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 |
Column I | Column II | ||
A | Sensory neurons | P | carry signals from the CNS to effectors (muscles or glands) |
B | Motor neurons | Q | connect sensory and motor neurons |
C | Interneurons | R | transmit signals from sensory receptors to the central nervous system |
A | B | C | |
1. | P | Q | R |
2. | Q | P | R |
3. | R | P | Q |
4. | R | Q | P |
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
1. | microglia | 2. | asrocytes |
3. | oligodendrocytes | 4. | Schwann cells |