Cells of the Nervous System
\ In what ways are neurons similar to other cells in the body? In what ways are they different?
Similar: They have organelles (such as mitochondria and nucleus)
Difference: The way they communicate with other neurons over long distances and morphology (their shape) \n What were the contributions of Camillo Golgi and Santiago Ramon y Cajal to our understanding of neurons?
Golgi: created the Golgi Stain that is a way to see neurons over a light microscope
Santiago and Cajal: Used the Golgi Stain and theorized that the barin was made up of individual units/cells. This was proven to be correct after the electron microscope was invented and now these cells are called neurons.
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Know the parts of a neuron and their functions. Be able to label the parts of a neuron.
Axon, dendrites, neuron, axon hillock, myelin, axon terminal, synaptic cleft, neurotransmitters, presynaptic cell, post synaptic cell, vesicles
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Draw and label a synapse, including the following: presynaptic cell (terminal), postsynaptic cell (dendrite or dendritic spine), synaptic cleft.
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Compare and contrast multipolar, bipolar, and unipolar neurons. Of these three types, what is a somatosensory neuron and what is a motor neuron?
Multipolar Neurons: have many dendrites and one axon (MOTOR NEURON)
Bipolar Neurons: have one axon and one dendrite (SOMATASENSORY NEURON)
Unipolar Neurons: has a cell body that extends in a branch and it becomes axons going in two different directions (SOMATASENSORY NEURON)
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Describe the structure of the cell membrane.
It is a double layer of fatty molecules also knows as the PHOSPHLIPID BILAYER; this has specialized channels that allow ions of a specific type to pass through.
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Know the terms: CNS, PNS, nucleus (not the organelle), ganglion, nerve, tract, white matter, gray matter
Central Nervous System: portion of the nervous system that includes the brain and the spinal cord
Peripheral Nervous System: the portion of the nervous system that includes all the nerves and neurons outside the brain and spinal cord
Nucleus: a collection of neuronal cell bodies within the central nervous system
Ganglion: a structure containing a number of nerve cell bodies, typically linked by synapses, and often forming a swelling on a nerve fiber.
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Nerve: collection of axons bundled together outside the central nervous system
White matter: light colored layer of tissue, consisting mostly of myelin-sheathed axons mostly transmits information
Gray matter: areas of the brain that are dominated by cell bodies and are devoid of myelin, mostly receives and processes information
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Know the different types of glial cells and their functions.
Oligodendrocytes and Schwann Cells have the same function of MYELINATION but happen in different places. Oligodendrocytes are located in the Central Nervous System and Schwann Cells are located in the Peripheral Nervous System.
Microglia: are glial cells that search and respond to injury and disease (the immune cells of the brain)
Astrocytes: a star shaped glial cell that does a lot of things like: stretching between neurons and fine blood cells, controlling local blood flow to increase the amount of blood reaching more-active brain regions, and forming the tough outer membranes that swaddle the brain, and secrete chemical signals that affect synaptic transmission .
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What/where is the blood brain barrier? What does it keep out, let in? What are the implications of this for drug use and medicine?
It is the endothelium that is a thin layer of cells that lines the interior surface of blood vessels. The endothelial cells form walls of capillaries that don’t let infections though, but this can be an issue when wanting to deliver pharmaceuticals into the brain. Keeps out most viruses, bacteria, and chemicals.
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For the staining techniques, know what each one looks like and specifically what it allows you to visualize.
Golgi Stain: allows for visualization of individual neurons
Nissl Stain: Selectively stains bell bodies
Weigert: Electron Microscopy (very high magnification; provides information about the detail of neuronal structure)