The Nervous System.pdf

The Nervous System  Objectives Students will be able to: describe the simplicity of a reflex. describe the nervous system’s 2 major divisions. identify the subdivisions of the peripheral nervous system and describe their functions.  This is a neuron, the building block of the...

The Nervous System  Objectives Students will be able to: describe the simplicity of a reflex. describe the nervous system’s 2 major divisions. identify the subdivisions of the peripheral nervous system and describe their functions.  This is a neuron, the building block of the nervous system. There are 86 billion in the brain alone! Afferent: sensory Efferent: motor A Simple Reflex The Nervous System Afferent Efferent Neurons (Nerve cells) Sensory (afferent) – carries incoming info from sensory receptors to the brain and spinal cord Interneurons – within the brain and spinal cord that communicate between sensory inputs and motor outputs Motor (efferent) – carries outgoing info from brain and spinal cord to muscles and glands Central NS Peripheral NS The Nervous System  Autonomic Nervous System Sympathetic NS “Arouses” (fight-or-flight) Parasympathetic NS “Calms” (rest and digest)