Hands On Labs and Discussion Board 4

Nervous tissue consists of 2 main groups of cells, neurons and neuroglia. Neurons conduct electrical impulses while neuroglia provide support. This support can include, but is not limited to: neuronal insulation, immunity, protection, nutrient access, and waste disposal. Neurons, on the other hand, are largely classified by the number of processes per cell. Therefore, both neurons and neuroglia can be classified by their structure and function.

Use the terms provided below to differentiate neurons and neuroglia. Each term will only be used once.

·

· Satellite cells

· Schwann cells

· Ependymal cells

· Oligodendrocytes

· Astrocytes

· Microglia

· Pseudounipolar

· Bipolar

· Multipolar

Activity 3: Organization of Spinal Nerves

Identify the spinal nerves and plexuses (A-K). Each letter will only be used once.

17.

18. Lumbo-sacral plexus

19. Cervical nerves

20. Cauda equina

21. Lumbar nerves

22. Coccygeal nerves

23. Sacral plexus

24. Brachial plexus

25. Thoracic nerves

26. Lumbar plexus

27. Sacral nerves

28. Cervical plexus

Activity 4: Meninges

Several connective tissue membranes called meninges surround the spinal cord and brain. Between these are spaces that contain fluid, fat, or other substances.

Put the structures in order from superficial (1) to deep (8):

29. Subdural space

30. Subarachnoid space

31. Dura mater

32. Pia mater

33. Vertebrae

34. Arachnoid mater

35. Spinal cord

36. Epidural space

Activity 5: Spinal Cord Cross Section

The spinal cord is the major relay center to and from the body and brain. It has sections of both white matter (myelinated axons for sending) and gray matter (cell bodies, dendrites, etc.—basically “thinking matter”). It is connected to the spinal nerves for transmission.

Label the spinal cord (A-J). Each letter will only be used once.

37.

38. Posterior gray horn

39. Dorsal white column

40. Anterior gray horn

41. Lateral gray horn

42. Central canal

43. Ventral white column

44. Lateral white column

45. Posterior root

46. Posterior root ganglion

47. Anterior root

Activity 6: Parts of a Reflex Arc

Complete the chart below by adding in the parts and functions of a typical reflex arc

Activity 6: Reaction Time

Introduction

Reaction time is a measure how quickly organism responds to a stimulus. Reflexes and reactions, while seeming similar, are quite different. Reflexes are involuntary, used to protect the body, and are faster than a reaction. Reflexes are usually a negative feedback loop and act to help return the body to its normal functioning stability, or homeostasis. Reactions are actually a symphony of hundreds of thousands of neurons working together to produce a conscious decision. We have to decide what we would like to do regarding this stimulus. Furthermore, the quickness of reaction times can differ depending on what type of stimulus you are reacting to and what kind of task you are doing.

Test 1- Visual Response

Procedures:

1. You will need one 12-inch ruler (that can read cm) to complete this test.

2. Have your subject sit at a table with their dominant hand over the edge.

3. Hold the ruler at the 30 cm mark so that the 0 cm end is just at your subject’s index finger.

4. Tell your subject that when you release the ruler, they are to grab it as fast as possible.

a. DO NOT MAKE ANY SOUNDS OR GESTURES THAT INDICATE WHEN YOU WILL DROP IT!

b. They will need to only react to the visual stimulus of seeing the ruler being released.

5. Record the cm mark above the index finger in the chart below.

6. Repeat the experiment 3 more times.

7. Switch with your subject and you do the visual only catch 4 times as well.

Test 2- Auditory Response

Procedures:

1. Have your subject sit back at a table as they did during the first test. We will still be using the dominant hand

2. Blindfold your subject.

3. Tell the subject that you will say “RELEASE” as you release the ruler.

4. Once they grab it, record the centimeter mark and repeat 3 times.

5. Switch with your subject and complete 4 times

Test 3- Tactile Responses

1. Have your subject sit back at the table with their dominant hand once again over the edge.

2. Blind fold subject again.

3. Tell the subject that you will touch the shoulder of their non-dominant arm as you release the ruler.

a. Give NO AUDITORY CUES- SIMPLY TOUCH

4. Record the centimeter mark and repeat 3 times

5. Switch with your subject and complete 4 times.

58. Complete the table with UNITS (cm and sec as needed)

Conclusion Questions

Insert 2 pictures of you and your subject completing the activity.

59.

60.