Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
91 Cards in this Set
- Front
- Back
|
What are the two types of receptors? |
A specialized ending of a sensory neuron Or A separate cell that is closely associated with a sensory neuron |
|
|
Term: sensory adaptation |
This is when the receptor eventually stops sending a signal even though the stimulus is still present |
|
|
Receptors that show sensory adaptation are referred to as this: |
Phasic receptors |
|
|
Receptors that do not show sensory adaptation are referred to as: |
Tonic receptors |
|
|
Where are taste buds found? |
Along the sides of papillae on the top of the tongue |
|
|
How many tastebuds are in a human mouth? |
10,000 |
|
|
What is a taste pore? |
The opening of the taste bud |
|
|
Term: gustation |
The mechanism of taste |
|
|
Four facts about olfactory mucosa |
Roughly 3cm square Contains about 6million olfactory receptors About a thousand different types of receptors We can detect about 10,000 different smells |
|
|
From the outside to the fovea, what are the layers of the eye (what we see through) |
Cornea, aqueous humor, lens, vitreous humor, fovea |
|
|
Where is the aqueous humor produced? |
Ciliary body |
|
|
Where does the aqueous humor circulate through? |
Anterior (front) chamber of the eye. Between the cornea and lens |
|
|
What does the aqueous humor do? |
Carries nutrients to the cells of the cornea and lens |
|
|
Term: iris |
Pigmented ring of smooth muscle, controls the size of the pupil opening. |
|
|
The types of muscle of the iris and what they do and what controls them |
Constrictor (circular) muscle: contraction results in smaller pupil. Parasympathetic control Dialator (radial) muscle: contraction results in increase in pupil size. Sympathetic control |
|
|
Three main layers of an eye |
Sclera Choroid Retina |
|
|
How are the ciliary muscles connected to the lens? |
With suspensory ligaments |
|
|
Term: visual acuity |
The ability to see detail |
|
|
Term: fovea |
A depression in the retina packed with cones only. Most light is focused here and allows visual acuity. Overlying cells are pulled apart. |
|
|
Term: macula lutea |
Area around the fovea containing only cones. Overlying cells get in the way of visual acuity |
|
|
What shape is the lens? |
Biconvex |
|
|
What are the two types of photoreceptors? |
Rods: low intensity light Cones: high intensity light, and respond to color |
|
|
What is the blind spot called? |
Optic disc |
|
|
Why does light bend? |
Passage of light through different densities, and any angle other than 90° |
|
|
What does the degree of refraction (bending of light ray) depend on? |
The difference in density of two substances The angle at which the ray enters. Greater density difference and angle means more bending |
|
|
What part of the eye bends light the most? |
Cornea due to density difference between air and solid |
|
|
What happens when focusing on a near object? |
Ciliary muscles contract, which loosens the ligaments. Lens takes on a rounder/stronger shape Iris constricts This is under parasympathetic control |
|
|
What happens when focusing on a far object? |
Ciliary muscles relax, which increases tension on ligaments This makes the lens thinner The iris dialates under sympathetic control |
|
|
What does perception of color depend on? |
The ratio of stimulation of the 3 cone types |
|
|
What are the three cone types? |
Red, green, and blue |
|
|
How many cones are found in a retina? |
About 6 million |
|
|
Why can't you see color with rods? |
Rhodopsin; it absorbs all visible wavelengths of light and does not discriminate and therefore does not detect color |
|
|
How many rods are in a retina? |
125 million |
|
|
What are the two photopigment molecules found in rods and cones? |
Opsin- a protein Retinene- a derivative of vitamin A (this is the light absorbing part) |
|
|
What is normal vision called? |
Emmetropia |
|
|
Term: hyperopia |
Far sightedness Eyeball is too short and/or the lens is too weak Near light is focused behind the retina Correction is convex lens |
|
|
Term: myopia |
Near sightedness Eyeball is too long and/or lens is too strong Distant light is focused in front of retina Correction is concave lens |
|
|
Term: astigmatism |
The curvature of the cornea is uneven |
|
|
Term: cataracts |
Lens becomes cloudy from proteins breaking down |
|
|
Term: Glaucoma |
Increase in build up of aqueous humor. Ducts that normally drain fluid are blocked and the build up pushes back causing loss of blood flow which can lead to blindness |
|
|
Term: presbyopia |
Age related reduction in the lens' ability to accommodate due to loss of elasticity Treatment is bifocals, progressive lenses, or reading glasses |
|
|
What are the ducts called where aqueous humor drains? |
Canal of shlemm |
|
|
The three parts of the ear |
Outer, middle, inner |
|
|
