Nervous+system+hw-+kat

1. What are the two major divisions of the nervous system? The two major divisions of the nervous system are the **central nervous system (CNS)** and the **peripheral nervous system (PNS)**.

2. What are the three types of neurons? The three types of neurons are **sensory neurons, interneurons, and motor neurons.**

3. What are the three parts of a neuron? The three parts of a neuron include the cell body, dendrites, and an axon.

4. What is a nerve impulse and how does it spread (this requires a long answer).
 * Nerve impulses** convey information within the nervous system. Measuring nervous impulses uses axons and a voltmeter to measure voltage. The voltmeter allows us to measure the differences between two sides of the axonal membrane. When the axon is not conducting an impulse, the voltmeter records a membrane potential at about **-65 mV** (millivolts), which is called **resting potential**. An **action potential** is when rapid change in polarity cross an axonal membrane as the nerve impulse occurs.

5. Since neurons don't physically touch, how is an impulse transmitted from one neuron to the next? Since neurons don't touch, the can transmit impulses to each other due to neurotransmitters. They are released when they're needed and they combine the receptor proteins on each side of the synapse.

6. What structures compose the central nervous system? The two structures that compose the central nervous system are the **spinal cord** and the **brain**. 7. What are the two main functions of the spinal cord? The two main functions of the spinal cord are to provide a means of communication between the brain and the peripheral nerves.

8. What are the four major parts of the brain and the general function of each? The four major parts of the brain are the **cerebrum**, the **diencephalon**, the **cerebellum**, and the **brain stem**. Cerebrum: controls activities like learning, memory, reasoning, and speech. Diencephalon: regulates homeostasis. Cerebellum: maintains balance in the body Brain Stem: controls visual, auditory, breathing and the body's heartbeat.