Deck 6: Vision

Question 1

Sarah is in charge of lighting for a school play,and she must find the right "gel," or color filter,to produce a light with a wavelength of about 680 nm.When used on stage,the light will look

A) violet.
B) green.
C) yellow.
D) red.

Answer 1

violet.

Question 2

Large amplitude waves of light are interpreted as

A) dim.
B) bright.
C) saturated.
D) pale.

Answer 2

bright.

Question 3

Which of the following has been proposed as a possible advantage for primate color vision?

A) the ability to detect camouflaged prey
B) improved detection of depth
C) the ability to track large numbers of objects
D) improved detection of large,moving shadows

Answer 3

improved detection of depth

Question 4

Electromagnetic radiation:

A) does not really exist.
B) can be described as the movement of tiny particles called photons.
C) is made up of tiny particles called electromagnetons.
D) describes only the type of energy that is visible to the human eye.

Question 5

Longer wavelengths,such as microwaves,would not make a good basis for a visual system because

A) most longer wavelengths are blocked by the earth's atmosphere.
B) they travel at too slow a speed.
C) they are too abundant at the earth's surface to be useful in vision.
D) long wavelengths penetrate objects instead of being reflected from them.

Question 6

Ultraviolet light would not make a good basis for a visual system because

A) it passes through objects rather than reflecting from them.
B) it is too abundant at the surface of the earth.
C) most ultraviolet light is blocked by the earth's atmosphere.
D) it travels at too slow a speed.

Question 7

Based on the placement of the human eye,we should probably be classified as:

A) primarily a prey species.
B) primarily a predator species.
C) both a prey and a predator species.
D) neither a prey nor a predator species.

Question 8

The range of electromagnetic energy visible to humans falls between _________ nm.

A) 400 and 700
B) 100 and 600
C) 700 and 1,000
D) 1000 and 10,000

Question 9

Within the visible light spectrum,shorter wavelengths are perceived as_________,whereas longer wavelengths are perceived as _________.

A) red;violet
B) violet;red
C) yellow;blue
D) red;green

Question 10

Tears shed in response to emotional events _________ tears shed while peeling onions.

A) contain more protein than
B) contain more glucose than
C) contain less water than
D) have the same composition as

Question 11

The amplitude of a light wave is encoded as _____________,while the wavelength of a light wave is encoded as ___________________.

A) brightness;color
B) color;brightness
C) saturation;reflection
D) hue;saturation

Question 12

Among the advantages of light as a stimulus is the fact that light

A) passes through most objects.
B) is absorbed by the ozone layer of the atmosphere.
C) does not travel in straight lines.
D) travels very quickly.

Question 13

The double pupils in each eye of Anableps anableps allows the fish to overcome distortions of light in both water and air caused by

A) refraction.
B) reflection.
C) absorption.
D) both reflection and absorption.

Question 14

Christopher and his friends are watching a football game.Which of the following features of the visual system should be especially helpful to these fans as they try to keep track of the movements of their team's players?

A) Scotopic vision
B) Retinal disparity
C) Trichromacy
D) Color constancy

Question 15

A sweater looks blue because it has properties that

A) reflect short wavelengths while absorbing longer wavelengths.
B) reflect long wavelengths while absorbing shorter wavelengths.
C) refract short wavelengths while absorbing longer wavelengths.
D) refract long wavelengths while absorbing shorter wavelengths.

Question 16

Primate color vision is especially good at discriminating shades of which of the following colors?

A) red
B) green
C) blue
D) yellow

Question 17

Which of the following features do not contribute to the protection of the human eye?

A) the bony orbits
B) tears
C) the placement of the eyes toward the front
D) blinking

Question 18

The color of an object that a human sees is a function of the wavelengths that are _________ the object.

A) refracted by
B) absorbed by
C) reflected by
D) passed through

Question 19

Photons

A) may be divided into smaller particles.
B) possess constant amounts of energy.
C) always travel at the same speed.
D) are too small to impact the visual systems of animals.

Question 20

The reason we do not perceive our eye blinks as "blackouts" might be that:

A) blinks happen too quickly to be perceived by the cerebral cortex.
B) during a blink,the visual cortex is inactivated.
C) we learn to ignore these interruptions in visual input.
D) during a blink,areas of the brain involved with consciousness become less active.

