Purpose: What is the purpose of this exercise? Are there any safety concerns associated with this exercise? If so, list what they are and what precautions should be taken. To understand the structure and function of multipolar neuron,unipolar and bipolar neurons. Also to identify the structures of a nerve. There are no safety concerns for this lab.
Step 1: Relates to Lab Exercise 10/Activity 1, 3, and 4.
Write a brief description of the three slides (Neuron, Spinal Cord Smear and C.S of Myelinated Nerve Fibers) as though you were explaining it to someone who cannot see the slide.
Neuron- There is a reddish rounded shape with lighter thin looking branches these are probably the axon terminals or dendrites. I am thinking this is a multipolor neuron. The reddish rounded figure is the nucleus. There are smaller darker dot, which I am guessing could be the axons. Spinal Cord Smear- A large purple figure with bundles of darker spots, which I believe to be chromatin. The cytoplasm is visible as well as darker purple scattered Nissl bodies. I am not sure I can identify the axon.
C.S of Myelinated Nerve Fibers- There an alternating patterns of blue and pink sheaths running horizontally. There is red nuclei. The lighter area I can identify is the vesicular myelin.
Answer to the questions in Lab Report: Exercise 10: Organization of Nervous Tissue- Activity 1 ,3 AND 4. You can skip answering questions for activities 2 !
Activity 1: Multipolar Neurons
Sketch your observations through the microscope of the neuron, the ox spinal cord smear, and the teased myelinated nerve Please describe what you observed on each slide.
A.What is the function of a neuron? A neuron secretes chemicals to stimulate other cells. Its function is to produce and transmit action potentials
B.What is the difference between a neuron and a nerve? A nerve is a bundle of axons. A neuron is the basic cell of the nervous system and is made of the cell body, dendrites, and an axon.
C.What gives a multipolar neuron its name? The multiple fibers that come off of the cell body.
D.What are the functions of the dendrites and axons? Axons conduct electrical impulses away fro the body and Dendrites conduct electrical impulses toward the cell body.
Activity 3: The Neuroglia and Supporting Cells
Activity 4: Structure of a Nerve
A.Describe the functions of the following parts of a nerve:
Endoneurium: The connective tissue that encloses the myelin sheath of a nerve fiber within fascicullus. Epineurium: This is the most outer layer that surround the peripheral nerve. Perineurium: This is the protective sheath that surrounds bundled fascicles. Fascicle: Bundle of nerve fibers, enclosed by perineurium.
B.What is a nerve? A nerve is bundle of peripheral axons carrying sensory to CNS and motor from CNS.
C. Why are the connective tissue wrappings an important part of nerve structure? Because it connect the spinal cord with peripheral nerves.
D.Differentiate the central nervous system from the peripheral nervous system. The PNS is all the neural structures except the brain and spinal cord. It includes sensory receptors, peripheral nerves, and motor endings. It also provides links to and from the external environment. The PNS can regenerate some and myelination is done by schwann cells. The CNS contains the brain and spinal cord. It incapable of regeneration and myelination in the CNS is accomplished by oligodendrocytes. The major inhibitory neurotransmitter in the CNS is gamma-aminobutyric acid (GABA), while in the PNS it is glycine
Describe the structure of nervous tissue and relate it to its function. There two main cells types in nervous tissue neurons are excitable cells that transmit electrical signals and supporting cells that surround and wrap...