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Nervous System
SPC Goswami ATE1211
Question | Answer |
---|---|
What shape is a nervous cell? | Smooth or Stellate |
What is another name for Cell Body? | Soma |
What is a Chromatophilic Substance comprised of? | clusters of Ribosomes |
Microtubules extending from the Axon are known as? | Neurofibrils |
Where Soma are concentrated they form? | Ganglia or Nuclei |
What are Dendrites? | Short, highly Branched extensions of the cell body |
What do Dendrites do? | carry Impulses INTO/TOWARD the cell body |
What is an Axon? | Long, Slender extension of the cell body |
What is the function of the Axon? | to carry impulses AWAY from the cell body |
What are Axons insulated by? | Neuroglia |
Why are Axons insulated? | to protect them and other neurons from the electrical impulses traveling within them |
Name 2 types of Terminal Filaments. | Synapse and Neuromuscular Junction |
What is a Synapse? | a Terminal Filament when joined to a Dendrite of another Neuron |
What is a Neuromuscular Junction? | a Terminal Filament when joined at a Muscle cell |
Define Amitotic. | Cells NOT capable of cell division (replication) - Adult nerve cells |
What are Neuroglia, and where are they found? | they are Supportive Cells found among/AROUND neurons (axons) |
Name 3 types of Neuroglia. | Schwann Cells, Oligodendrocytes, Astrocytes |
What are Schwann Cells and what is their function? | Neuroglia - 1. provide Support and Axon Insulation (myelination); 2. improve SPEED of Nerve Impulses |
Where are Schwann Cells located? | wrapped Around PERIPHERAL Neurons |
What are Nodes of Ranvier? | GAPS between Schwann Cells |
What do Nodes do? | serve as RELAY points for Nerve Impulses |
What are Oligodendrocytes and where are they located? | Neuroglia - wrapped around Central Neurons |
What is the function of Oligodendrocytes? | Their main functions are to provide support and insulation to axons in the central nervous system |
What is the main difference between Schwann Cells and Oligodendrocytes? | Schwann Cells insulate PERIPHERAL Neurons; Oligodendrocytes insulate CENTRAL Neurons |
What are Astrocytes and where are they located? | Neuroglia - Crowded among CENTRAL Neurons |
What are the functions of Astrocytes? | 1. Support and Link neurons to blood Capillaries; 2. regulate Diffusion --. contribute to the Blood-Brain Barrier |
What are the Neuron Functional Types? | Afferent (sensory), Efferent (motor), Interneurons (association) |
What is the function of Afferent Neurons? | impulses travel TOWARD Brain, FROM Sensory receptors in Skin and Organs |
What is the function of Efferent Neurons? | impulses travel AWAY from Brain, into Effectors (muscles/glands) |
What are the functions of Interneurons? | 1. transmit impulses BETWEEN Neurons in the CENTRAL nervous system; 2. help in ANALYSIS of SENSORY input and coordination of MOTOR output |
What are the Neuron Structural Types? | Multi-polar and Unipolar |
Describe a Multi-polar Neuron. | multiple Dendrites; one long Axon - usually in MOTOR function |
Describe a Unipolar Neuron. | one process SPLITS near cell body - usually in SENSORY function |
What is the function of the Presynaptic Neuron? | reacts to Arriving Impulses |
What is the function of Synaptic Vesicles? | Contain/Release Neurotransmitters |
What is the Synaptic Cleft? | narrow GAP between nerve cells |
What is the function of the Postsynaptic Neuron? | reacts to Neurotransmitters |
What is the definition of Transmission? | the Sequence of events in Impulse |
What are the sequences of events involved in Transmission? | Presynaptic impulses --> rupture of Synaptic Vesicles --> release of Neurotransmitter --> new, Postsynaptic impulse(s) |
What is the difference between the CENTRAL Nervous System and the PERIPHERAL Nervous System? | CENTRAL Nervous System: Brain and Spinal Cord; PERIPHERAL Nervous System: Nerve Trunks leading To/From the Brain and Spinal Cord |