<img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" />
You are reading an older version of this FlexBook® textbook: Human Biology Nervous System Teacher's Guide Go to the latest version.

# 4.3: Activities and Answer Keys

Difficulty Level: At Grade Created by: CK-12

## Activity 3-1: Picture a Nerve Cell

### PLAN

Summary Students design drawings of neurons, which they join in chains or networks. The model nerve network helps them visualize and learn that information flows in one direction from dendrites to the cell body, along the axon to dendrites on the next neuron, and through synapses.

Objectives

Students:

\begin{align*}\checkmark\end{align*} identify the parts of the neuron: axon, dendrites, and cell body.

\begin{align*}\checkmark\end{align*} explain the relationship between the structure and function of a neuron.

\begin{align*}\checkmark\end{align*} explain the function of neurotransmitters.

\begin{align*}\checkmark\end{align*} demonstrate how neurons transmit messages from one place to another in the human body.

Student Materials

• Activity Report
• Markers, Crayons, Colored pencils, Construction paper

Teacher Materials

• Sample pictures of neurons
• Microscope slide of neuron
• Resource 1 from Activity 3-2: Drug Effects on Neurons.

Prior to this activity, encourage students to draw a neuron and explain their design. Gather art materials or ask students to bring them.

Estimated Time Approximately one or two 50-minute class periods, depending on what work is assigned as homework

Interdisciplinary

Visual and Performing Arts Students can create and/or embellish their neuron diagrams in art classes.

Home Education/Art Use fabric decorating paint to paint neuron designs on T-shirts.

Prepare a display area for completed neuron pictures. Discuss the structure of neurons with students.

Use the “holes” from punched paper to represent the neurotransmitter at the synapse, as it carries the chemical message from neuron A to neuron B.

Use some student drawings when learning about the reflex arc.

### IMPLEMENT

Introduce Activity 3-1 by referring students to Figure 3.1 in the student text as a guide.

Steps 1-3 This activity can be done individually, in pairs, or with small groups. Make sure students have their texts for reference.

Step 4 Make sure students keep a space between their neurons to represent a synapse. Refer students to Figure 3.3. Discuss the structure of neurons with students.

Extensions

Use computer graphics to create a two-dimensional model of a neuron. Invite students to research neurotransmitters and health, with respect to depression and suicide. Possible resources include community hospitals, health clinics, and hotlines, as well as libraries, local medical experts, and computer information searches, e.g., Web sites for the National Institutes of Health (NIH) and the Society for Neurobiology.

### ASSESS

Use the model of a neuron and the written responses on the Activity Report to assess if students can

\begin{align*}\checkmark\end{align*} identify the location of the specific parts of a neuron (axon, dendrites, and cell body).

\begin{align*}\checkmark\end{align*} explain how each part of a neuron functions, using diagrams.

\begin{align*}\checkmark\end{align*} demonstrate what a neurotransmitter is and how it works.

\begin{align*}\checkmark\end{align*} describe how a message is transferred through a synapse between two neurons.

\begin{align*}\checkmark\end{align*} show how the transfer of a message along a chain of neurons allows the nervous system to function properly.

## Activity 3-1: Picture a Nerve Cell – Activity Report Answer Key

• Sample answers to these questions will be provided upon request. Please send an email to teachers-requests@ck12.org to request sample answers.
1. Describe the path a nerve impulse takes. Include the pathway taken within a neuron and the way an impulse travels between neurons. Add a sketch, with labels and arrows, to indicate the direction of the impulse or message.
2. What is the role of the neurotransmitter?
3. What effects would certain drugs have on the function of a neuron? (You may want to read the information on Resource 1 of Activity 3-2: Drug Effects on Neurons to answer this question.)
4. What questions do you have about how nerve cells work to carry messages throughout your body?

A suggested response will be provided upon request. Please send an email to teachers-requests@ck12.org.

• Some poisonous snakes have venom that can paralyze a person. How do you think the venom affects the nervous system?
• What kinds of symptoms do you think a person would have if the axons of his or her nerve cells were damaged?

## Activity 3-2: Drug Effects on Neurons

### PLAN

Summary Students demonstrate the normal transmission of dopamine across a synapse in the brain and then the effects of the drug cocaine on neurons. These activities help students visualize and learn how drugs disturb the normal function of nerve cells and, in this case, the neurotransmitter dopamine.

