Chapter 6 The Visual System Flashcards
Light can be thought of in two ways:
- Particles of energy (photons) 2. Waves of energy (electromagnetic radiation)
How is light defined?
Waves of electromagnetic energy between 380 and 760 nanometers in length
Why are wavelength and intensity two properties of light that are of interest?
Wavelength plays an important role in the perception of colour and intensity in the perception of brightness
Vision is based on what range of visible light?
380-760 nm
What is the smallest possible unit of light energy?
photon
The amount of light hitting the retinas is regulated by what?
The Irises: “donut-shaped” bands of contractile tissue (give eye colour)
Light enters the eye through?
The pupil: hole in the iris
The adjustment of pupil size in response to changes in illumination represents a compromise between what two concepts?
Sensitivity and Acuity
What is sensitivity?
ability to detect the presence of dimly lit objects
What is acuity?
Ability to see details of objects
Label A-F
A- Cornea
B- Iris
C- Pupil
D- Ciliary Muscles
E- Optic Nerve
F- Sclera
Where is the lens and what does it do?
Behind the pupil
-focuses incoming light on the retina
Define accomodation. How is it achieved?
the process of adjusting the configuration of the lenses to bring images into focus on the retina.
-Requires Ciliary muscles
What is binocular disparity?
Difference in position of the same image on the two retinas
What is the path of light in the eye?
Cornea -> Pupil -> lens -> retina -> optic nerve
Label A-C (the cell layers)
Label D-J
A. Photoreceptor Layer
B. Bipolar Cell layer
C. Ganglion Cell layer
D. Photoreceptors
E. Bipolar Cell
F. Ganglion cell
G. Cone
H. Rod
I. Horizontal Cell
J. Amacrine Cell
