1 - GRQ- Cells of the nervous system PDF

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Guided reading questions Cells of the nervous system Read pages 381-389. Do not hesitate to use the web when a question is not specifically addressed in the textbook.

Structure of a neuron 1. Define the following terms Soma- cell body of a neuron Nissl bodies- cluster of free ribosomes and rough ER that are dark under a microscope Dendrites- carry electrical signals to the cell body Axon- long “arm” that carries signal away from the cell body Axon hillock- first part of the axon where an action potential is generated Axolemma – plama membrane of the axon Axon terminal/synaptic knob – end of the axon w/ synaptic vesicles w/ neurotransmitters

2. Nissl bodies are responsible for the gray color of the gray matter, regions in the CNS that are highly enriched in cell bodies. Can you hypothesize why Nissl bodies exist in neurons and not in other cells? Nissl bodies function to make and release proteins for the neuron. They are found in the cell body and dendrites, not in the axon. Neurons constantly send electrical signals and need proteins that the Nissl bodies make. They also try and repair damages to the neuron. 3. True/False There are multiple dendrites in all neurons 4. True/False Most neurons have a single axon

No need to memorize the four different types of neuron structure depicted in table 11.1

Neuroglia- Types of neuroglia 5. What distinguishes a neuron from a neuroglia cell? Hint: you might need to explore beyond your book A neuron is a nerve cell that transmit electrical and chemical information around the body. It has an axon and dendrites extending from the soma. A neuroglia cell is a tissue that deal with connectivity in the nervous system. Does not have axon or dendrites and support the neurons by making myelin sheath, anchoring neurons, become phagocytes, and release fluid.

6. Describe each of the 6 types of neuroglia. In each type, focus on the functions rather than the structures, and limit yourself to 2 sentences per each type CNS Astrocyte: anchors neurons and blood vessles, help form the BBB, repair damaged tissue, and regulate the extracellular environment. Oligodendrocytes: form myelin and myelin sheaths on the axon in CNS Microglia: act as phagocytes and cause inflammation Ependymal: line cavities, cilia circulate spinal and brain fluid and some secrete it PNS Schwann: form myelin sheaths on axons in PNS Satellite: surround and support cell body and regulate extracellular environment...