Objectives

Students:

\begin{align*}\checkmark\end{align*} demonstrate and explain the transmission of the neurotransmitter dopamine across a synapse.

\begin{align*}\checkmark\end{align*} demonstrate the effects of cocaine on the normal function of neurons.

\begin{align*}\checkmark\end{align*} explain the effects of cocaine on neurons.

Student Materials

• Resources 1, 2, 3
• Activity Report

Message Sender

Dopamine Pump

Cocaine

• Tennis balls (about 20 to 30)
• 2 chairs
• Scissors
• Yarn or string

Teacher Materials

• Resources 1, 4, 5, and 6
• Transparencies of Resources 2 and 3
• Charts and other visuals showing the synapse between two neurons

Prior to the activity, have students read Resource 1 and discuss the content in class.

Gather materials and ask students to bring in tennis balls.

Interdisciplinary

Physical Education Students discuss drug testing for bus and train drivers, pilots, physicians, and participants in competitive sports.

Prerequisites

Students should review the structure and function of neurons, synapses, and how neurotransmitters work.

You may want students to review or learn about the effects of stimulant and depressant drugs.

### IMPLEMENT

Introduce Activity 3-2 by discussing the structure and function of neurons, synapses, and how neurotransmitters work. Review the effects of stimulant and depressant drugs.

Step 1 Have students read Resource 1. You may want to make a transparency of Resource 1 and discuss the resource as students read along.

Step 2 Explain the process shown in Resource 2 titled Normal Transmission of Dopamine to students. Ask students to explain how dopamine is transferred from one neuron to another neuron across the synapse in order to determine how much they know about the process.

Step 3 Explain the process shown in Resource 3 titled Cocaine's Effect on Neurons to students.

Steps 4-5 Assign specific classification of drugs (stimulant or depressant) to groups of students. Use Resource 6 to record observations of the presentation.

Extend Activity 3-2 by having students research the use of drugs in medicine and the possible long-term effects of illicit drugs on the body.

### ASSESS

Use observations of student's performance and written responses on the Activity Report to assess if students can

\begin{align*}\checkmark\end{align*} demonstrate and explain the transmission of the neurotransmitter dopamine across a synapse in the brain.

\begin{align*}\checkmark\end{align*} demonstrate and explain the effects of cocaine on the normal transmission of dopamine across the synapse.

\begin{align*}\checkmark\end{align*} explain the effects of stimulants and depressants on a neuron.

\begin{align*}\checkmark\end{align*} create a presentation on the effects of stimulants and depressants on the nervous system.

## Activity 3-2: Drug Effects on Neurons – Activity Report Answer Key

• Sample answers to these questions will be provided upon request. Please send an email to teachers-requests@ck12.org to request sample answers.
1. Discuss the role of dopamine in the transmission of a nerve impulse.
2. Describe the effects of cocaine on neurons.
3. Distinguish between a stimulant and a depressant.
4. How do stimulants and depressants affect nerve cell function?
5. What was the most interesting thing you learned from this activity?

• Sample answers to these questions will be provided upon request. Please send an email to teachers-requests@ck12.org to request sample answers.
1. Name and describe the three basic parts of a neuron.
2. What is a synapse?
3. Why are neurotransmitters important?
4. Why are nerve impulses like a “human wave in a sports stadium”?

## Activity 3-1: Report Picture a Nerve Cell (Student Reproducible)

1. Describe the path a nerve impulse takes. Include the pathway taken within a neuron and the way an impulse travels between neurons. Add a sketch, with labels and arrows, to indicate the direction of the impulse or message.

2. What is the role of the neurotransmitter? (Hint: see Procedure Step 3)

3. What effects would certain drugs have on the function of a neuron? (You may want to read the information on Resource 1 of Activity 3-2: Drug Effects on Neurons to answer this question.)

