UNIT 4 CONT...

• Nervous system 
• central nervous system: the brain and spinal cord 
• peripheral nervous system: all nerves that are not encased in bone. everything but the brain and spinal cord
• SOMATIC: controls voluntary muscle movement. Uses motor neurons.
• autonomic: controls the automatic functions of the body 
• Sympathetic:fight or flight response. Automatically accelerates heart rate, breathing, dilates pupils, slows down digestion. 
• parasympathetic: automatically slows the body down after a stressful event. Heart rate and breathing slow down pupils constrict and digestion speeds up.
• reflexes: normally, sensory neurons take info up through spine to the brain, some reactions occur when sensory neurons reach just the spinal cord.
• hormones