biology4

Experiment 1: Microscopic Anatomy of the Nervous System

The human nervous system is capable of a wide variety of functions. These abilities stem from the microscopic anatomy of this system, which you will observe in this activity.

Materials Spinal Cord Smear Digital Slide Image Myelinated Nerve Fibers Digital Slide Image

Procedure

1. Locate and examine the spinal cord smear and myelinated nerve fiber digital slide images. Then, answer the Post-Lab Questions.

Spinal Cord Smear 100X. Neuroglial cells are closely associated with neurons as they act as supporting cells.

Spinal Cord Smear 1000X.

Myelinated Nerve Fiber 100X.

Myelinated Nerve Fiber 1000X. Schwann cells create a myelin sheath by wrapping around the fiber in a ‘jelly roll' fashion.

Post-Lab Questions

1. Label the arrows in the slide images below based on your observations from the experiment.

2. What is the major function of the neuron?

3. Are the nodes of Ranvier spaced equally along the axon? Why is this significant?

4. Define depolarization.

5. Describe how Schwann cells form the myelin sheath and the neurilemma.

6. What determines whether a neuron is unipolar, bipolar, or multipolar? Draw an example of each below.

Experiment 8: Reflexes (Part II)

In this experiment, you will continue to explore reflexes.

Materials Ruler *Participant

*You must provide

Procedure

1. Hold a ruler approximately 8.0 cm above the outreached hand of your partner. Instruct him/her to catch the ruler between the thumb and forefinger.

2. Record the measurement where your partner caught the ruler in Table 2. Repeat this two more times.

3. Hold the ruler approximately 8.0 cm above the outreached hand of your partner. Tell him/her to close his/ her eyes and try to catch the ruler between the thumb and forefinger after you say the word “release”. Note: Release the ruler immediately after you say the word “release”.

4. Record the measurement where your partner caught the ruler in Table 2. Repeat this two more times.

5. Hold the ruler approximately 8.0 cm above the outreached hand of your partner. Tell him/her to close his/ her eyes and try to catch the ruler between the thumb and forefinger after you pat his/her back. As you release the ruler with one hand, pat your partner's back with the other.

6. Record the measurement where your partner caught the ruler in Table 2.

7. Record the measurement where your partner caught the ruler in Table 2. Repeat this two more times.

Table 2: Reflex Data
Reflex	Trial 1: Distance Caught (cm)	Trial 2: Distance Caught (cm)	Trial 2: Distance Caught (cm)
Visual
Verbal
Tactile