3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Essential Question What are the structures of the nervous system? 3.01 Remember the structures of the nervous system

Introduction: Structures of the nervous system 3.01 Remember the structures of the nervous system

Cellular structures of the nervous system Neuron- a nerve cell Extensions of the neuron Dendrites - many Axon - one 3.01 Remember the structures of the nervous system

Cellular structures of the nervous system Neuron- a nerve cell Myelin sheath - a special covering of the axon ( it speeds up the impulse along the axon) Produces a fatty substance called myelin to protect the axon Synapse – the space between neurons (messages go from the axon of 1 cell to the dendrite of another) 3.01 Remember the structures of the nervous system

Membrane Excitability Nerves carry impulses by creating electric charges Neurons have a membranes that separate its cytoplasm inside from extracellular fluids outside Neuron has a lot of K+ but little Na+; opposite of extracellular fluid; membrane allows for these ions to move in and out of the cell 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Membrane Potential Resting: More positive ions (K+ has moved outside the cytoplasm) on the outside of the membrane (ready for action) Depolarization: A stimulus is initiated (i.e. sound) that converts to electrical charge which allows the “gated” Na+ ions to come into the cytoplasm (action potential) Repolarization: the neuron closes to allow no more Na+ but opens the K+ gates to allow it to escape thus sending it back to a positive outside and a negative inside 3.01 Remember the structures of the nervous system

Structures of the nervous system Central nervous system Brain- cerebral cortex (outer) highest center of reasoning & intellect Spinal cord 3.01 Remember the structures of the nervous system

Structures of the nervous system Peripheral nervous system Nerves Cranial nerves Spinal nerves Sensory receptors 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Cerebrum: largest part of the brain Divided into two hemispheres (right and left) by a deep groove called the longitudinal fissure Frontal lobe Occipital lobe Parietal lobe Temporal lobe 3.01 Remember the structures of the nervous system

Frontal Lobe & Temporal Lobe Controls voluntary muscle movement Controls speech in the left hemisphere (Broca) Cells in R hemisphere control movements on L side of the body and vice-versa Temporal Anterior portion is smell and the rest is hearing Wernicke area: central language area for speech understanding & comprehension 3.01 Remember the structures of the nervous system

Parietal & Occipital Lobes Behind the frontal lobe and it is your sensory center Where you feel pain, touch, heat, cold, and balance Occipital Over the cerebellum, visual area that controls eyesight 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Diencephalon Located between the cerebrum and the midbrain Structures Thalamus Hypothalamus Pineal body Pituitary gland 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Diencephalon Pineal Body- produces melatonin below the 3rd ventricle Pituitary Gland-size of a grape, base of brain at the depression of the sphenoid bone; connected to hypothalamus; hormones of pituitary are controlled by hypothalamus 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Diencephalon Thalamus – spherical mass of gray matter; deep in the cerebral hemispheres; relay station for incoming & outgoing nerve impulses Hypothalamus – lies below the thalamus; part of the limbic system; the “brain” of the Brain Autonomic Nervous Control Cardiovascular (BP, constriction & dilation of vessels and heart beat) Sleep control 3.01 Remember the structures of the nervous system

Hypothalamus continued Temperature maintains 98.6 Appetite control- gives you signals when you are hungry & when to stop eating Water balance-high osmotic pressure in blood signals water deficiency & ADH is secreted Manufacture oxytocin-contracts uterus in labor GI control- increases peristalsis Emotional State- fear & pleasure Mind over body experiences- when patients given terminal diagnosis but are able to will themselves well 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Limbic system Located in the center of the brain Encircles the top of the brain stem. Olfactory bulb-relates food with emotions Amygdala-emotional reactor (fear, anxiety, aggression Hippocampus-memory & learning 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Limbic system Parahippocampus: monitors strong emotions like rage & fright Fornix: pathway of nerve fibers from hippocampus to mammillary body Mammillary Body: nucleus transmits messages between fornix & thalamus Cingulated Gyrus: Modifies Behavior & emotion Septum pellucidum: connects fornix to corpus callosum 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Cerebellum Controls anything regarding movement of skeletal muscles Maintenance of balance Maintenance of muscle tone Coordination of muscle movements 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Brain stem-has gray matter & neurons responsible for sleep-wake cycle; damage to certain area can cause coma Midbrain-location of cerebral aqueduct assists w/ vision & hearing Pons-2 way path for incoming and outgoing impulses for both the cerebrum & cerebellum; site of 4 cranial nerves & a respiratory control center Medulla oblongata-white matter on outside serves as message center between brain & spinal cord; responsible for basic body functions as breathing and heart beat 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Meninges Dura mater Outermost layer- Lines inside of skull; tough fibrous material that has an abundant amount of blood vessels Arachnoid Middle layer- cobweb of fluid filled spaces Pia mater Innermost layer- covers the brain surface itself CSF fills space between arachnoid and pia mater (produced within the ventricles & is our brain’s shock absorber) 3.01 Remember the structures of the nervous system

