Nervous & Endocrine Systems

nervous system

complex system of organs that controls the body through electrical impulses and neurotransmitters; functions very quickly

central nervous system

organ system that includes the brain, brainstem, and spinal cord; protected by skeletal structures

spinal cord

“highway” between the brain and the rest of the body; controls some things independently of the brain (e.g. reflexes)

blood brain barrier

a semi-permeable membrane that filters out harmful substances before they can reach the brain

peripheral nervous system

controls all movement throughout the body; connection between the spinal cord and the rest of the body

autonomic nervous system

part of the peripheral nervous system; controls involuntary actions (e.g. heartbeat, breathing, digestion)

sympathetic nervous system

part of the autonomic nervous system; initiates “fight or flight” responses (e.g. increased heart rate, dialated pupils)

parasympathic nervous system

part of the autonomic nervous system; returns the body to a normal state after a period of excitement (e.g. slows heart rate, lowers blood pressure)

somatic nervous system

part of the peripheral nervous system; controls voluntary actions, including unconscious habits (e.g. walking, talking)

endocrine system

a system of organs and glands that control the body by releasing hormones into the bloodstream; functions more slowly

pituitary gland

the “Master Gland” that controls the release of hormones from other glands; located at the base of hypothalamus