What is the purpose of the pinna? |
Direct sound to auditory canal |
|
|
Two purposes of the auditory canal: |
Directs sound to eardrum(tympanum) and produces ear wax |
|
|
The three main parts of the middle ear: |
Tympanum, ossicles, eustachian tube (also oval window) |
|
|
Three bones of the ossicles |
Malleus, incus, stapes |
|
|
The main purpose(s) of the eustachian tube |
Allows for even pressure on either side of the tympanum Helps maintain hearing sensitivity |
|
|
What do photoreceptors respond to? |
Light energy |
|
|
What do chemoreceptors respond to? |
Chemicals in food or odors, as well as H2O and CO2 levels in blood |
|
|
What do mechanoreceptors respond to? |
Pressure and movement |
|
|
What do thermoreceptors respond to? |
Change in thermal energy |
|
|
What are the four types of body receptors? |
Chemoreceptors Mechanoreceptors Photoreceptors Thermoreceptors |
|
|
For a substance to be smelled, it needs these two properties: |
To be volatile and water soluble |
|
|
For a substance to be smelled, it needs these two properties: |
To be volatile and water soluble |
|
|
What layer of the eye is the iris found in? |
Choroid layer |
|
|
How does an eyeball stay round and firm? |
It is filled with vitreous humor |
|
|
How does an eyeball stay round and firm? |
It is filled with vitreous humor |
|
|
What layer of the eye are photoreceptors found? |
Retina |
|
|
Which occipital lobe receives which signals |
Right receives right visual from each eye, and left receives left visual from each eye |
|
|
What is the purpose of the optic chiasm? |
It allows signals from the eyes cross to the proper occipital lobe |
|
|
These muscles control the shape of the lens: |
Ciliary muscles |
|
|
These muscles control the shape of the lens: |
Ciliary muscles |
|
|
Why does the iris constrict when focusing on close objects? |
To focus light onto the fovea |
|
|
What are the two photopigment molecules in cones and rods? |
Opsin- a protein Retinene-the light absorbing part, a derivative of vitamin A |
|
|
Rods contain a third photo pigment; |
Rhodopsin - absorbs all visible wavelengths of light |
|
|
Rods contain a third photo pigment; |
Rhodopsin - absorbs all visible wavelengths of light |
|
|
What is color blindness caused by? |
Lacking a particular cone type |
|
|
What is color blindness caused by? |
Lacking a particular cone type |
|
|
What are the parts of the outer ear? |
Pinna and auditory canal |
|
|
What are the parts of the middle ear? |
Tympanum, ossicles, oval window, and eustachian tube |
|
|
What are the parts of the inner ear? |
Vestibule - composed of utricle and saccule, maintain gravitational equalibrium Semi-circular canals - maintain rotational equalibrium Cochlea - "snail shell" that contains sensory receptors |
|
|
This is the hearing apparatus in the cochlea |
Organ of Corti |
|
|
How is pitch or tone determined? |
By the frequency of vibrations, which determines what part of the organ of corti sends the signal |
|
|
How is the intensity or volume of sound determined? |
By the amplitude of sound waves |
|
|
How is the quality of sound determined? |
Depends on the sounds overtones |
|
|
How does your ear try to protect itself from too loud sounds? |
The muscles connected to the malleus and stapes contract, limiting their movement |
|
|
What are the two types of deafness? |
Conductive deafness and sensorineural deafness |
|
|
Term: conductive deafness (and cause) |
Sound waves do not reach the fluids of the inner ear. Can be caused by a blockage |
|
|
Term: sensorineural deafness |
Sound waves are not translated into nerve signals that are interpreted by the brain as sound |
|
|
What is the organ of corti composed of? |
Basilar membrane Stereocilia Techtorial membrane |
|
|
What makes up the saccule and utricle? |
Otoliths in gel on top of stereocilia, embedded in sensory cells |
|
|
What makes up the ampulla? |
Cupula (the gel) surrounds the stereocilia and sensory cells |
|
|
What part of the organ of corti does not move? |
Techtorial membrane |
|
|
What main nerve leaves the ear and what smaller nerves does it consist of? |
Vestibulo-cochlear nerve Consists of vestibular nerve (carries signals from the vestibule and semi circular canals) Auditory (cochlear) nerve, carries signals from organ of corti |
|
|
What are possible causes of conductive deafness? |
Ear canal blockage Ruptured tympanum Damaged ossicles Middle ear infection |
|
|
What are possible causes of sensorineural deafness? |
Damaged stereocilia in organ of corti Nerve damage between cochlea and brain Brain damage |
|
|
Where are ampulla found? |
In the semi circular canals |
|
|
What are otoliths made of? |
Calcium carbonate |
|
|
What are the three layers of the retina? |
Photoreceptors Bipolar cells Cells from optic nerve |
|
|
What is the connection between the middle ear and vestibule? |
Oval window |
