Human Anatomy and Physiology Web Quest

Nervous System

Task

We will be investigating the nervous system in this activity. 1st you will learn more about the anatomy and physiology of nerve impulses so that you understand how the electrochemical impules are conducted. Then, you will investigate the central nervous system and specifically how the brain is structured and how it functions. You will also take a quick look at how traumatic brain injury can occur and how certain substances affect brain chemistry through the use of PET scans. Finally, you will investigate the mechanism of how spongiform encephalitis, Mad Cow's disease, occurs in humans.

1. Conduction of Nerve Impluses

View the animations of saltatory conduction and continuous conduction by finding the "propagation of the action potential." Describe the similarities and differences in these two methods of neural impulse transmission.

---

2. Pre-Synaptic and post-synaptic transmission

Go through the animation of a nerve impulse from the pre-synaptic neuron to the post-synaptic neuron and answer the following questions.

a. What is the space in between the two neurons?

b. When the action potential reaches the terminal end of the pre-synaptic neuron how does it continue?

c. What does a neurotransmitter bind to when it crosses the synapse to the post-synaptic neuron?

d. What stores neurotransmitters?

---

3. Anatomy of the Brain

Click on the link to the pbs tour of the brain web site. Explore the brain by area and answer the following questions.

a. Where is the cerebellum located? What does it control?

b. Where does the parietal lobe receive its impules? What information does it process?

c. How does the temporal lobe differ for right handers and left handers?

d. Where do the frontal lobes lie and what do they control?

e. Where is the occipital lobe located? What sense is accociate with this part of the brain?

f. Why is the brain stem referred to as a primitive area of the brain?

g. What does the corpus callosum connect? What does it do for the right and left brain parts of the brain?

h. What does the limbic system regulate? What are two parts of the limbic system?

---

4. Functions of the Brain

Explore the brain by function and answer the following questions.

a. Vision. In terms of vision, nerve impulses travel along the retina through the _________ to the brains visual processing centers in the ________ lobe. What area contains more neurons than the rest of the brain put together?

b. Hearing. The _______ nerve conducts impulses from the Organ of Corti in the ear to the ________ cortex in the ________ lobe.

c. Smell. What travels through the air that we actually smell? What is different about olfactory senses as opposed to other senses? The impulses travel directly to the _______ centers of the cerebral _______. Signals travel along the ________ nerve to the _______ bulb of the _______ system.

d. Touch. Certain neurons fire an impulse when they encounter pressure, _______, ______, _______, and ______. Describe how the impulses travel next.

e. Taste. What structures integrate taste into memories and where are these structures found?

f. Short-term memory. What areas are responsible for short-term memories?

g. Long-term memory. Where is long-term memory of abstract ideas stored in the brain? Where is long-term memory of activities such as riding a bike located?

h. Speech. Damage to what area in the left frontal lobe could cause a person to have difficulty producing speech sounds? Damage to what area could cause you to not be able to describe to your friend what The Grapes of Wrath was about?

i. Emotion. What area controls emotions? What are some type of emotions? Improper wiring between the limbic system and what other area could cause someone to react very quickly and have anger issues or poor emotional control?

j. Movement. What area coordinates balance movement and posture? What type of memories are stored in the cerebellum?

---

5. Brain Probe

Let's probe the brain. What area did you map out?

---

6. PET Scans, Brain Chemistry, and Drugs

There are certain technologies such as PET scans and MRI scans which allow us to see brain activity.

a. Run a PET scan for dopamine. How is the brain chemistry of a person addicted to alcohol different from someone who is not? What is dopamine?

b. Run a PET scan for glucose. How is the brain chemistry of a person who is addicted to methamphetamine different than someone who is not?

c. Run a PET scan for MAO enzyme. How is the brain chemistry of a person who smokes tobacco different than someone who does not when they smoke?

---

7. Diseases of the Brain-Spongiform Encephalitis

Mad Cows disease! Each question corresponds to a different page in this animation in order.

a. Where does the term prion come from? 1st page

b. Where does the prion enter the cell? 2nd page

c. A self-replicating protein! How does the prion replicate? 3rd page

d. What causes hereditary forms of prion diseases? 4th page

e. Why is Mad Cow's disease called spongiform encephalitis? 5th page

f. What is formed as a result of neuronal cell death? 6th page

g. How many types of prion diseases are shown? 7th page

h. How did Kuru spread in the Fore people of New Guinea? 8th page

This concludes Mondays activity. The following are for another day.

---

8. Neurotransmitters and Synaptic Transmission

1. Move the molecules around in the program that shows the types of neurotransmitters. What are the four neurotransmitters that you see here?

---

9. The Twelve Cranial Nerves

1. Click on each cranial nerve beginning with the Olfactory Nerve (I). What do these nerves carry impulses for? Use the main menu button to go back.

2. Optic Nerve (II). What do the impulses for this nerve control?

3. Oculomotor (III). What types of nerves does this cranial nerve mainly consist of? What are some functions of the oculomotor nerve?

4. Trochlear (IV). Are these smallest or largest of the cranial nerves? What do they control?

5. Trigeminal (V). What are the trigeminal nerves responsible for?

6. Abducens (VI). Where do the abducens originate and what do they control?

7. Facial (VII). What types of motor impulses do these nerves carry? What type of sensory impulses does this nerve carry?

8. Vestibulocochlear (VIII). Where does this nerve originate from? What are its two branches and what are they responsible for?

9. Glossopharyngeal (IX). What areas of the superior part of the body are these nerves associated with?

10. Vagus (X). What is unique about the vagus nerves? From where do these nerves carry sensory and motor impulses?

11. Accessory nerves (XI). What muscles do these nerves serve?

12. Hypoglossal (XII). What do these nerves pass into? What functions do they serve?

13. Click next and fill in the blanks with the corresponding cranial nerves. Write the order of your responses on paper.

---

10. Depression and Prozac

1. Click on the "How Prozac Can Help" article. What neurotransmitter is associated with depression? How does Prozac increase the levels of this transmitter. It is an SSRI, selective serotonin reuptake inhibitor.

2. What is different between the normal and depressed neuron with synapse? How does the animation portray the effects of prozac in the prozac neuron animation?

---