1. Six Divisions of Nervous System
Somatic Nervous System
The group of nerves in the peripheral nervous system that controls voluntary actions. Controls voluntary movements Carries messages from the sensory receptors in the body to CNS & motor messages from CNS to skeletal muscles. Has a sensory function AFFERENT TRACT (carrying info from sense organs in body to the CNS -> sensory neurons via the interneurons in the spinal cord then to the brain). Also has a motor function EFFERENT TRACT (carrying information away from the CNS to the body -> motor neurons via the interneurons in the spinal cord goes to particular parts of your skeletal muscles making them move)
parasympathetic divison
calms the body; subdivison of the ANS Two functions: 1. Counterbalancing the activities of the sympathetic nervous system after fight or flight response (calming down). 2. Keeps bodily systems functioning effectively in a state of Homoeostasis (calm state).
Peripheral Nervous System
The division of the nervous system consisting of all of the nerves located outside the central nervous system. -Split up into 2 different divisions: --->Afferent division: -Sends info to the CNS via afferent (sensory) neurons -ex. when you touch something hot with your hand, the info will go to the CNS via afferent neurons to tell your brain that you are touching something hot. --->Efferent division: -Takes info from the CNS to target cells via efferent neurons (to control skeletal muscles, cardiac muscles, and smooth muscles) -ex. after the brain has process that the object you touch is hot and you should remove your hand, it will send signals to the target cells via efferent neurons to move your hand away from the hot object
Central Nervous System
The division of the nervous system consisting of the brain and spinal cord. Function: Interprets sensory info, Initiates motor responses, Center for thoughts & emotions.
Autonomic Nervous System
ls involuntary Controls self-regulated action of internal organs and glands Controls involuntary movements Connects CNS to the bodies internal organs & glands. Visceral muscles control internal organs (self regulating therefore do not need input from the brain). Messages carried between CNS and visceral muscles are designed either to increase ore decrease their activities based on situation.
sympathetic divison
part of the autonomic nervous system responsible for fight or flight system Activates internal muscles, organs and glands to prepare the body for action or to deal with a stressful situation (flight or flight response). Adaptive response increases our changes of survival (Increase heart rate, blood pressure to ensure more oxygen enters our body)