Advertisements
Advertisements
प्रश्न
Give function of astrocytes in nervous system.
Advertisements
उत्तर
Astrocytes have varied roles in the brain, secretion and absorption of neural transmitter and maintenance of blood-brain barrier BBB. They also regulate the transmission of electrical impulses with the brain.
संबंधित प्रश्न
Explain the following process:
Transmission of a nerve impulse across a chemical synapse
A person is showing symptoms like increased BMR, heart rate, pulse rate, blood pressure and deposition of fats in eye sockets. Name the disease he is suffering from.
Sketch and label formation of typical spinal nerve.
Complete the flowchart of the process of conduction of nerve impulses.
| Application of stimulus on a resting nerve |
| ⇓ |
| Permeability of membrane changes |
| ⇓ |
| ______________________________ |
| ⇓ |
| Positive ions inside axon increases |
| ⇓ |
| ________________________________ |
| ⇓ |
| Polarity reverses and depolarisation takes place |
| ⇓ |
| Repolarisation - potassium gates open |
| ⇓ |
| ______________________________ |
| ⇓ |
| ______________________________ |
| ⇓ |
| Axoplasm becomes negatively charged and ECF becomes positive |
Match the Column - I with Column - II:
| Column I | Column II | ||
| i. | P - wave | p. | Depolarisation of ventricles |
| ii. | QRS complex | q. | Repolarisation of ventricles |
| iii. | T - wave | r. | Coronary ischemia |
| s. | Development of atria | ||
| t. | Repolarisation of atria |
Neurotransmitters are removed from synaptic cleft by ____________ after transmission of impulse.
Which of the following situations is responsible for resting membrane potential?
Potential difference across resting membrane is negative. This is due to differential distribution of the following ions ______.
Resting membrane potential is maintained by ______.
Complete the statement by choosing appropriate match among the following -
| a. Resting potential | i. Chemicals involved in the transmission of impulses at synapses. |
| b. Nerve impulse | ii. Gap between the pre synaptic and post synaptic neurons |
| c. Synaptic cleft | iii. Electrical potential difference across the resting neural membrane |
| d. Neurotransmitters | iv. An electrical wave like response of a neuron to a stimulation |