Question 21

Courtney suffered a corneal abrasion on one eye after she fell asleep with her hard contacts in place.When she asked her physician what to expect from her injury,the physician told her that

A) she would no longer be able to see from that eye.
B) she would need strong pain medications,as the cornea has a high density of pain receptors.
C) she wouldn't need any pain medication,because the cornea lacks pain reception.
D) her binocular depth perception would no longer function normally.

Question 22

The process of adjusting focus when looking at objects close up or at a distance is known as

A) accommodation.
B) assimilation.
C) transduction.
D) lateral inhibition.

Question 23

Which of the following animals are believed to shed emotional tears?

A) all animals
B) mammals and birds
C) humans and all other primates
D) humans,gorillas,and elephants

Question 24

The aqueous humor is located in the

A) anterior chamber.
B) vitreous chamber.
C) lens.
D) macula.

Question 25

Ashley's mother woke up one morning seeing rings of flashing light in one eye.Her doctor diagnosed the event as a "vitreous detachment." Although Ashley was unfamiliar with this condition until she looked it up in her search engine,she was able to tell her mother that it probably involved:

A) the pigmented tissue at the back of the eye that supports the photoreceptors.
B) a blockage of the tear ducts at the outer upper corner of the eye.
C) the fluid located in the main chamber of the eyeball.
D) the fluid located in the anterior chamber of the eyeball.

Question 26

Nick's grandfather has just been diagnosed with glaucoma,and was told by his doctor that this condition results from a blockage of fluid in the eye.Based on Nick's understanding of the anatomy of the eye,he was able to tell his grandfather that the blockage involves his

A) vitreous humor,which circulates around the cornea and lens.
B) aqueous humor,which circulates around the cornea and lens.
C) vitreous humor,located in the main chamber of the eyeball.
D) aqueous humor,located in the main chamber of the eyeball.

Question 27

The major interior chamber of the eye is known as the _________ chamber.

A) anterior
B) aqueous
C) vitreous
D) macular

Question 28

Pupil diameter

A) does not change.
B) adjusts to the temperature of the external environment.
C) responds only to the amount of light present in the environment.
D) responds to the amount of light present in the environment as well as the organism's emotional state.

Question 29

The hard,white outer covering of the eye is known as the

A) fovea.
B) macula.
C) sclera.
D) cornea.

Question 30

Relative to the actual image being viewed,the image reflected on the retina of the eye is

A) identical in its spatial orientation.
B) slightly elongated.
C) right side up and reversed.
D) upside down and reversed.

Question 31

Crying in response to emotional events might be especially useful in

A) deactivating parts of the brain involved with consciousness.
B) reducing blood pressure.
C) ridding the body of stress-related substances.
D) protecting the eye from dust and debris.

Question 32

The cornea obtains nutrients from

A) its own blood supply.
B) the aqueous humor.
C) the vitreous humor.
D) the blood supply of the iris.

Question 33

The lens obtains its nutrients from

A) its own blood supply.
B) the aqueous humor.
C) the vitreous humor.
D) the blood supply of the iris.

Question 34

Amber's mom is in her mid-40s,and she's starting to complain about how long it takes her to see well when she shifts her vision from the speedometer of her car to the road ahead of her.It is likely that Amber's mom is experiencing age-related deficits in the ability of her lens to

A) assimilate.
B) accommodate.
C) transduce.
D) laterally inhibit.

Question 35

The color of the iris is primarily a result of

A) its blood supply.
B) its pigmentation.
C) the refraction of light by the anterior chamber.
D) the reflection of light from the retina.

Question 36

The cornea and lens both remain clear,because

A) they consist of special proteins found only in the eye.
B) we habituate to the sight of their blood vessels.
C) neither has a blood supply.
D) their blood vessels contain clear plasma only.

Question 37

Anthony has dark brown eyes,and his sister Samantha has green eyes.It is likely that

A) Anthony's aqueous humor has a different composition than Samantha's.
B) Anthony's irises contain a denser blood supply than Samantha's.
C) Samantha's irises contain more melanin than Anthony's.
D) Anthony's irises contain more melanin than Samantha's.

Question 38

The aqueous and vitreous humors differ in that the

A) aqueous humor is replenished and the vitreous humor is not.
B) vitreous humor is replenished and the aqueous humor is not.
C) aqueous humor nourishes the cornea,whereas the vitreous humor nourishes the lens.
D) vitreous humor nourishes the cornea,whereas the aqueous humor nourishes the lens.

