I: | In a neuron, Nissl’s granules are present in dendrites as well as cell body |
II: | Unmyelinated neurons in peripheral neural system are not enclosed by a Schwann cell |
Statement I: | Depolarisation of axonal membrane is due to influx of sodium ions. |
Statement II: | Repolarisation of axonal membrane is due to efflux of sodium ions. |
When neuron is resting, which of the following is false with respect to that
1. | It is not conducting any impulse |
2. | Axonal membrane is more permeable to potassium ions |
3. | Axonal membrane won't allow any flow of sodium ions across it |
4. | Membrane is impermeable to negatively charged proteins |
I: | Myelinated nerve fibres |
II: | Unmyelinated nerve fibres |
Which of the following minerals reduces the excitability of nerves and muscles?
1. Potassium
2. Sodium
3. Magnesium
4. Manganese
Identify the correct statement regarding the sections of the spinal cord shown in the given diagram:
I: | A and D are part of the grey mater |
II: | B is motor and C is sensory |
1. | Only I | 2. | Only II |
3. | Both I and II | 4. | Neither I nor II |
1. | Diffusion of sodium to the inside of the cell. |
2. | Diffusion of sodium to the outside of the cell. |
3. | Diffusion of potassium to the outside of the cell. |
4. | Diffusion of potassium to the inside of the cell. |
Assertion(A): | The resting axonal membrane is more permeable to potassium ions than sodium ions |
Reason(R): | Potassium is the principal cation in the intracellular fluid. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False and (R) is True. |