which of the following is a correct pathway of a nerve impulse?
A. Synapse - cell body - dendrites - axon
B. Axon - cell body - synapse - dendrite
C. Dendrite - cell body - synapse - dendrite
D. Dendrite - cell body - axon - synapse
To determine the correct pathway of a nerve impulse, we need to understand the structure and function of neurons. Neurons are the specialized cells in our nervous system that transmit electrical signals, also known as nerve impulses.
A. Synapse - cell body - dendrites - axon: This pathway is incorrect. The synapse is the junction between two neurons, where the electrical signal is transferred from one neuron to the next. The axon is a long fiber-like extension of a neuron that carries the nerve impulse away from the cell body, while dendrites receive incoming signals from other neurons.
B. Axon - cell body - synapse - dendrite: This pathway is incorrect. The axon carries the nerve impulse away from the cell body, and the dendrites receive incoming signals. The synapse is where the signal is transferred from one neuron to the next, so it typically occurs between an axon and a dendrite.
C. Dendrite - cell body - synapse - dendrite: This pathway is incorrect. The dendrites receive incoming signals, and the cell body processes and integrates these signals. The synapse is where the signal is transferred from one neuron to the next.
D. Dendrite - cell body - axon - synapse: This pathway is correct. The dendrites receive incoming signals, which are then transmitted to the cell body. The cell body integrates and processes these signals, and if the threshold is reached, it generates an electrical impulse that travels along the axon. The axon carries the nerve impulse away from the cell body, and at the end of the axon, the signal is transmitted to the next neuron through a synapse.
Therefore, the correct pathway of a nerve impulse is D. Dendrite - cell body - axon - synapse.