Nervous System, Includes Eye Flashcards
what does the CNS consist of
brain and spinal chord
what does the PNS consist of
sensory and motor neurons
steps in responding to a stimulus
1.receptors detect a stimulus
2.the impulse is sent along the sensory neuron to the spinal chord
3.the CNS integrates the information and, if necessary, sends it to the brain for processing prior to initiating a response
4.the impulse is sent from the CNS along the motor neurons to the effector
5.the effector generates the response
what do sensory neurons do in the PNS
they conduct impulses from sensory receptors in the skin and other locations
what do motor neurons do in the PNS
they cause muscles to contract, and other organs to function. They transmit impulses from the CNS to the muscles and other organs
what do the interneurons do in the CNS
transmit impulses between sensory and motor neurons within the brain or spinal chord
what do chemoreceptors do
detect the presence of chemicals
what do thermoreceptors do
detect changes in the temperature
what do mechanoreceptors do
detect mechanical changes in the environment
what do photoreceptors do
detect the presence of light
auditory receptors (mechanoreceptors)
hair cells in the inner ear vibrate according to the pitch and volume of sounds. they send impulses via the auditory nerve to the brain for processing
gustatory receptors (chemoreceptors)
the tongues of many animals are covered with papillae which contain taste buds.
visual receptors (photoreceptors)
photoreceptors in the retinal layer of the eye respond to light
somatosensory (mechanoreceptors)
skin contains a variety of receptors which respond to temperature, touch or pressure
olfactory(chemoreceptors)
receptors in the nasal cavity respond to odour molecules in the air
description of the eyelid
fold of skin which covers the eye
function of the eyelid
cleaning and protecting the eye
description of the cornea
transparent covering on the eye