Reflex and autonomic Reflex and autonomic nervous systemnervous system

The peripheral nervous systemThe peripheral nervous system

RememberRemember

The nervous system is The nervous system is divided into 2 portionsdivided into 2 portions The central nervous systemThe central nervous system The peripheral nervous systemThe peripheral nervous system

The 2 systems are connectedThe 2 systems are connected 12 pairs of cranial nerves 12 pairs of cranial nerves

connect with the brainconnect with the brain 31 spinal nerves connect CNS 31 spinal nerves connect CNS

to the rest of the body.to the rest of the body.

NervesNerves Bundles of axons & dendrites of Bundles of axons & dendrites of

neurons.neurons. Spinal nerves have:Spinal nerves have:

A dorsal rootA dorsal root: caries messages TO : caries messages TO CNS from sensory receptorsCNS from sensory receptors

A ventral rootA ventral root: Carries messages : Carries messages FROM CNS to motor neurons.FROM CNS to motor neurons. Carry massage to muscles and glands Carry massage to muscles and glands

Interneurons: relay information Interneurons: relay information between neurons. between neurons.

Sensory division Sensory division

Has sensory receptors that collect Has sensory receptors that collect information form internal and external information form internal and external environments.environments.

The information is passed on to the The information is passed on to the central nervous system.central nervous system.

Pair share: name 2 things that the sensory receptors might collect from the internal and external environment.

Motor divisionMotor division

The body’s way of The body’s way of reacting to the sensory reacting to the sensory information.information.

Has independent Has independent systems:systems: SomaticSomatic Autonomic Autonomic

Somatic nervous systemSomatic nervous system

Controls the movement of Controls the movement of skeletal muscles.skeletal muscles.

Has both Has both voluntaryvoluntary and and involuntaryinvoluntary components. components. Voluntary is under conscious Voluntary is under conscious

controlcontrol Involuntary maintains balanceInvoluntary maintains balance

Includes Includes reflexesreflexes: signals that go to : signals that go to the spinal column but not the brain.the spinal column but not the brain.

Pair share: Give a reason why it is important for the body to have both voluntary and involuntary functions of the nervous system .

Autonomic Nervous Autonomic Nervous SystemSystem

Controls internal Controls internal organs and glands, organs and glands, everything that is everything that is involved in involved in maintaining maintaining homeostasis.homeostasis. Ex: heart beat, pupils Ex: heart beat, pupils

of the eye, blood of the eye, blood vessels, and adrenal vessels, and adrenal glands.glands.

Subdivisions of the Subdivisions of the Autonomic systemAutonomic system

SympatheticSympathetic: stimulates the body (stress : stimulates the body (stress response).response). Example: redirects blood from digestive Example: redirects blood from digestive

system to muscles and heartsystem to muscles and heart

ParasympatheticParasympathetic: maintains body under : maintains body under normal conditions. normal conditions. Example: signals body to return to normal Example: signals body to return to normal

activity activity

White board ReviewWhite board Review1.1. What are the 2 What are the 2

sections of the sections of the peripheral nervous peripheral nervous systemsystem

2.2. What does the What does the somatic nervous somatic nervous system regulate?system regulate?

3.3. What is the difference What is the difference between the between the sympathetic and sympathetic and parasympathetic parasympathetic divisions of the divisions of the autonomic system?autonomic system?