Nervous System Unit Final Flashcards
what type of pigment is in cones and what is it composed of
photopsin which is composed of opsin and retinal
what are the projections on the hair cells called
stereocilia
what does the lens do
focuses the light rays that enter through the pupil onto the retina
how do the semicircular canals work
there is a bulge at the base of each canal that contains stereocilia of the hair cells stuck in a jelly-like covering called a cupula. when the head rotates fluid inside the canal moves and bends the stereocilia which causes the hair cells to send rotational information to the brain
what happens to the basilar membrane when your ears perceive loud noises
the louder the noise, the more pressure that is put on the basilar membrane
what protects the brain
the skull and meninges
what are the two divisions of the motor pathways
somatic nervous system and autonomic nervous system
examples of chemoreceptors receptors (4)
taste buds on the tongue, olfactory receptors in the nose, osmoreceptors in the hypothalamus, receptors in the carotid artery and aorta
is the external surface of the tympanum concave or convex
concave
whats the fovea centralis
small area located at the back of the eye in the centre of the retina that contains a high density of cones
what does the lateral ventricle do
produce and store cerebrospinal fluid
what does the sclera do (3)
it protects the eye, maintains the eyes shape and serves as a key attachement point for different muscles
true or false: if something has a sympathetic system it also has a parasympathetic nervous system
true, both systems are always present
is the somatic nervous system voluntary or involuntary
voluntary
difference between the functions of the fovea and the macula
the fovea provides sharp acute vision where as the macula provides sharp central vision
whats the pupil
the black opening in the middle of the iris
what is the function of the pinna
to collect sound waves, enhance their vibration and focus them into the auditory canal
what causes myopia
when the eye is elongates so the focusses light falls in front of the retina instead of on the photoreceptors
whats the optic disk
small round area at the back of the eye where the retina and optic nerve connect that does not contain any photoreceptors
what does the blood-brain barrier do
protects the brain and supplies the brain with nutrients and oxygen
what are the main structures of the hindbrain
pons, cerebellum and the medulla oblongata
what is gravitational equilibrium
the balance required when moving forward and backward
what is sulcus
the groves in between the gyri on the surface of the brain
whats hyperopia
when they can clearly see objects that are far away but cannot clearly focus on objects close up