Question 39

Before reaching the retina,light must pass through the

A) retinal epithelium.
B) optic disk.
C) vitreous humor and several layers of neurons.
D) vitreous humor,blood vessels,and several layers of neurons.

Question 40

Which of the following structures is actually a clear extension of the sclera?

A) the fovea
B) the macula
C) the lens
D) the cornea

Question 41

The human blind spot results when light falls on the

A) fovea.
B) optic disk.
C) macula.
D) temporal retina.

Question 42

The fovea contains only

A) rods in all animals.
B) cones in all animals.
C) rods in primates.
D) cones in primates.

Question 43

Blood vessels and axons forming the optic nerve enter and exit the eye at the

A) optic disk.
B) macula.
C) fovea.
D) temporal retina.

Question 44

The area of the retina that lacks large blood vessels and is responsible for central vision is called the:

A) optic disk.
B) anterior chamber.
C) temporal retina.
D) macula.

Question 45

Ganglion cells form synapses with the amacrine and bipolar cells in the _________ layer.

A) inner nuclear
B) outer nuclear
C) inner plexiform
D) outer plexiform

Question 46

The axons of which type of cell form the optic nerve?

A) bipolar
B) amacrine
C) ganglion
D) horizontal

Question 47

Compared with photopic vision,scotopic vision is

A) highly sensitive to light and color.
B) less sensitive to light and color.
C) highly sensitive to light but not detail.
D) highly sensitive to detail but not light.

Question 48

Rods contain which of the following photopigments?

A) rhodopsin
B) cyanolabe
C) chlorolabe
D) erythrolabe

Question 49

The human eye contains approximately _________ million rods.

A) 6
B) 75
C) 100
D) 120

Question 50

The small pit within the macula,specialized for detailed vision,is known as the

A) optic disk.
B) epithelium.
C) fovea.
D) inner plexiform layer.

Question 51

The "red eye" that appears in some flash photography results from the

A) distortion of the eye's color by the aqueous and vitreous humors.
B) scattering of light from the iris of the eye.
C) reflection from the red epithelium behind the retina.
D) rich blood supply of the retina.

Question 52

Cell bodies of the photoreceptors are located in the _________ layer.

A) inner nuclear
B) outer nuclear
C) inner plexiform
D) outer plexiform

Question 53

The cell bodies of bipolar,amacrine,and horizontal cells are located in the _________ layer.

A) inner nuclear
B) outer nuclear
C) inner plexiform
D) outer plexiform

Question 54

Rods are responsible for _________ vision,which refers to our ability to see in _________ light.

A) scotopic;dim
B) scotopic;bright
C) photopic;dim
D) photopic;bright

Question 55

Bing has had a stroke that affected an area of his brain that serves his macula,including the fovea of both eyes.What should you expect his vision to be like?

A) He will be totally blind.
B) He will be able to see only what is exactly in front of him.
C) He will be able to see only what is in his peripheral visual area.
D) He will be able to see color,but not movement.

Question 56

We do not see the blood vessels and neurons that lie in front of the retina because

A) the visual system does not respond much to stimuli that never change.
B) these structures are made of special proteins whose fibers make them transparent.
C) they are blocked by the vitreous humor.
D) they lie behind the lens and cornea.

Question 57

The layer of pigmented cells supporting the photoreceptors in the retina is known as the

A) macula.
B) epithelium.
C) fovea.
D) ganglion layer.

Question 58

Photoreceptors absorb light in their

A) axons.
B) dendrites.
C) outer segments.
D) inner segments.

Question 59

Bipolar cells form synapses with horizontal cells and photoreceptors in the _________ layer.

A) inner nuclear
B) outer nuclear
C) inner plexiform
D) outer plexiform

Question 60

The type of retinal cells indicated by #3 in the image above are _________ cells.

A) ganglion
B) horizontal
C) bipolar
D) amacrine

Question 61

When rods are in the dark,cGMP keeps sodium channels _________ allowing sodium to _________ the cell.

A) open;enter
B) open;leave
C) closed;enter
D) closed;leave

Question 62

The human eye contains approximately _________ million cones.

A) 6
B) 75
C) 100
D) 120

Question 63

Eagles have only cones in their retinas.Assuming that what you have read in the text about rods and cones applies to eagles,you should expect eagles to be able to see

A) very well in the dark,enabling them to hunt at night.
B) movement from great distances,but not with much clarity,enabling them to see prey move.
C) very well,but only in black and white.
D) with great clarity and to see color,enabling them to distinguish prey from surroundings.

