The resting state of the neuron has a high concentration of potassium ions (K⁺) inside the axoplasm and a high concentration of negatively charged proteins. - For **S**, we can fill in **"K⁺"** for potassium ions. - For **T**, we can fill in **"negatively charged proteins"**. ### Final Answers: - P: More permeable - Q: Nearly impermeable - R: Impermeable - S: K⁺ - T: Negatively charged proteins
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