Structures of the central nervous system: BRAIN Ventricles - lined cavities deep within the brain filled with cerebrospinal fluid Choroid plexus – rich network of blood vessels in all 4 ventricles of the brain; aids in formation of CSF Is selective in its ability to allow certain things to pass through (blood brain barrier) 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Brain Teasers 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system What word do you see? Read aloud 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Can you read this? 3.01 Remember the structures of the nervous system

Structures of the central nervous system: Spinal Cord Surrounded by the vertebrae, meninges, and cerebrospinal fluid 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Spinal Cord Anatomy Grey Matter: route sensory or motor stimulus to interneurons of the CNS in order to create a response to the stimulus through chemical synapse activity. White Matter: It contains nerve fibers. Many of these nerve fibers (axons) are surrounded by a type of fat called myelin. The myelin gives the white matter it's color. Myelin acts as an insulator. It plays an important role in the speed of nerve signaling. 3.01 Remember the structures of the nervous system

Structures of the peripheral nervous system: Afferent peripheral nerve system: sensory neurons that send info from receptors in the periphery of the body to the brain & spinal cord Efferent peripheral Nerve System: motor neurons send info from brain & spinal cord to muscles & glands Somatic: impulses from CNS to skeletal muscles (voluntary) Autonomic: impulses from CNS to smooth muscle (involuntary) 1. Sympathetic: “fight or flight” 2. Parasympathetic: “rest & digest” 3.01 Remember the structures of the nervous system

Structures of the peripheral nervous system I. Olfactory II. Optic III. Oculomotor IV. Trochlear V. Trigeminal VI. Abducens VII. Facial VIII. Vestibulocochlear IX. Glossopharyngeal X. Vagus XI. Accessory XII. Hypoglossal Cranial nerves 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Structures of the PNS Peripheral nervous system 31 pairs of spinal nerves Named by location in the spinal cord (plexus: network of nerves in spine) Cervical Plexus (C1-C4): mvmt of shoulders & neck Brachial plexus (C5-8, T1): mvmt shoulder, wrist & hands Lumbar Plexus (T12, L1-4): mvmt of buttocks, anterior thigh & leg Sacral Plexus (L4-5, S1-2): motor mvmt leg (sciatic nerve: lgst nerve in body—gluteus maximus to knee) 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Structures of the PNS Anterior View Peripheral nervous system 12 cranial nerves 31 pairs of nervous Posterior view 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Structures of the PNS Motor system Autonomic nervous system Sympathetic nervous system Parasympathetic nervous system Somatic nervous system 3.01 Remember the structures of the nervous system

Structures of the PNS Autonomic nervous system Sympathetic nervous system Extends from the base of the brain, along both sides of the spinal column These nerves connect to all internal organs Parasympathetic nervous system The vagus nerve connects the medulla with organs of the upper body The pelvic nerve emerges from the spinal cord and connects with the organs of the lower body 3.01 Remember the structures of the nervous system

Structures of the PNS Somatic nervous system These nerves are located along the spinal cord. Connect skeleton, muscles and joints to the brain. 3.01 Remember the structures of the nervous system

Structures of the CNS & PNS Check your knowledge… 3.01 Remember the structures of the nervous system

Structures of the nervous system Remember this! 3.01 Remember the structures of the nervous system

3.01 Remember the structures of the nervous system Essential question What are the structures of the nervous system? 3.01 Remember the structures of the nervous system