Question

The calcium ion at is to__. . chemical synapses chemical synapses neuron cell body; depolarize the axon terminal of the presynaptic cell neuron membrane; bind to neurotransmitter receptors on the postsynaptic cell chemical synapses; cause fusion of synaptic vesicles with the plasma membrane of the axon terminal electrical synapses; Interfere with IPSPs in the postsynaptic cell chemical synapses; repolarize the axon terminal of the postsynaptic cel

Answer 1

1. The answer is C.

After depolarization of the neurons, the voltage-gated Ca²⁺ channels open and allow Ca²⁺ ions to enter the cell. Entry of Ca2+ ion triggers the fusion of the synaptic vesicle with the presynaptic nerve terminal which causes the release of neurotransmitter in the synaptic cleft and hence neurotransmission take place.

2. The answer is D.

collateral ganglia are sympathetic ganglia present between present between paraventral ganglia and the target organs.

3. The answer is C.

when a neuron is stimulated above its threshold it causes the generation of action potential. The action potential is the change in the membrane potential of the neurons due to the opening of voltage-gated Na+ and K+ channels.

4. The answer is c.

Nicotinic gated channels are the ligand-gated channels. These channels open in response to ligand binding and allow Na+, K+ ions to pass through the membrane. They don't always lead to the generation of action potential. An action potential is generated only when the stimulus is above the threshold.

5. the answer is B.

The hypothalamus plays many important functions like regulation of body temperature, controlling appetite, emotions etc. Hypothalamus also links the nervous system to endocrine system and helps in the regulation of various metabolic and other activities of the autonomic nervous system.