My green thumb came only as a result of the mistakes I made while learning to see things from the plant s point of view. -H. Fred Ale Nervous System 1

My green thumb came only as a result of the mistakes I made while learning to see things from the plant s point of view. -H. Fred Ale Nervous System 1

Classroom Rules You'll get one warning, then you'll have to leave the room! Punctuality- Everybody's time is precious: You get here by the start of class, I'll have you out of here on time. Getting back from breaks counts as being late to class. Participation- No distractions: No side talking. No laying down. No inappropriate clothing. No food or drink except water. No phones in classrooms, clinic or bathrooms.

Lesson Plan: 42a Nervous System 1 5 minutes: Breath of Arrival and Attendance 50 minutes: Nervous System 1

Introduction

Introduction The body uses two systems to monitor and stimulate changes needed to maintain homeostasis: endocrine and nervous. Endocrine System Nervous System

Introduction The endocrine system responds more slowly and uses hormones as chemical messengers to cause physiologic changes. Endocrine System 1. Slow response 2. Hormones Nervous System

Introduction The nervous system responds to changes more rapidly and uses nerve impulses to cause physiologic changes. Endocrine System 1. Slow response 2. Hormones Nervous System 1. Rapid response 2. Nerve impulses (and neurotransmitters too)

Introduction It is the nervous system that is the body's master control and communications system. It also monitors and regulates many aspects of the endocrine system. Endocrine System 1. Slow response 2. Hormones Nervous System 1. Rapid response 2. Nerve impulses (and neurotransmitters too) 3. Body control 4. Body communications 5. Monitors and regulates the endocrine system

Introduction Every thought, action, and sensation reflects nerve activity. We are what our brain has experienced. If all past sensory input could be completely erased, we would be unable to walk, talk, or communicate. We would remember no pain or pleasure.

Brain Spinal cord Cranial nerves Spinal nerves Cerebrospinal fluid Meninges Sense organs Neurotransmitters Anatomy

Brain Spinal Cord Nerves

Sensory input Interpretive functions Motor output Higher mental functioning and emotional responsiveness Physiology

Physiology Sensory input Sensory receptors detect changes, or stimuli, inside the body such as lowered blood sugar levels, or outside the body such as an increase in temperature. Receptors carry nerve impulses into the spinal cord and brain.

Physiology Interpretive functions The spinal cord and brain integrate sensory, Information. They analyze it, store some of it, and decide on appropriate responses.

Physiology Motor output Motor neurons carry nerve impulses from the brain and spinal cord to smooth muscle, cardiac muscle, skeletal muscle, and glands.

Physiology Higher mental functioning and emotional responsiveness Examples: cognition, memory, joy, excitement, anger, anxiety.

Nervous System Central N. S. Peripheral N. S. Somatic N.S. Autonomic N.S. Sympathetic N.S. Parasympathetic N.S. Basic Organization

Basic Organization CNS Interpreting sensory info and issuing motor responses PNS PNS Motor or Efferent Neurons Sensory or Afferent Neurons Somatic N.S. Autonomic N.S. Sensory Receptors Effectors ( Muscles and Glands ) Skeletal muscles Cardiac and smooth muscles. Glands

Basic Organization Central nervous system (CNS) Body system primarily concerned with interpreting incoming sensory information and issuing instructions in the form of motor responses. Includes: brain, meninges, cerebrospinal fluid, and spinal cord. Central Nervous System Brain Spinal cord

Basic Organization Peripheral nervous system (PNS) Composed of the cranial and spinal nerves emerging from the CNS.

Brain Spinal Cord CNS in green Nerves PNS in yellow

Basic Organization Somatic nervous system (SNS) Voluntary division of the PNS that transmits information from bones, muscles, joints, skin, and special senses of vision, hearing, taste, and smell into the CNS. Carries impulses from the CNS to skeletal muscles.

Basic Organization Autonomic nervous system (ANS) Involuntary division of PNS supplying impulses to smooth muscle, cardiac muscle, and glands. Has sympathetic and parasympathetic divisions.

Neuroglia Neuron Cells of the Nervous System

Cells of the Nervous System Neuroglia (glia, glial cells) Connective tissue that supports, nourishes, protects, insulates, and organizes neurons. Types: astrocyte, ependymocyte, microglia, oligodendrocyte, Schwann cell, satellite cell.

Cells of the Nervous System Neuron Impulse-conducting cell. Properties: Excitability Conductibility Secretability

Cells of the Nervous System Excitability The ability to respond to a stimulus and convert it to a nerve impulse. Conductibility The ability to transmit the impulses to other neurons, muscles, and glands. Secretability The ability to release neurotransmitters that help conduct an impulse.

Cell body Dendrite Axon Parts of a Neuron

Parts of a Neuron Cell body (AKA: cyton) Main region of the neuron containing the nucleus, ribosomes, and other organelles. The gray matter of the nervous system.

