19 terms

science chapter 18

nervous system
the part of an organism that gathers,processes,and responds to information.
a change in an organism's enviorment that causes a response.
the basic functioning unit of the nervous system:a nerve cell.
the gap between two neutrons.
central nervous system
system made up of the brain and the spinal cord.
the part of the brain that controls the memory,language,and thought.
the part of the brain that controls voluntary muscle movement and regulkates balance and posture.
brain stem
the area of the brain that controls involuntary functions.
spinal cord
a tube like structure of neurons that sends signals to and from the brain
peripheral nervous system
system made of sensory and motor neurons that transmit information between the central nervous system and the rest of the body.
an automatic movement in response to a stimulus.
sensory system
the part of your nervous system that detects or senses the enviorment.
special structures in all parts of the sensory system that detects stimuli.
an area at the back of the eye that includes two types of cells-rod cells and cone cells-that contain photoreceptors.
a thin membrane between the outer ear and the inner ear.
endocrine system
system consisting groups of organs and tissues that release chemical messages into the blood stream.
a chemical signal that is produced by an endocrine gland in one part of an organism and carried in the bloodstream to another part of the organism.
negative feedback
a control system in which the effect of a hormone inhibits further release of the hormone: sends signal to stop a response.
positive feedback
a control system in which the effect of a hormone causes more of the hormoneto be released:sends a signal to increase a reponse.