1. Reflex and autonomic nervous system The peripheral nervous system

2. Remember  The nervous system is divided into 2 portions  The central nervous system  The peripheral nervous system  The 2 systems are connected  12 pairs of cranial nerves connect with the brain  31 spinal nerves connect CNS to the rest of the body.

3. Nerves  Bundles of axons & dendrites of neurons.  Spinal nerves have:  A dorsal root: caries messages TO CNS from sensory receptors  A ventral root: Carries messages FROM CNS to motor neurons.  Carry massage to muscles and glands  Interneurons: relay information between neurons.

4. Sensory division  Has sensory receptors that collect information form internal and external environments.  The information is passed on to the central nervous system. Pair share: name 2 things that the sensory receptors might collect from the internal and external environment.

5. Motor division  The body’s way of reacting to the sensory information.  Has independent systems:  Somatic  Autonomic

6. Somatic nervous system  Controls the movement of skeletal muscles.  Has both voluntary and involuntary components.  Voluntary is under conscious control  Involuntary maintains balance  Includes reflexes: signals that go to 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.

7. Autonomic Nervous System  Controls internal organs and glands, everything that is involved in maintaining homeostasis.  Ex: heart beat, pupils of the eye, blood vessels, and adrenal glands.

8. Subdivisions of the Autonomic system  Sympathetic: stimulates the body (stress response).  Example: redirects blood from digestive system to muscles and heart  Parasympathetic: maintains body under normal conditions.  Example: signals body to return to normal activity

10. White board Review 1.What are the 2 sections of the peripheral nervous system 2.What does the somatic nervous system regulate? 3.What is the difference between the sympathetic and parasympathetic divisions of the autonomic system?