Parts of a Neuron Dendrite Short, narrow, neural extensions that receive and transmit stimuli toward the neuron's cell body.

Parts of a Neuron Axon Neural extension that carries nerve impulses away toward another neuron, a muscle cell, or gland. from the neuron

Telodendria Synaptic bulb Synaptic vesicle Myelin sheath Nodes of Ranvier Axon Structures

Axon Structures Telodendria Clusters of short, fine filaments located at the end of each axon.

Axon Structures Synaptic bulb Small bud-like structure on the ends of telodendria. Contains synaptic vesicles.

Axon Structures Synaptic vesicle Sac-like structure located within the synaptic bulbs that contain neurotransmitters.

Axon Structures Myelin sheath Fatty tissue layer surrounding most axons in the PNS. Insulates the neuron and increases nerve impulse speed.

Axon Structures Nodes of Ranvier Gaps along myelinated axons. Increase speed of a nerve impulse by allowing the impulse to jump from one node to another.

My green thumb came only as a result of the mistakes I made while learning to see things from the plant s point of view. -H. Fred Ale Nervous System 1

My green thumb came only as a result of the mistakes I made while learning to see things from the plant s point of view. -H. Fred Ale Nervous System 2

Endoneurium Perineurium Epineurium Connective Tissues: Neurons to Nerves

Connective Tissues: Neurons to Nerves neuron fascicle nerve endoneurium perineurium epineurium

Connective Tissues: Neurons to Nerves Fascicle (p. fasciculi) Bundles of neurons. Nerve Bundles of fasciculi. Endoneurium Connective tissue layer for a neuron. Perineurium Connective tissue layer for a fascicle. Epineurium Connective tissue layer for a nerve.

Connective Tissues: Neurons to Nerves neuron fascicle nerve endoneurium perineurium epineurium

Sensory neurons (afferent neurons) Interneurons (association neurons) Motor neurons (efferent neurons) Classifications of Neurons

Classifications of Neurons Sensory neuron (AKA: afferent neuron) Carries impulses to the CNS.

Classifications of Neurons Sensory neuron (AKA: afferent neuron) Carries impulses to the CNS.

Classifications of Neurons Interneuron (AKA: association neuron) Nerve between a sensory, and motor neuron. Participates in integrative functions.

Classifications of Neurons Motor neuron (AKA: efferent neuron) Sends a nerve impulse to effectors.

Classifications of Neurons Effector Any muscle or gland that motor nerves act on.

Nerve Impulses Nerve impulse (AKA: action potential) An electrical signal that conveys information along a neuron.

Synapse Presynaptic neuron Postsynaptic neuron Synapse

Synapse Synapse Junction between two neurons or between a neuron and a muscle or gland.

Synapse Presynaptic neuron Neuron carrying a nerve impulse toward a synapse. Postsynaptic neuron Neuron carrying a nerve impulse away from a synapse.

Synaptic bulb Synaptic cleft Cell membrane Synaptic vesicle Synaptic Structures

Synaptic Structures Synaptic bulb Small bulb-like structure on the ends of telodendria. Contains synaptic vesicles.

Synaptic Structures Synaptic cleft (AKA: synaptic gap) Space between the synaptic bulb of the presynaptic neuron and the plasma membrane of the postsynaptic neuron, muscle cell, or gland.

Synaptic Structures Cell membrane (AKA: plasma membrane) Semipermeable membrane that separates cytoplasm from the surrounding external environment.

Synaptic Structures Synaptic vesicle Sac-like structure located within the synaptic bulbs that contains neurotransmitters.

A one-way process Excitatory response Inhibitory response Reuptake Synaptic Transmission

Synaptic Transmission: A one-way process 1. A nerve impulse travels down an axon to a synaptic bulb.

Synaptic Transmission: A one-way process 2. Neurotransmitters travel across the synaptic cleft toward postsynaptic neuron's plasma membrane.

Synaptic Transmission: A one-way process 3. The neurotransmitters bind with receptor sites on the postsynaptic neuron, which brings about either an excitatory or inhibitory response by the postsynaptic neuron depending on which neurotransmitter is being used.

Synaptic Transmission: A one-way process Excitatory response Continuing the impulse. Inhibitory response Stopping the impulse.

Synaptic Transmission: A one-way process Reuptake Drawing up of neurotransmitters in the synapse by the presynaptic neuron.

Neurotransmitters Neurotransmitter Collective term for chemical messengers, involved in nerve impulse transmission. Acetylcholine muscle contraction Epinephrine regulates fight or flight Histamine inflammatory responses Endorphins pain-reduction Etcetera....

