What does the neuron doctrine assert about the organization of the nervous system?

What does the neuron doctrine assert about the organization of the nervous system?

• A. The brain functions as a single, undifferentiated unit.
• B. Neurons transmit signals exclusively via chemical synapses.
• C. The nervous system is composed of individual, discrete cells called neurons.
• D. Neurites do not communicate with each other.

Answer: (C)

The main idea being tested is that the nervous system is built from individual, separate cells called neurons. The neuron doctrine holds that neurons are distinct units with their own cell bodies and processes, and they communicate with each other across specialized gaps called synapses. This view rejects the notion of a single, continuous network and instead emphasizes discrete cellular units that connect to form circuits. This makes the correct choice the best because it captures the fundamental claim: the nervous system is organized as individual neurons, not as a single undifferentiated mass. The other statements conflict with this idea. While neurons do communicate at synapses, communication is not limited to chemical synapses only—electrical synapses can also occur—so saying signals are transmitted exclusively chemically is incorrect. And neurites (axons and dendrites) do communicate with each other via synapses, so saying they do not communicate is inaccurate.

The main idea being tested is that the nervous system is built from individual, separate cells called neurons. The neuron doctrine holds that neurons are distinct units with their own cell bodies and processes, and they communicate with each other across specialized gaps called synapses. This view rejects the notion of a single, continuous network and instead emphasizes discrete cellular units that connect to form circuits.

This makes the correct choice the best because it captures the fundamental claim: the nervous system is organized as individual neurons, not as a single undifferentiated mass. The other statements conflict with this idea. While neurons do communicate at synapses, communication is not limited to chemical synapses only—electrical synapses can also occur—so saying signals are transmitted exclusively chemically is incorrect. And neurites (axons and dendrites) do communicate with each other via synapses, so saying they do not communicate is inaccurate.