Nervous+System.ppsx

NERVOUS SYSTEM Chapter 9 http://www.youtube.com/watch_popup?v=xdj67XknFrM# t=5 Objectives  Describe the anatomy of the nervous system  Central nervous system  Peripheral nervous system  Microscopic anatomyneuron  Anatomy of the Brain  Cranial Nerves  Focus on Sympathetic and Parasympatheti...

NERVOUS SYSTEM Chapter 9 http://www.youtube.com/watch_popup?v=xdj67XknFrM# t=5 Objectives  Describe the anatomy of the nervous system  Central nervous system  Peripheral nervous system  Microscopic anatomyneuron  Anatomy of the Brain  Cranial Nerves  Focus on Sympathetic and Parasympathetic function and effects 3 Basic Functions  Sensory Function  Integrating Function  Motor Function The BOSS  Nervous system is the rapid response, “boss of bosses” Communication & control system Monitors what is going on inside & outside of the body Directing the bodies activities to correspond  Understanding the nervous system helps us to understand: Nervous System  Consists of: Central nervous system (CNS) ○ Brain & Spinal cord Peripheral Nervous system (PNS) ○ encompasses nerves outside the brain and spinal cord. Links the CNS with the rest of the body ○ Nerves that extend away from the brain, spinal cord How it Functions  Receive information from the environment  Analyzes the information  Respond appropriately Neuron  High O2 requirements- during CPR it is important that the brain, neurons receive oxygen  Neurons are unable to reproduce- spinal injuries, able to regenerate if the cell remains intact  Have the same structural components as other cells-shape is adapted for their function  Involved in the transmission of impulses over long distances –long, thin cells with branching connections  Neuron can look physically different depending on their location in other parts of the body. But basic structure is the same Parts of a Neuron Functional unit of the nervous system consists of:  Cell body (soma) ○Nucleus ○Dendrites ○Axon  Myelin sheath  Synapse a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter. Examples of Neurotransmitters        Acetylcholine Dopamine gamma-aminobutyric acid (GABA) glutamate histamine Norepinephrine Epinephrine* Serotonin Nervous System  Central Nervous System  Peripheral Nervous System  Somatic nervous system-voluntary  Autonomic nervous system-involuntary  Tissue of the CNS consist of: Grey matter White matter Brain  Divided into four sections Cerebrum Cerebellum Diencephalon Brain stem http://vanat.cvm.umn.edu/grossbrain/ Cerebrum     Receives and interprets sensory information Initiates nerve impulses to the muscles Integrates neuron activity that is associated with conscious activity Divided into hemispheres (right and left) by the longitudinal fissure  Each hemisphere is divided into lobes (i.e., frontal, parietal, occipital, temporal) Appearance  Gray matter (cerebral cortex) Outer membrane  White matter Largest part of the mammalian brain Higher order functions  Gyri or gyrus Sulcus ○ Fissures  Lobes Cerebellum  Second largest portion of the brain  Allows the body to have coordinated movement, balance, posture and complex reflexes  Control the accuracy of movements Diencephalon    Pathway between the brain stem and cerebrum Not as physically defined as the other parts Three structures associated with the diencephalon are: Thalamus Hypothalamus Pituitary Brain Stem  Connection between brain and spinal cord  Involved in autonomic control functions of the heart, respiration, blood vessel diameter, swallowing and vomiting  Many of the cranial nerves originate from this area  Composed of: Medulla oblongata Pons Midbrain Protection of the Brain  Skull Bones  Meninges Connective tissue that surrounds the brain and spinal cord Responsible for providing blood vessels and cushioning  Three layers Dura mater Arachnoid Pia mater  Cerebral Spinal Fluid (CSF) Spinal Cord  Runs from the medulla oblongata to the lumbar region of the vertebral column  Spinal cord is segmented  Each segment corresponds to a particular vertebrae  Cauda equina-7th lumbar vertebrae Spondylosis Peripheral Nervous System  Nerves from the brain and spinal cord  Form the communication network between the CNS and the body parts  Nerves are classified according to the organs they supply and the direction they run Types: Sensory-impulses toward the CNS ○ From sensory receptors in the skin and elsewhere Motor-Away from the CNS ○ Out toward the muscles Mixed Efferent-Away from the CNS out toward muscles & other organs Afferent/Motor-impulses toward the CNS Visceral-sensory & motor ○ Organs ○ Somatic-sensory & motor Skin or muscoskeletal https://www.osmosis.org/answers/affere nt-vs-efferent-neurons Cranial Nerves      Part of the PNS I-XII Chart page 243 Nerves that come from the brain and leave the cranium through the numerous foramen Names often reflect their function Autonomic Nervous System  PNS  Involuntary  Self regulating system Contraction of the intestines Regulation of the heart rate Blood pressure  Sends impulses to smooth muscle, cardiac muscle and endocrine glands  Subdivided into Sympathetic and Parasympathetic divisions Parasympathetic and Sympathetic Nervous Systems  These two system generally have opposite effects  Sympathetic nerves emerge from the thoracic and lumbar vertebra  Parasympathetic emerges from the brain and spinal cord Sympathetic System  Fight or Flight Page 246  It has a excitatory effect Increases breathing Increases heart rate Decrease GI secretions Dilates pupil Parasympathetic  Rest and restore system Decreases the excitatory effects  Helps the body replace its losses during the fight or flight mode Increases GI motility Decreases heart rate Restore respiratory rate to normal Constricts pupils Drugs or Diseases  May stimulate, imitate, or inhibit the signs of the sympathetic or parasympathetic nervous systems Review         What type of system is the nervous system; list some characteristics of the nervous system List the functions of the nervous system What is the functional unit of the nervous system CNS is comprised of what organs Is it voluntary or automatic What are the four parts of the brain and their importance List some characteristics of the Spinal Cord What is the sympathetic and parasympathetic nervous system and their significance