4. What questions do you have about how nerve cells work to carry messages throughout your body?

## Activity 3-2 Resource 1: Drug Effects on Neurons (Student Reproducible)

Science News Report

Drugs affect the body by influencing the regulation of cellular processes. In many cases, the cellular processes that are most disrupted by drugs are those carried out by neurons. Drugs affect nerve cells by interfering with their ability to receive and transmit signals. The synaptic phase of nerve signal transmission depends on the release of neurotransmitter molecules, the diffusion of these molecules across the synaptic space, and the way a given neurotransmitter is able to structurally “fit into” and later “drop out of” a receptor. Some drugs might affect nerve signal transmission by increasing or decreasing the amount of neurotransmitters in the synaptic space. Other drugs might even “take the place” of neurotransmitters on the receptors located on a synaptic membrane. These drug actions occur at synapses and can make nerve signals more intense, less intense, or completely prevent the signal's transmission. The influence of these drugs on thought, mood, and behavior results from the drugs' effects on nerve cells.

Drugs that affect the nervous system include stimulants and depressants.

Stimulants

The stimulants are a group of drugs that speed up cellular processes causing an increase in heart rate, blood pressure, body temperature, and rate of breathing. Stimulants increase signal transmission at synapses that in turn stimulate nervous system activity. Normally, your nervous system does a good job of correctly balancing excitation and inhibition. However, the balance is disrupted by stimulants in a way that leads to anxiety, restlessness, dizziness, headaches, inability to sleep, and tremors. Examples of stimulants include caffeine, nicotine, and amphetamines.

Depressants

The depressants are a group of drugs that slow down or decrease the actions of the nervous system. They enhance the activity of inhibitory nerve signal pathways in the brain. There are two types of depressants-sedatives and analgesics. Sedatives are drugs that have a generalized effect on the function of the nervous system and produce relaxation. Analgesics, such as aspirin, have a “painkilling” effect on nerve pathways. Some of the depressants, such as opioids and alcohol, have both sedative and analgesic effects. Depressants lower blood pressure and body temperature and decrease muscle action and heart rate. All depressants are addictive. Examples include barbiturates and alcohol.

Dopamine

Numerous substances are known neurotransmitters in the brain. Many of these are amino acids or derivatives of amino acids. They serve as chemical messengers between nerve cells. Neurons containing the neurotransmitter dopamine are clustered in the midbrain.

Cocaine

Cocaine comes from the cocoa plant found in South America. It is used in medicine as an anesthetic for eye, ear, nose, and throat surgery. Cocaine obtained illegally is known on the streets as “Coke” “C” “snow,” “blow,” “toot,” “rock,” or “crack.” It can be smoked, snorted, or injected. “Freebasing” is the smoking of cocaine that has been converted to a pure base. Crack, which is extremely addictive, is a rocklike mixture of cocaine and baking soda that is smoked.

Cocaine is a powerful central nervous system stimulant. While cocaine's effects are very similar to amphetamines', they usually are more intense and tend to magnify feelings of self-confidence and mental alertness. Cocaine can cause a powerful heightened state of pleasure. This euphoria or feeling of being high lasts only a short time depending on how the cocaine is taken. When the drug's effect wears off, the person is left feeling let down and depressed. The “let down” is so powerful that it leads to a strong desire to take the next dose of cocaine to feel good again. Cocaine is an extremely addictive drug.

Cocaine, like amphetamines, affects the synaptic terminals of neurons that release dopamine. Cocaine increases the amount of dopamine released from neurons. However, unlike amphetamines, cocaine also interferes with the body's normal mechanism for removing dopamine molecules.

Cocaine is among the most dangerous of illegal drugs. A single use of cocaine can cause the heartbeat to become irregular and the coronary arteries (which nourish the heart muscle cells) to constrict. In extreme cases cocaine use can lead to a heart attack and sudden death. Repeated snorting of cocaine can do serious damage to the nasal passages. Abusers may feel paranoid, suffer shaking and convulsions, and have unpredictable behavior.

Pregnant mothers who use cocaine endanger their babies' health. Cocaine constricts the blood vessels carrying nutrients to a developing baby in the womb. At birth, the infant can be addicted to cocaine just like the mother.

## Activity 3-2 Resource 4: Drug Effects on Neurons (Student Reproducible)

Part 1

Demonstrate for your class the normal transmission of dopamine. Three students volunteer for the demonstration.

Setup-

• Dopamine is represented by tennis balls.
• “Message sender” sits on a chair on the left.
• “Message receiver” sits on a chair about 3 feet to the right.
• “Dopamine pump” stands near the “neuron message sender.”

