Special senses knowledge check

What structure regulates the amount of light passing to the visual receptors of the eye?

iris

Lack of one or more _____ pigments can result in color blindness. 

cone

Please match the following: 

A

B

A

B

A

Strabismus is a congenital weakness of the external eye muscles.

True

Glaucoma is the clouding of the lens which prevents light to pass through efficiently

False

Nerve fibers from the medial aspect of each eye ________.

cross over to the opposite side at the chiasma

Overlap in the visual fields of our eyes ________.

allows us to subconsciously estimate the distance of objects based on the different angles the image strikes our two retinas

Parasympathetic innervation of the sphincter puppillae muscle would cause ____________. 

the pupil to contract (decrease in size)

Humans can see several thousand shades of color but have cone photoreceptors that are sensitive to only three (perhaps four) wavelengths of light. What is the best explanation for why we see so many colors?

Color perception is achieved by the activation of various combinations between the three cone types.

Nerve fibers from the medial aspect of each eye ________.

cross over to the opposite side at the chiasma

Which of the following is the best explanation for our perception of color?

Cones come in three types, each sensitive to different wavelengths of light.

As light travels through the eye, it passes through several structures or chambers before reaching the retina. Which list below gives those structures in the correct order?

cornea, anterior chamber, pupil, lens, posterior segment

The sclera is a transparent region of the eye that allows light to pass through. 

False

Overlap in the visual fields of our eyes ________.

allows us to subconsciously estimate the distance of objects based on the different angles the image strikes our two retinas

The elasticity of the lens decreases with age. Leading to which of the following?

less accommodation of the lenses and difficulty focusing on nearby objects

What is the main function of the rods in the eye?

vision in dim light

Which of the following is the best explanation for our perception of color?

Cones come in three types, each sensitive to different wavelengths of light.

Bitter taste is elicited by ________.

alkaloids

Which of the following taste sensations is incorrectly matched to the chemicals that produce it?

umami-triglycerides and fatty acids

Which of the following types of neurons are replaced throughout adult life?

olfactory receptor cells

Sour taste receptors are stimulated by hydrogen ions of acidic food substances.

True

Odorants must be volatile to be smelled

True

Seventy percent of all sensory receptors are located in the ________.

eye