BNNS501 EXAM TWO STUDY GUIDE WITH
COMPLETE SOLUTION
What are some accessory structures of the eye?
Eyebrows
Eyelashes
Eyelids
Conjunctiva
What is conjunctiva?
Thin, protective mucous membrane that lines the inner eye
What is lacrimal fluid?
Tears. Protect the eye cleaning, lubricating and moistening the eyeball. The
fluid contains lysosome which acts as an antibacterial enzyme
What are the 3 cranial nerves relevant to movement of the eye?
Trochlear nerve (IV)
Oculomotor nerve (III)
Abducens (VI)
What are the 4 cranial nerves connected to the eyes?
Trochlear nerve (IV)
Oculomotor nerve (III)
,Abducens nerve (VI)
Optic nerve (II)
What are tunics?
Layers of the eyeball
What are the 3 tunics (layers) of the eyeball?
Fibrous tunic (outer layer)
Vascular tunic (middle layer)
Retina (inner layer)
What is the sclera?
The "white" of the eye, it provides shape and support to the eyeball and is
the site of attachment for extrinsic eye muscles
What is the optic disc?
The site where the optic nerve enters/exits the eye
What structures of the eye are found within the fibrous tunic?
Corna and sclera
What is the cornea of the eye?
Transparent layer covering the iris, it's curved shape helps to focus light onto
the retina (refraction)
What structures of the eye are found within the vascular tunic?
Choroid and ciliary body
,What is the choroid of the eye?
The vascular layer containing blood vessels that provide nutrients to the
retina, it also contains melanocytes which produce melanin that absorb
scattered light
What is the ciliary body of the eye?
It secretes aqueous humour and contains ciliary muscles that alter the shape
of the lens by contracting and relaxing which is essential for focus
(accommodation)
What is aqueous humor?
Clear fluid within the front space of the eye that nourishes the lens and the
cornea
What is the purpose of suspensory ligaments within the eye?
They attach the lens to the ciliary muscles
Define the lens of the eye
It is avascular and located posterior to the pupil and the iris, it fine tunes the
focusing of light rays onto the fovea of the retina for clear vision
What is the iris of the eye?
The coloured portion of the eye, functions by regulating the amount of light
entering the eye
What is the pupil of the eye?
It is a hole in the enter of the iris where light enters the eye
What changes the size of the pupil?
, The contraction and dilation of the iris
Contraction of the iris means the pupil will be ___________________
Smaller
Dilation of the iris means the pupil will be ____________________
Larger
What structures of the eye does the retina contain?
Photoreceptors
Optic disc
Retinal blood supply
Macula lutea
Fovea centralis
What are the 2 types of photoreceptors in the eye?
Rods and cones
What does the retinal blood supply include?
Central retinal artery and central retinal vein
What is the macula lutea of the eye?
Exact centre of the posterior retina
What is the fovea centralisof the eye?
The centre of the macula lutea
Which part of the eye has the highest area of visual acuity?
COMPLETE SOLUTION
What are some accessory structures of the eye?
Eyebrows
Eyelashes
Eyelids
Conjunctiva
What is conjunctiva?
Thin, protective mucous membrane that lines the inner eye
What is lacrimal fluid?
Tears. Protect the eye cleaning, lubricating and moistening the eyeball. The
fluid contains lysosome which acts as an antibacterial enzyme
What are the 3 cranial nerves relevant to movement of the eye?
Trochlear nerve (IV)
Oculomotor nerve (III)
Abducens (VI)
What are the 4 cranial nerves connected to the eyes?
Trochlear nerve (IV)
Oculomotor nerve (III)
,Abducens nerve (VI)
Optic nerve (II)
What are tunics?
Layers of the eyeball
What are the 3 tunics (layers) of the eyeball?
Fibrous tunic (outer layer)
Vascular tunic (middle layer)
Retina (inner layer)
What is the sclera?
The "white" of the eye, it provides shape and support to the eyeball and is
the site of attachment for extrinsic eye muscles
What is the optic disc?
The site where the optic nerve enters/exits the eye
What structures of the eye are found within the fibrous tunic?
Corna and sclera
What is the cornea of the eye?
Transparent layer covering the iris, it's curved shape helps to focus light onto
the retina (refraction)
What structures of the eye are found within the vascular tunic?
Choroid and ciliary body
,What is the choroid of the eye?
The vascular layer containing blood vessels that provide nutrients to the
retina, it also contains melanocytes which produce melanin that absorb
scattered light
What is the ciliary body of the eye?
It secretes aqueous humour and contains ciliary muscles that alter the shape
of the lens by contracting and relaxing which is essential for focus
(accommodation)
What is aqueous humor?
Clear fluid within the front space of the eye that nourishes the lens and the
cornea
What is the purpose of suspensory ligaments within the eye?
They attach the lens to the ciliary muscles
Define the lens of the eye
It is avascular and located posterior to the pupil and the iris, it fine tunes the
focusing of light rays onto the fovea of the retina for clear vision
What is the iris of the eye?
The coloured portion of the eye, functions by regulating the amount of light
entering the eye
What is the pupil of the eye?
It is a hole in the enter of the iris where light enters the eye
What changes the size of the pupil?
, The contraction and dilation of the iris
Contraction of the iris means the pupil will be ___________________
Smaller
Dilation of the iris means the pupil will be ____________________
Larger
What structures of the eye does the retina contain?
Photoreceptors
Optic disc
Retinal blood supply
Macula lutea
Fovea centralis
What are the 2 types of photoreceptors in the eye?
Rods and cones
What does the retinal blood supply include?
Central retinal artery and central retinal vein
What is the macula lutea of the eye?
Exact centre of the posterior retina
What is the fovea centralisof the eye?
The centre of the macula lutea
Which part of the eye has the highest area of visual acuity?
