Question

Which of the following statement/s is true in case of synapse?
A. Neurotransmitters diffuse across the synapse (the gap) and bind with receptor molecules on the membrane of the next neuron.
B. Synapse is a small gap that occurs between the axon of one neuron and dendrite of the next neuron.
C. Nerve impulse reaches the synapse at the end of a neuron; it cannot pass directly to the next one.
D. All of the above

Answer 1

Hint:The synapse is generated by the membranes of the postsynaptic and the presynaptic neurons. Synapse is known as the functional junction between neurons.

Complete answer:
The cells of the nervous tissue are known as neurons. A neuron comprises a cell body with cytoplasm and a nucleus, dendrites, axon, and nerve endings. Axon is the single long part of a neuron. This transfers nerve impulses away from the cell body to the synapse. Dendrites are the short branched parts of a neuron. These are short fibers that have regularly branched and extended out of the cell body. According to the number of dendrites and axons, the neurons can be divided into 3 types. They are: multipolar, bipolar and unipolar. In a multipolar neuron, one axon and two or more dendrites are found. In bipolar neurons, one dendrite and one axon are present. In the unipolar neuron, the cell body is found with only one axon.
Nerve impulses can pass through certain junctions from one neuron to another. These junctions are known as the synapse. The synapse is generated by the membranes of the postsynaptic and the presynaptic neurons. So, the functional junction between neurons is called a synapse. Synapse is a small gap that occurs between the axon of one neuron and dendrite of the next neuron. Nerve impulse reaches the synapse at the end of a neuron; it cannot pass directly to the next one. One neuron sends a message to a target neuron in a synapse - another node. The bulk of synapses are organic, interacting by chemical messengers. Additional synapses are electric; ions pass directly through cells in these synapses. In a chemical synapse, the presynaptic neuron activates neurotransmitters by an action potential. These molecules bind to the postsynaptic cell receptors and make it more or less likely to induce action. Neurotransmitters diffuse across the synapse and bind with receptor molecules on the membrane of the next neuron.

Thus, the correct answer is option D. i.e., All of the above.

Note:Synapse also called the neuronal junction, is the location where electric nerve pulses are transferred between two neuronal cells or between the neuron and the gland or muscle cell (effective organ). Neuromuscular junction is a synaptic link between the neuron and the muscle cell.