Human Anatomy 2300--Intro to the Nervous System
Human Anatomy 2300--Intro to the Nervous System Anatomy 2300
Popular in Human Anatomy
Popular in Anatomy
This 3 page Class Notes was uploaded by Isabella Bowling on Friday June 3, 2016. The Class Notes belongs to Anatomy 2300 at Ohio State University taught by Dr. Burgoon in Spring2015. Since its upload, it has received 17 views. For similar materials see Human Anatomy in Anatomy at Ohio State University.
Reviews for Human Anatomy 2300--Intro to the Nervous System
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 06/03/16
Anatomy 2300Lec#9 INTRO TO THE NERVOUS SYSTEM Nervous System --Functions 1. Gathers info or sensory input via sensory receptors 2. Through integration, it processes and interprets the sensory input and decides what, if any, action should be taken. 3. It produces a response or motor output, activating effector organs. --Divisions 1. Central Nervous System (CNS) --Composed of the brain and spinal cord. --Integrative and control centers of body 2. Peripheral Nervous System (PNS) --Composed of all nervous structure outside of the brain and spinal cord…. Such as cranial nerves (originate from the spinal cord), ganglia (groups of neuron cell bodies not in CNS), and plexuses (intermingling of neuron cell process from ventral rami of different cord levels). --Communication lines between the CNS and the rest of the body. --A nerve is a collection of nerve axons found in the PNS. --Cellular components of Nervous tissue 1. Neuroglia, Glia, or supporting cells… much smaller than neurons and help the neurons do their job. --6 types… 4 in CNS, 2 in PNS --CNS: Astrocyte, Microglial, Ependymal, and Oligodendrocyte --PNS: Schwann cells and sensory neurons --Oligodendrocytes produce Myelin sheaths for the CNS while schwann cells do the same for the PNS. Allow action potentials to travel faster. 2. Neurons… excitable, functioning cells that can transmit action potentials for communication. --Basic structure of neurons 1. Cell body… contains the organelles and nucleus of the cell. Biosynthetic center of neuron. 2. Axon… a process that conducts nerve impulses down the cell to pass along the signal. The conducting region. Also called the nerve fiber. One way signal away from body to terminals. 3. Dendrites… a process that functions to receive input from environment. Can be multiple. 4. Axon Terminals… processes that function to affect other neurons or other cells as it releases chemicals to effect other cells. Can be multiple. Types of Neurons --Three types based on structure… based on # of processes connected to the cell body 1. Multipolar neurons 3 or more processes. Can either be motor OR interneuron. 2. Bipolar neurons 2 processes. Rarest of the three types. Are sensory neurons. 3. Unipolar neurons 1 process. Connects to the axon of another cell. Are sensory neurons. --Three types based on function… based on the impulse’s direction of travel relative to CNS 1. Sensory or Afferent neurons towards CNS 2. Motor or Efferent neurons away from CNS 3. Interneurons or Association neurons found between motor and sensory neurons. Nerves --A nerve is a collection of nerve axons/fibers found in the PNS. --Composition 1. Neuron processes (specifically axons/fibers) 2. Myelin 3. Connective tissue --Tissue coverings associated with nerves 1. Endoneurium… covers one neuron fiber (w/ or w/o myelin) 2. Perineurium… covers a group of neuron fibers called a fascicle 3. Epineurium… covers groups of fascicles with blood vessels into a group. 4. Blood vessels 5. Lymphatic vessels. --Classification of nerves --Based on direction… which way they transmit their impulses 1. Sensory (afferent) nerves contains only sensory fibers; transmit nerve impulses only towards the CNS 2. Motor (efferent) nerves contains only motor fibers; transmit nerve impulses only away from the CNS 3. Mixed nerves contain both sensory and motor fibers; the sensory fibers transmit nerve impulses only toward the CNS, while the motor fibers transmit nerve pulses only away from the CNS. MOST COMMON TYPE. --Based on origin… where they originate 1. Cranial nerves originate at the brain; 12 pairs. 2. Spinal nerves originate at the spine; 31 pairs. --8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal --Spinal nerve formed from the union of a dorsal root (containing afferent fibers) and a ventral root (containing efferent fibers). --Splits into a dorsal and ventral ramus once it leaves the vertebrae. Both of these are mixed with sensory and motor fibers. --Dorsal rami serve to bring info from the back and send info to the back muscles. Ventral rami serve to do form plexuses… a. Cervical plexus C1—C4 b. Brachial plexus C5—T1 (part) -- T1(part)—T12 don’t form a plexus. c. Lumbar plexus T12—L4 d. Sacral plexus L4—S4 --Plexuses allow new nerves to form. No synapses in plexuses, but it’s a reorganization to form the new nerves. Regrouping allows the complete paralysis of one limb to be eliminated, if one spinal nerve is damaged, so if something happens to one group, the muscle will still work (even if it’s not strong).
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'