What are the 2 Major Sections of the Nervous System?
1. Central NS: Brain and Spinal Cord 2. Peripheral NS: All other nervous tissue
90
New cards
What are the 3 functions of the Nervous System? / Neural Pathway
1. Sensory Function: Receptors in PNS detect stimuli, sensory info is transmitted to the CNS via a sensory neuron 2. Integrative Function: CNS integrates info, and decides on an outcome 3. Motor Function: CNS transmits motor response to the PNS via a motor neuron, action is carried out by effectors
91
New cards
What are the 3 sections of the PNS?
* Somatic NS: In charge of voluntary actions, including touch, pressure, pain, temperature and stretch. Includes special sensors. Has 2 Divisions * Sensory Division: Receptors in skeletal muscle, joints, and special sensors relay information TO CNS * Motor Division: Response FROM the CNS is transmitted to skeletal muscle, joins and special sensors
\ * Autonomic NS: In charge of automatic processes, including breathing, heartbeat, digestion and hormone release. Has 2 divisions: * Sensory Division: Receptors in autonomic organs and glands transmit information TO the CNS * Motor Division: Response FROM the CNS is transmitted to autonomic organs and glands * Also has 2 classifications: Sympathetic (fight or flight) and Parasympathetic (rest or digest)
\ * Enteric NS: Newer classification, in charge of nervous tissue in the gut. Has 2 sections: * Sensory Division: Receptors in the GI tract transmit information TO the CNS * Motor Division: Response FROM the CNS to the smooth muscle cells, glands and endocrine cells in the GI (AUTONOMIC)
92
New cards
List the 6 Structures of the Neuron and their Functions.
* Cell Body / Soma: Contains nucleus, cytoplasm and organelles, and receives and integrates information from receptors and other neurons * Dendrites: Projects off the cell body, receives information from other cells to take into cell body, and are the site of input for neurons * Axon: Tube coming off cell body, carries AP away from the cell, propagates it towards another neuron or effector * Axon Terminal: Comes off the end of the axon and connects to other cells to transmit electrical impulses /AP * Synaptic End Bulbs: The swollen ends of the axon terminal where neurotransmitters are stores * Myelin Sheath: Made of Schwann cells, covers the axon to keep electrical impulses inside, and increases the speed of electrical impulse transfer
93
New cards
Draw and Label a Neuron
94
New cards
What are the 3 structural classifications of the neuron?
* Multipolar: Several dendrites, single axon, makes up most of CNS neurons and all motor neurons * Bipolar: Single main dendrite, single axon, for special sensors * Unipolar: Dendrites and axon are fused as a continuous process, cell body is to the side
95
New cards
What are the 3 functional classifications of neurons?
* Afferent / Sensory * Efferent / Motor * Interneuron: Transmits information between afferent and efferent neurons, only in the CNS
96
New cards
What is a neuroglia?
All other nervous tissue except neurons.
97
New cards
What are the 4 types of Neuroglia in the CNS?
1. Astrocytes: Star-shaped, maintain optimum chemical environment in the BBB 2. Oligodendrocytes: Octupus-like, wrap around axon, form and maintain myelin sheath in the CNS. 3. Microglia: Small, spine-like processes, act as phagocytes by removing damaged tissue, trigger further immune response, it also destroys damaged tissue in CNS. 4. Ependymal: cuboidal cells with microvilli and cilia, lines ventricles and central canal and produce and circulate cerebral spinal fluid.
CAOME (Can’t always offer meals everybody!)
98
New cards
What are the 2 PNS neuroglia?
1. Satellite cells: surround cell bodies on neurons of PNS ganglia for structural support, exchange materials from cells bodies and interstitial fluid. 2. Schwann cells: Form myelin sheath in PNS, each cell myelinated a single axon.
99
New cards
What is neuroregeneration?
Growth and repair of nervous tissue and cells.
* In the CNS, there is little neuroregeneration, due to inhabitory influences from neuroglia, and rapid formation of scar tissue * In the PNS, neuroregeneration occurs if cell body is intact, Schwann cells are functional, and scar tissue doesn’t rapidly form. The steps are: * -
100
New cards
What are the 6 collections of nervous tissue?
Clusters of neuron cell bodies
* Ganglion (PNS) * Nucleus (CNS)
Bundle of Axons
* Nerve (PNS) * Tract (CNS)
White and Grey Matter
* White (Myelinated axons) * Grey (Neurons, cell bodies, unmylinated axons, axon terminals, and neuroglia)