CH16 PT 16 /3
Match each photopigment to the type of retinal cell that produces it.
- Rhodopsin:Rods- Photopsin:Cones- Melanopsin:Ganglion cells
Most human color vision is based upon comparing signals generated by how many types of cones?
3 THREE
Which describes the optic disc?
An area of the retina lacking photoreceptors
What fluid is secreted by the ciliary body?
Aqueous humor
Which fluid is secreted by the ciliary body and fills the anterior cavity of the eye?
Aqueous humor
Which type of retinal cell synapses with the photoreceptors and functions as a first order neuron in the visual pathway?
Bipolar cells
The is a highly vascular, deeply pigmented portion of the vascular tunic located behind the retina.
Choroid
The suspensory ligament attaches the lens to which of the following structures?
Ciliary body
Which structure secretes the aqueous humor?
Ciliary body
Which are the photoreceptors that are primarily responsible for photopic (day) and trichromatic (color) vision?
Cone
Which type of photoreceptor is primarily responsible for photopic (day) vision and trichromatic (color) vision?
Cone cell
Which are types of photoreceptor cells?
Cones Rods
Which describe the choroid?
Contains numerous capillaries Part of the vascular tunic (layer) Highly pigmented
Astigmatism may result from an irregularity in which of the following structures?
Cornea
The anterior chamber of the eye is located between which two structures?
Cornea and iris
Failed convergence of the eyes produces double-vision, also known as which of the following?
Diplopia
The term refers to a relaxed state in which the eyes are focused on far away objects.
Emmetropia
When eyes are focusing on far away objects, they are in which state?
Emmetropia
True or false: As we age, the near point of vision decreases.
False
Which portion of the retina produces the greatest visual acuity (sharpness of image)?
Fovea centralis
Which type of retinal cells function as second-order neurons in the visual pathway, as well as occasionally functioning as photoreceptors?
Ganglion cell
The axons of which retinal cells form the optic nerve?
Ganglion cells
Which term refers to difficulty in viewing nearby objects?
Hyperopia
Which layer of the eyeball includes the retina?
Internal
Which structures are part of the vascular layer of the eyeball?
Iris Ciliary body Choroid
The posterior chamber of the eye is located between which two structures?
Iris and lens
Which are functions of the vitreous body?
Keeps retina smooth Maintains intraocular pressure
The vitreous body, or humor, is a jelly-like substance located between what two structures of the eye?
Lens and retina
Which term refers to a patch of cells in the center of the retina?
Macula lutea
Which type of cone contains a photopsin that is maximally sensitive to wavelengths of light around 531 nm?
Medium-wavelength cones
Which term refers to difficulty in viewing distant objects?
Myopia
What are the two moieties of rhodopsin?
Opsin Retinal
Which area of the retina lacks photoreceptors and is therefore referred to as the "blind spot"?
Optic disc
Rods and cones are examples of which of the following?
Photoreceptor cells
As light passes through different mediums, its path will bend. What is this called?
Refraction
Which structure contains photoreceptors?
Retina
Name the visual pigment present in rods.
Rhodopsin
Which are the photoreceptor cells responsible for night vision?
Rods
Rod cells are primarily responsible for which type of vision?
Scotopic
Which would be true about a person with only one eye?
She would have impaired stereoscopic vision.
The inner layer of the eye contains which of the following?
Start of optic nerve Retina
Having two eyes with overlapping visual fields is necessary for which of the following
Stereoscopic vision
Having two eyes with overlapping visual fields is necessary for which of the following?
Stereoscopic vision
The ligament attaches the lens of the eye to the ciliary body.
Suspensory
What is the function of the lens?
To focus light onto the retina
True or false: Inverted images are focused onto the retina by the lens.
True
True or false: Sensitivity differences during light and dark adaptation result, at least in part, from the difference in bleaching and regeneration rates of photopsin and rhodopsin.
True
True or false: The pigment epithelium of the retina is a darkly pigmented layer that absorbs stray light.
True
The choroid, ciliary body, and iris belong to which of the three tunics of the eye?
Vascular
Which term refers to a molecule that plays a crucial role in visual transduction by changing shape when it absorbs certain wavelengths of light?
Visual pigment
The body is a jelly-like substance located between the lens and the retina of the eyeball.
Vitreous
cells are first-order retinal neurons that synapse with photoreceptors.
biopolar
Which type of retinal cell synapses with the photoreceptors and functions as a first order neuron in the visual pathway?
bipolar
_____ cells are first-order retinal neurons that synapse with photoreceptors.
bipolar
Stereoscopic vision provides for which of the following?
depth
By definition, ___ is double vision resulting from failure of convergence.
diplopia
The visual adjustment that is made when you go from a dark or dimly lit area to a brighter area is called adaptation.
light adaptation
Which term refers to difficulty in viewing distant objects?
myopia
The duct connects the lacrimal apparatus to the nasal cavity.
nasolacrimal
The point of vision refers to the closest an object can be to the eyes and still be focused.
near
The point of vision refers to the closest an object can be to the eyes and still be focused.
near, focal
is the visual pigment present in cones.
photopsin
Rhodopsin is an example of a visual , a molecule that plays a crucial role in visual transduction by changing shape when it absorbs certain wavelengths of light.
pigment
The epithelium of the retina absorbs stray light.
pigmented, pigment, or Pigmented
Which part of the eye forms from a cup-shaped outgrowth of the diencephalon and is actually considered part of the brain?
retina
The choroid is ______.
very vascular