Nervous & Endocrine System: These two body systems work together to maintain homeostasis within the body Life Process: regulation Corresponding cell organelle: nucleus Targets: What are the functions of the nervous system? How is the nerve impulse transmitted?

THE NERVOUS SYSTEM Song https://www.youtube.com/watch?v=ivk_irrH1WY

A. Function: To Control & Coordinate the bodies responses to changes in the environment B. Why? Homeostasis is constantly being threatened. Failure to respond may result in disease or death C. How? Uses neurons to send electrical messages (impulses) throughout the body

A. Stimulus and Response Stimuli is a change in the internal or external environment of the body Receptors are used to detect stimuli (sensory organs ie. ears, skin, nose, etc) Response is the way you react to a certain stimuli Effectors are organs or muscles that produce the response Stimuli Response Bright light Hunger Wasp or bee Eyes Blink and/or squint Mouth Salivates, stomach growls Use muscles to swat or move away

B. Neurons: (a.k.a. nerve cells) nerve cells specialized for receiving and transmitting electrochemical signals called an impulse functioning units of the nervous system Video http://www.brainpop.com/health/bodysystems/neurons/

1. Nerve cell (neuron) “DCATS” – order of impulse SYNAPSE T T S 1 = dendrite Detects stimulus & generates an impulse towards the cyton 2 = cyton (cell body) Contains the nucleus of the neuron 3 = axon (covered by myelin sheath) A long fiber that carries the impulse away from the cell body and towards the terminal branches Myelin sheath insulates/protects the axon 4 = end brushes (a.k.a: Terminal branches) Secrete neurotransmitters (chemical messengers) Impulse is transmitted to the next neuron across the synapse

Nerve Cell Communication: The shape of the neurotransmitter must fit the shape of the cell receptor. Between 2 neurons (nerve cells) is a space, or a gap, called the synapse Neurotransmitter: Chemicals used to help transfer the impulse across the synapse; shape specific Nerves: bundle of neurons that transmits impulses

How does an impulse (an electrochemical signal) travel from one neuron to the next?  The shape of the neurotransmitter must fit the shape of the cell receptor. This is an example of specificity

Types of neurons a) Sensory From sense organs to brain/spinal cord b) Interneurons Found in brain and spinal cord Btwn sensory & motor neurons c) Motor From brain/spinal cord to muscles/glands sensory neuron (from senses) interneuron (brain & spinal cord) motor neuron (to muscle)

Reflex Arc (Loop): Quick involuntary action; it doesn’t involve the brain Neurons may release chemicals to stimulate each other, or these chemicals may be released to stimulate a muscle or gland.  An example of a muscle being stimulated by a neuron appears after the reflex path pictured in number four in the diagram. Receptor Effector “RSIME”- order of impulse in reflex loop R- RECEPTOR (DETECTS STIMULUS)- ex. SENSORY ORGAN S- Sensory neuron I- INTERNEURON m- MOTOR NEURON E- EFFECTOR (RESPONDS TO STIMULI)- ex. MUSCLE OR GLAND

C. Divisions of the Nervous System divided into 2 main parts: The Central Nervous System (CNS) The Peripheral Nervous System (PNS) Targets: What are the functions of the central nervous system? What are the functions of the two divisions of the peripheral nervous system?

Mirror neurons (14 :00) - http://www. pbs

The Brain Pons Section 35-3 Thalamus Pineal gland Cerebellum Pituitary gland Hypothalamus Cerebrum Medulla oblongata Spinal cord Cerebellum Pineal gland Thalamus

1. Central Nervous System (CNS) Consists of the Brain and Spinal Cord Wrapped up in tissue layers called meninges. Cerebrospinal fluid “bathes” them and protects the brain and spinal cord. cerebrum: center for voluntary activity interprets sensory impulses, initiates some motor activities, and responsible for memory, thinking and reasoning cerebellum: coordinates motor activities and aids in maintaining balance medulla: controls involuntary activities such as breathing, heartbeat, blood pressure and peristalsis (is part of the brain stem)

2. Peripheral Nervous System (PNS) Consists of spinal nerves (not the brain or spinal cord). Sensory division: transmits impulses from sense organs to the CNS. B. Motor division: transmits impulses from the CNS to muscles or glands. Somatic Nervous System: Regulates activities that are under conscious control, such as movement of muscles. Autonomic Nervous System: Regulates activities that are automatic or involuntary, such as heartbeat and digestion. Pearson activity and coloring CNS WS

D. Nervous System Disorders Very serious; the nervous system CANNOT repair itself Stroke Results from a cerebral hemorrhage or blood clot in a cerebral BV blocking blood flow to brain 2. Parkinson’s Disease Loss of the functioning of a particular group of nerve cells in brain; missing dopamine (neurotransmitter) Triggered by environmental factors and/or Genetic tendency Symptoms: Shaking, Poor balance, Lack of coordination, Stiffening of Muscles Michael J Fox Parkinson's Disease (2:13) https://www.youtube.com/watch?v=ECkPVTZlfP8 Scientific American Frontiers - Season 3 Prescription poison start time 15:20 3. Alzheimer’s Progressive degenerative disease interferes w/ brain neurons causing cognitive problems Symptoms are memory loss, Inability to think, speak or care for oneself Of Mice and Memory (12:16)- Alzhemiers http://www.pbs.org/wgbh/nova/sciencenow/0301/02.html

5. Multiple Sclerosis 4. Meningitis inflammation of the meninges (brain & spinal cord tissue); can be viral or bacterial (is more serious) Viral (viruses): includes Enteroviruses, Herpes, Mumps ,Varicella (chickenpox), Measles, Rubella and, West Nile virus Bacterial: Bacteria enter upper respiratory system, then the bloodstream and travels to the brain; can die within hours Video Meningitis Threatens Students (3:40) Meningitis http://www.nbcnews.com/id/20519953/ns/health-infectious_diseases/t/killer-college-meningitis-threatens-students/#.VNjZafMo7cs 5. Multiple Sclerosis Cells in the brain and spinal cord do not function properly due to destruction of myelin sheath Symptoms: Shaking of hands, blurred vision, Slurred speech, Muscle weakness, and Loss of bladder control