Nervous System

1. Which of the following structures is the primary control center of the nervous system?

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2. What is the primary function of the myelin sheath around a neuron’s axon?

• To protect the neuron from physical damage.
• To insulate the axon and increase the speed of electrical impulses.
• To provide nutrients to the neuron.
• To transmit signals between neurons.

4. What is the primary function of the blood-brain barrier?

• To enhance the flow of blood to the brain.
• To protect the brain from harmful substances and maintain homeostasis.
• To allow all substances to freely enter the brain.
• To regulate the temperature of the brain.

5. Which neurotransmitter is most closely associated with the regulation of mood and emotional responses?

• Dopamine
• Norepinephrine
• Serotonin
• Acetylcholine

The ________________ is a part of the brainstem that controls essential functions such as heart rate, breathing, and blood pressure.

Neurons communicate with each other across synapses using ________________, which are chemical messengers released from the axon terminals of one neuron to affect another neuron or muscle.