Using an overhead transparency of the diagram, discuss the process for the normal transmission of dopamine. A possible narrative for this discussion:

1. The neuron message sender releases dopamine in little packets. The “neuron message sender” shows the class a tennis ball.
2. The neuron message sender releases dopamine into the synapse. The neuron message receiver absorbs the dopamine at the receptor site. The “neuron message sender” tosses one tennis ball at a time to the “neuron message receiver.”
3. As dopamine accumulates in the synapse, the dopamine pump recycles or takes the dopamine back into the neuron message sender. When the “neuron message receiver's” hands are full, the “neuron message receiver” tosses the ball up in the air, and it is caught by the “dopamine pump” and given back to the “neuron message sender.”
4. Repeat this demonstration using a different group of students. Students explain this process to each other and then volunteer to present their explanations to the class.

## Activity 3-2 Resource 5: Drug Effects on Neurons (Student Reproducible)

Part 2

Demonstrate for your class cocaine's effect on neurons. At least four student volunteers will help with the demonstration.

Setup-

• Dopamine is represented by tennis balls.
• “Message sender” sits on a chair on the left.
• “Message receiver” sits on a chair about 3 feet to the right.
• “Dopamine pump” sits on the floor next to the “neuron message sender.”
• “Cocaine” is waiting in the wings.
1. The neuron message sender releases dopamine in little packets. The “neuron message sender” shows the class a tennis ball.
2. The neuron message sender releases dopamine into the synapse. The neuron message receiver absorbs the dopamine at the receptor site. The “neuron message sender” tosses one tennis ball at a time to the “neuron message receiver.”
3. As dopamine accumulates in the synapse, the dopamine pump recycles or takes the dopamine back into the neuron message sender. When the “neuron message receiver's” hands are full, the “neuron message receiver” tosses the ball up in the air, and it is caught by the “dopamine pump” and given back to the “neuron message sender.”
4. When cocaine is introduced into the body, it blocks the dopamine pump and prevents the recycling of dopamine into the message sender. The “cocaine” holds the hands of the “dopamine pump” so that they cannot catch the extra balls or hand them to the “neuron message sender.”
5. When the extra dopamine cannot be pumped back to the neuron message sender, an excess of dopamine is absorbed by the receptor sites on the neuron message receiver. The result of this excess is that you feel really high. “Neuron Message Receiver” throws all the tennis balls up in the air. The balls are not caught by the “Dopamine Pump.” They stay with the “Neuron Message Receiver.” The accumulating balls and chaos represent the “high.”
6. Repeat this demonstration using a different group of students. Students explain this process to each other and then volunteer to present their explanations to the class.

## Activity 3-2 Resource 6: Drug Effects on Neurons (Student Reproducible)

_____________________________ _____________________________

_____________________________ _____________________________

_____________________________ _____________________________

_____________________________ _____________________________

Presentation Guidelines: Drug Classification ____________________________

1. Content #\begin{align*}\#\end{align*}Points ______________

drug classification: stimulant or depressant effects of drug on neuron effects of drug on dopamine transmission

2. Accuracy/Completeness of Content #\begin{align*}\#\end{align*}Points ______________

neat, clear, accurate serve to guide viewer toward improved knowledge of drug effects aesthetically pleasing

3. Presentation #\begin{align*}\#\end{align*}Points ______________

good eye contact and voice projection all group members contribute equally clear, organized presentation engaging, interesting

4. Creativity/originality #\begin{align*}\#\end{align*}Points ______________

presentation reflects thoughtful design effective and appropriate use of visual tools such as diagrams, pictures, and graphs

## Activity 3-2 Report: Drug Effects on Neurons (Student Reproducible)

1. Discuss the role of dopamine in the transmission of a nerve impulse.

2. Describe the effects of cocaine on neurons.

3. Distinguish between a stimulant and a depressant.

4. How do stimulants and depressants affect nerve cell function?

5. What was the most interesting thing you learned from this activity?

6 , 7 , 8

## Date Created:

Feb 23, 2012

Apr 29, 2014
Save or share your relevant files like activites, homework and worksheet.
To add resources, you must be the owner of the section. Click Customize to make your own copy.