| where is and what is the function of the lacrimal gland (accessory organs) | located in the upper margin of both eyes and it is where tears come out of |
| lacrimal ducts where is it located and what is the function (accessory organs) | To drain tears on to the conjunctiva to be drained in to the lacrimal canal and sacs and it is located beside the lacrimal gland upper region of the eye |
| function of the lacrimal canals sacs and ducts (accessory organs) and what is the Puncta | lacrimal canals and sacs take the tears from the ducts but cant drain all and hence why tears are visible
puncta is the opening of the lacrimal glands |
| what is the iris | iris is the coloured part of the eye |
| ciliary muscles function | controls the shape of the lens |
| what does intrinsic mean | muscles inside the eye |
| what are the extrinsic muscles of the eye | superior rectus , inferior rectus , medial rectus and lateral rectus
Superior and inferior oblique muscles. upper and under the eye |
| what is in the fibrous layer of the eye ( what is visible to us) | cornea, sclera, |
| what is the cornea | cornea is the clear bubble on top of the iris |
| sclera | sclera is the white around the eye |
| function of the choroid (part of the middle layer of the eye) | to provide nutrients and O2 to the sclera and retina |
| function of the ciliary body and location | produces some of the eye fluids and adjusts the shape of lens to focus the image to the retina. located in the anterior region of the eye |
| function of the iris and location | controls the amount of light entering the eye. located in front of the ciliary body |
| function of the retina | the retina is responsible for capturing light and sent to the rods and cones and a impulse is sent to the bipolar cells and a the ganglion neurons collects the information from the rods and cones |
| where is the retina located | located superior region of the eye in the inner layer (posterior cavity) |
| cavities of the eye | anterior and posterior cavity |
| where is the anterior cavity located | Is located in front of the lens, & can be further divided into anterior & posterior chambers |
| where is the posterior cavity located | Located within the entire space posterior to the lens, ligaments, & ciliary body |
| Humors in the eye | aqueous and vitreous humors |
| function of the aqueous humor and where is it located | A clear, watery fluid
flows through the eye located in the visible part of the eye
creates an ‘intraocular pressure’ to inflate the eyeball & help retain its shape. |
| vitreous humor function | helps prevent the eyeball from collapsing, stabilises & keeps the eyeball inflated (intraocular pressure), supporting the retina |
| what is the fovea centralis function | when light hits the fovea centralis it is then changed into a electrical impulse sends it to the brain. - responisble for sharp central vision like reading |
| how we see | The pathway between the photoreceptors & the brain, is called the Visual Pathway
So, for us to see an image, that image needs to be sent to the retina
The retina stimulates the rods/cones, basal, ganglion neurons
Once these neurons are stimulated, they forward the image onward via the cranial nerve II
Onward to the cerebral cortex for interpretation |
| intepretation of the image to the brain | As the image enters the eye, sensory nerve fibres carry it onward to the brain for interpretation
Information coming from the left visual field is transmitted to the right cerebral hemisphere
Two sets of fibres are received by the retina, the temporal & nasal fibres
The temporal fibres continues on its pathway, the nasal fibres cross at the optic chiasma
So the right nasal fibres are received on the left side of the brain & the left nasal fibres are received on the right side of the brain
The image travels onward to the visual cortex |
| optic axis | array of transmitted light |
| conjunctiva function (accessory organs of the eye) | the mucous membrane that lines the eyelids |
| what are the intrinsic muscles of the eye | iris and ciliary |
| regions of the ear | outer ear, middle ear and inner ear |
| group of small bones in the ear | ossicles |
| names of the small bones in the ear | malleus, incus and stapes located in the middle ear |
| function of the ossicles | arranged in a away to transmit sound vibrations
function is to send sound waves to the inner ear |
| tympanic membrane function | after the outer ear has collected sound it hits the tympanic membrane which vibrates sending the vibrations to the ossicles |
| another term for earwax | cerumen |
| where is earwax produced | ceruminous glands |
| swimmers ear medical term | otitis media, occurs in the midde due to water coming in |
| where does the eustachian tube lead to | the eustachian tube connects the middle ear and the pharynx |
| function of the eustachian tube | the function of the eustachian tube is to equalise the pressure in the middle ear to the atmosphere |
| what happens when there is unequal pressure in the ear and the atmosphere | unequal pressure can block hearing |
| difference between an adults eustachian tube and a childs | the difference is that a child's eustachian tube is more horizontal and shorter making it easier for pathogens to travel to the middle ear, where as in adults the eustachian tube is more vertical and longer. |
| the function of the vestibules? | the function of the vestibules are informing the body the postion of the head wheter you are upside down or up right, |
| the function of the semicircular canals? | semilunar canals are three small tubes filled with fluid which helps you keep your balance |
| function of the ganglion nuerons in the eye | to collect the information that the rods and cones have collected |
| function of the rods and cones | rods collect black and white information and the cones collect couloured information |
| location of the rods and cones | found in the retina |
| cavities in the eye | anterior, and posterior |
| location of the anterior cavity of the eye | anterior is in front of the lens and full of aqueos humour |
| humours in the eye | aqueos and vitreous |
| what is and where the is the aqueous humour located in the eye | found in both posterior and anterior chambers of the eye, it is a clear watery fluid secreted by the capiliary blood where it is stored as it flows through the eye
this helps keeps the eyes shape and retain its shape, needs to remain constant if the pressure changes then it could lead to blindness |
| what is and where is the vitreous humour located in the eye | found in the posterior region of the eye which is 99% water and 1% collagen fibre
contributes to intraocular pressure and helps prevent eyeball from collapsing there keeping it inflated which supports the retina |
| location of the posterior cavity in the eye | posterior cavity is the entire space behind the lens |
| external accessory structures of the eye | eye lashes, eye brows, eye lids, canthus, conjunctiva |
| vascular layer in the eye | vascular layer of the eye contains the choroid, ciliary body, and iris. |
| function of the choroid | the function of the choroid is it provides the retina and sclera with o2 and nutrients
Melanin gives it a dark brown colour, this colour is to reduce glare & reflection back |
| function of the ciliary body | produces humours and adjusts the shape of the lens |
| landmarks when doing a otoscopy examination on the ear | you can see the tympanic membrane and the cone of light, you can also see the malleus and incus
the colour of the ear canal is also a pearly grey colour |
| assessments of the ear | otoscopy examination, whispered voice test and finger rubbing test |
| how is the whispered voice test used | Stand in front or side of the client. Ask them to cover one ear, shield your mouth to avoid lip reading, say simple words in soft whisper, eg ball chair cat
Repeat with other ear |
| how is the finger rubbing test used | Hold a hand a few cm’s from the client ear and rub fingers together repeatedly with the other ear. |
| what is the function of the nasolacrimal duct in the eye | it connects the lacrimal ducts to the inferior meatus of the nose |
