Ch 12: Sense Organs Flashcards
What are the 6 senses?
Sight, hearing, taste, touch, balance, smell
What are chemoreceptors, photoreceptors and mechanoreceptors?
Chemoreceptors = sensory stimulus
Photo = light stimulus
Mechanoreceptors = mechanical stimulus
What are proprioreceptors and exteroreceptors?
Proprio = in skeletal system, joints, bones; detect body position.
Exteroreceptors: on surface of body
Where is image sent from eye processed (which lobe of brain)?
Occipital
Which kind of humor does posterior vs anterior eye contain?
Anterior : aqueous
Posterior : vitreous
What are the 3 covers of the wall of the eye?
External: has cornea and sclera
Medium: has choroid and iris
Internal: has retina
How many rod vs cone cells are found?
Rod = 120 million
Cone = 6-7 million
For rhodopsin, half the pigment is derived from the protein opsin, what is the other half derived from?
Vitamin A.
Why is the optic disc a blind spot?
Cz it is devoid of nerves.
Describe the light path in the eye.
Cornea, pupil (changes shape) crosses aqueous humor, lens (focuses image on retina), vitrous humor.
How is the lens shape when looking at far vs near object?
Far: flat
Near: convex disc
What is strabismus
It is the crossing of the eyes/ not focusing
What is myopia, how is it solved?
It is when the image forms in front of the lens, a biconcave lens helps.
What is hypermetropie? How is it solved?
It is when image is formed behind lens, biconvex lens.
What is astigmatism? How is it solved?
It is when the image isn’t focused and a person cant distinguish between 2 close points, solved by a special lens called a TORICE LENS.
What is dyschromatopsia, what’s it caused by?
It is color blindness, caused by the absence of certain cone cells that react to certain colors.
Which lobe of the brain receives hearing impulses?
Temporal lobe.
Name the parts of the internal, middle and external ear.
External: external auditory canal, timpan, ear pavilion
Middle: 3 oscioare, ciocan (malleus), nicovala (incus), scăriță (stapes), fereastra ovala, eustachian tube.
Inner: Cohlea, perilymph.
Describe the basic auditory path throughout the ear.
- external auditory canal
- timpan
- the 3 ossicles
- fereastra ovala
- perilymph that changes
- organ of corti in Cohlea
- dendrites of neurons whose axons make up the Vestibulocohlear nerve
- contact with hair cells
- tectorial mb sets hair cells in motion
- Nerve impulse
- Fereastra rotunda bulges
- Decreases pressure
13 . Cohlear branch - Vestibulocohlear nerve
- Temporal lobe
What types of receptors are taste buds?
They are chemoreceptors and exteroreceptors.
What are the 5 primary tastes? And where are they most felt on tongue?
Dulce- on tip
Acru(sour)- anterior lateral portion
Amar (bitter)- back of the tongue.
Sărat: posterior lateral/tip
Umami: in pharynx, due to glutamate.
Describe the steps taken to taste.
Molecules enter taste pore (por gustativ), nerve impulse happens along glosofaringial + facial nerves, brain (thalamus), parietal lobe (taste stimulus)
Which lobe is responsible for taste?
Parietal lobe.
What type of cells are olfactory cells?
They are chemoreceptors and exteroreceptors.
Describe the route to smelling.
Smell substance, molecules enter nose, stimulate olfactory cells by touching their cilia (upper nasal cavity), olfactory nerve, to brain through LAMA CIRCUITA A OSULUI ETMOID, olfactory bulbs, olfactory tract, FRONTAL + TEMPORAL LOBES OF OLFACTORY CORTEX.
What lobes are with interpreting smell?
Frontal + temporal.
What types of cells are involved in balance?
Ciliated cells in ampulla and macula, they are prorioreceptors and mechanoreceptors.
Explain dynamic equilibrium.
Change position of head = endolymph in semicircular canals act on hair cells = stimulation = nerve impulse = vestibular branch = vestibulo cohlear nerve = brain muscles = adjust position
Explain maintaining posture/ static equilibrium
In utricle and sacula theres calcium carbonate (caliculi) = move position of head =pressure = caniculi change positions = act on ciliated cells = nerve impulse via Vestibulocohlear nerve = brain = motor impulse to muscles
