Warm Up Objective: Scientists will describe the neuron by creating and analyzing a model. 1. What is the topic? 2. What will you be doing? 3. Why is this important? 4. How will you know if you have done well?

Warm Up Objective: Scientists will describe the neuron by creating and analyzing a model. 1. What is the topic? The neuron 2. What will you be doing? Creating and analyzing a model 3. Why is this important? Understand more about the body, future career 4. How will you know if you have done well? Able to describe the neuron, completed work

The Neuron—Background Information

The Neuron--Diagram

The Neuron--Model Using the materials provided (chalk markers, construction paper, other art supplies), create a model of a neuron Label the components of a neuron Describe how the neuron functions

Analysis—Answer on lined paper and staple to your paper 1. What is the purpose of the dendrites? 2. What is the purpose of the axon hillock? 3. How do the Schwann cells help make the nerve impulse go faster? 4. What role does calcium play in the movement of the nerve impulse? 5. You may have heard the saying, “Form follows function.” How does the nerve cell reflect this saying? 6. What is different about chemical transmission and electrical transmission of a nerve impulse? 7. What would a disease of the myelin sheath (Schwann cells) do to the transmission of nerve impulses? 8. If neurotransmitters bind to the receptors on the next neuron (post-synaptic neuron), what do you think would happen if a particular drug mimics the neurotransmitter and fits into the receptor, blocking the neurotransmitter from doing its job? 9. What two locations on a neuron membrane can we find synapses? 10. Describe the different neurons. Why do we have different types of neurons?

Analysis--Discussion Dendrites receive information from other neurons. Can be a part of the synapse as the post-synaptic neuron. The axon hillock is a space in the cell body that accumulates all of the action potentials. Sums them up to determine if the nerve impulse will continue down the axon. Schwann cells are composed of a material called myelin, which acts as an insulator allowing the nerve impulse to jump across them to the next cell, thereby increasing its speed. Calcium enters the axon terminal and as it does, it causes the vesicles to move to the membrane and dump their neurotransmitters into the cleft. Without the calcium, the impulse would stop at the axon terminal.

Analysis--Discussion The neuron has a shape that allows it do its jobs. The dendrites are branch-like and so can communicate with many other neurons. The long axon covered in myelin allows the impulse to quickly travel from neuron to neuron. The axon terminals allow the neuron to communicate with more than one other neuron. Chemical transmission is done by the transmitters which are chemicals across the synapse since the electrical impulse cannot jump across that space. Electrical transmission is like electricity in that the nerve impulse happens down the axon due to the movement of ions which have an electrical charge.

Analysis—The Discussion Diseases like multiple sclerosis will have a damaged myelin sheath which then greatly diminishes the speed of the impulses. All actions are slower. Certain street drugs affect the synapse in different ways. Some have a similar shape to the neurotransmitters and will block it. This will stop the transmission of the impulse and can cause depression or the opposite of stimulation. The synapse can be on the dendrite’s membrane or on the cell body membrane. Motor neurons are responsible for transmitting signals to activate muscles and glands. Sensory neurons send signals from outside the body into the central nervous system. Interneurons act as connectors between neurons