chapter 38 Flashcards
nerve net
interconnected nerve cells found in cnidarians
nerves
axons of multiple nerve cells are often bundled together to form these
ganglia
nerve cell clusters or a group of nerve cell bodies to provide intermediary connections
CNS central nervous system
brain and nerve cords
PNS peripheral nervous system
composed of nerves and ganglia
reflexes
the body’s automatic responses to certain stimuli
gray matter
consists of mainly neuron cell bodies with glia
white matter
bundles of myelinated axons
afferent neurons
transmit information to CNS
efferent neurons
transmit information away from CNS
motor system
carries signals to skeletal muscles and can be voluntary or involuntary
autonomic nervous system
regulates smooth and cardiac muscles and is generally involuntary
sympathetic division
regulates the flight or fight response
parasympathetic division
generates opposite responses in target organs and promotes claiming and a return to reset and digest functions
enteric division
controls activity of teh digestive tract pancreas and gallbladder
sensory reception
detection of stimuli by sensory receptors
sensory receptors
detect stimuli, interact directly with stimuli both inside and outside the body
sensory transduction
the conversion of stimulus energy into a change in the membrane potential of a sensory receptor
sensory transmission
occurs as nerve impulses or action potentials are conveyed
perception
the brains contraction of stimuli
mechanoreceptors
sense physical deformation caused by stimuli such as pressure, touch, stretch, motion, and sound
electromagnetic receptors
detect electromagnetic energy such as light, electricity and magnetism
thermoreceptors
detect heat and cold
pain receptors
detect stimuli that reflect conditions that could damage animal tissues
