Synapses: The junction points between the two neuron are called synapses. It is the junction between the axon of one neuron and the dendrite of next neuron . At the synapse, the axon and the dendrite do not touch each other, there is a small gap between the two. The message passes from one neuron on to other neuron through synapse by a chemical (neurotransmitter).
Reflex action: The responses (actions) which are immediate and do not need processing by the brain are called Reflex actions. In other words, reflex action is an involuntary action performed by a muscle, a gland or an organ under the direction of spinal cord in response to the stimulus.
Pathway of reflex action (sneezing)
Cells of nervous tissues are called neurons. Each neuron cell consists of a irregular cell body. From the surface of cell body fine processes arise called dendrites. A long process called axon also arise from the cell body. Sometimes axon is covered by one or two sheath. Then it is called medullated nerve fibre.
The dendrites receive the message or impulses from other neuron or organs. The axon conducts the impulses. The axon also form synapse junction with the dendrites of other neurons.
Fig. Nerve cell with medullated nerve fibre
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