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 |
I: | Myelinated nerve fibres |
II: | Unmyelinated nerve fibres |
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. |
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 |
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 |
Which of the following minerals reduces the excitability of nerves and muscles?
1. Potassium
2. Sodium
3. Magnesium
4. Manganese
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. |