My green thumb came only as a result of the mistakes I made while learning to see things from the plant s point of view. -H. Fred Ale Nervous System 2

My green thumb came only as a result of the mistakes I made while learning to see things from the plant s point of view. -H. Fred Ale Nervous System 3

Cranial nerves Spinal nerves Peripheral Nervous System

Peripheral Nervous System Cranial nerve Nerve pairs originating in the brain. 12 total. Mostly supply and control functions of the head, face, and throat. 12 nerve pairs total: 1. Olfactory 7. Facial 2. Optic 8. Vestibulocochlear 3. Oculomotor 9. Glossopharyngeal 4. Trochlear 10. Vagus 5. Trigeminal 11. Accessory or spinal accessory 6. Abducens 12. Hypoglossal

Peripheral Nervous System Spinal nerve Pairs of nerves originating from the spinal cord. 31 pairs total. 31 nerve pairs total: 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal

Cervical nerves Thoracic nerves Lumbar nerves Sacral nerves Coccygeal nerves

Peripheral Nervous System Nerve root Attachment of a spinal nerve to the spinal column. Ventral nerve root Nerve root containing motor neurons. Dorsal nerve root Nerve root containing sensory neurons.

Peripheral Nervous System Ganglion Cluster of nerve cell bodies located in the PNS.

Peripheral Nervous System Plexus Network of intersecting nerves in the PNS.

Peripheral Nervous System Cervical plexus (C1-C5) Plexus that innervates the skin and muscles of the head, neck, and shoulders. Also the diaphragm.

Peripheral Nervous System Brachial plexus (C5-T1) Plexus that innervates the skin and muscles of the upper extremity.

Peripheral Nervous System Lumbosacral plexus (L1-S4) Plexus that innervates the skin and muscles of the abdomen, lower back, genitals, and lower extremity.

Peripheral Nervous System Dermatome Area of skin innervated by a specific sensory nerve root

Peripheral Nervous System Myotome Group of skeletal muscles innervated by a single spinal segment.

Innervate To supply with nerves. Peripheral Nervous System

Peripheral Nervous System Reflex Involuntary, predictable response to a stimulus. Examples: coughing, sneezing, blinking, correcting heart rate, respiratory rate, and blood pressure.

Peripheral Nervous System Reflex arc Nervous system's simplest functional unit. Carries a stimulus impulse to the spinal cord where it connects with a motor neuron that carries the reflex impulse back to an appropriate muscle, or gland (effector). The simplest reflex arc is one sensory neuron and one motor neuron.

Exteroceptor Proprioceptor Interoceptor Receptors Classified by Location of Stimuli

Receptors Classified by Location of Stimuli Exteroceptor Receptor located in the skin, mucous membranes, and sense organs. Responds to stimuli originating from outside of the body.

Receptors Classified by Location of Stimuli Proprioceptor Receptor located in the skin, ears, muscles, tendons, joints, and fascia. Responds to movement and body position.

Receptors Classified by Location of Stimuli Interoceptor Receptor located in the viscera. Responds to stimuli such as digestion, excretion, and blood pressure originating from within the body.

Receptors Classified by Location of Stimuli Adaptation Decrease in sensitivity due to prolonged stimulus.

Chemoreceptor Mechanoreceptor Etcetera... Receptors Classified by Location of Stimuli

Receptors Classified by Type of Stimuli they Detect Chemoreceptor Activated by chemical stimuli. Detects smells, tastes, and changes in blood chemistry. Mechanoreceptor Receptor that detects pressure and movement. Found in the skin, blood vessels, ears, muscles, tendons, joints, and fascia. Detects pressure, blood pressure, vibration, stretching, muscular contraction, proprioception, sound, and equilibrium.

Receptors Classified by Type of Stimuli they Detect Pressure receptor Receptor that detects pressure in skin and mucous membranes. Examples: Meissner corpuscle, Ruffini corpuscle, Pacinian corpuscle, Krause end bulbs, Merkel disks, and hair root plexus.

Receptors Classified by Type of Stimuli they Detect Stretch receptor Receptor that detects stretch in muscle fibers, tendons, and arteries. Examples: muscle spindle, Golgi tendon organ, and baroreceptor.

Receptors Classified by Type of Stimuli they Detect Muscle spindle Stretch receptor located within the muscle belly. Detects sudden stretching, causing the nervous system to respond by reflexively contracting the muscle.

Receptors Classified by Type of Stimuli they Detect Golgi tendon organ Receptor located at the musculotendinous junction. Detects tension and excessive stretch, causing the nervous system to respond by inhibiting contraction.

Receptors Classified by Type of Stimuli they Detect Baroreceptor Receptor that detects blood pressure by monitoring the amount of stretch exerted on certain arterial walls, namely carotid arteries and the aortic arch.

Receptors Classified by Type of Stimuli they Detect Photoreceptor Receptor that is sensitive to light. Examples: rods and cones in the eyes.

Receptors Classified by Type of Stimuli they Detect Nociceptor (AKA: free nerve ending) Receptor that detects pain.

Receptors Classified by Type of Stimuli they Detect Thermoreceptor Receptor that detects temperature changes.

My green thumb came only as a result of the mistakes I made while learning to see things from the plant s point of view. -H. Fred Ale Nervous System 3