Question 64

On a night patrol with his platoon,Charles has been ordered to watch a house through night vision goggles and notify his commander when the front door opens.Suddenly his night vision goggles malfunction.Until he can figure out how to readjust them,he will see the door opening best if he

A) continues to look straight ahead at the door,focusing light on his foveas.
B) continues to look straight ahead at the door to use his scotopic vision.
C) focuses on a point to the left or right of the door in order to use his scotopic vision.
D) focuses on a point to the left or right of the door in order to use his photopic vision.

Question 65

When a rod absorbs a photon of light,retinal changes from the

A) 11-cis form to the all-trans form and merges with opsin to form rhodopsin.
B) all-trans form to the 11-cis form and merges with opsin to form rhodopsin.
C) 11-cis form to the all-trans form,and the rhodopsin molecule breaks apart.
D) all-trans form to the 11-cis form,and the rhodopsin molecule breaks apart.

Question 66

Compared with vision under direct sunlight,our ability to see detail under starlight is about

A) the same.
B) ten times better.
C) ten times worse.
D) one hundred times worse.

Question 67

While you are reading this test,your _________ vision is most active because of activity in your _________.

A) photopic;fovea
B) scotopic;fovea
C) photopic;ganglion
D) photopic;rods

Question 68

The potential of a rod's outer segment in complete darkness is approximately _________ mV.

A) -70
B) -30
C) +30
D) +70

Question 69

The process of translating a physical stimulus into action potentials is known as

A) transduction.
B) translation.
C) absorption.
D) the dark current.

Question 70

When we enter a darkened theatre,it takes a while before we can see our surroundings clearly.The most likely explanation for this phenomenon is that

A) the lens needs time to accommodate to the change in lighting.
B) the glutamate in rods has been depleted and more must be synthesized.
C) the visual system switches slowly between processing inputs from cones to inputs from rods.
D) it takes about 30 minutes for rhodopsin to regenerate after it has broken apart in response to light.

Question 71

Photoreceptors

A) are hyperpolarized in the dark and depolarized by light.
B) are depolarized in the dark and hyperpolarized by light.
C) produce action potentials in response to being in the dark.
D) produce action potentials in response to light.

Question 72

Photoreceptors release which of the following neurotransmitters?

A) substance P
B) serotonin
C) GABA
D) glutamate

Question 73

Gary's physician warned him that changes in his vision made it too dangerous for him to drive his car anymore after dark,although he would be perfectly safe during the daytime.Gary is probably experiencing deficits in his

A) color vision.
B) retinal disparity.
C) photopic vision.
D) scotopic vision.

Question 74

The periphery of the retina is superior to the center for viewing

A) colorful objects in bright light.
B) black and white objects in bright light.
C) objects in fine detail in dim light.
D) objects with less detail in dim light.

Question 75

As they walked on the beach on a starry night,Louise complimented her friend Josh on the color of his new sweater.It is most likely that Louise

A) saw the sweater earlier under brighter light,because she would be unable to see its color in the dark.
B) might not like the color of the sweater as well when she sees it under brighter light,because color vision in the dark is more reddish.
C) can see the color of the sweater perfectly well,as color vision is excellent even in starlight conditions.
D) is possibly colorblind,resulting in her "seeing" a color that she shouldn't be able to see at night.

Question 76

James is comparing recordings of a rod's reaction to a very bright light and a dim light.He soon observes that the bright light produces _________ in the rod than the dim light.

A) greater hyperpolarization
B) less hyperpolarization
C) greater depolarization
D) less hyperpolarization.

Question 77

Jennifer has been assessing the rate at which neurotransmitters are being released by a population of rods.So far she has observed a very low rate of release,which most likely means that the rods are

A) completely in the dark.
B) being exposed to dim light.
C) being exposed to bright light.
D) no longer functioning normally.

Question 78

Jessica's vision is 20/20,but her friend Joshua needs to wear glasses to correct for his 20/200 vision.Without his glasses,Joshua sees as much detail in objects that are 20 feet away from him as Jessica sees in objects that are _________ feet away from her.

A) 10
B) 20
C) 200
D) 2,000

Question 79

Cones are responsible for _________ vision,which refers to our ability to see in _________ light.

A) scotopic;dim
B) scotopic;bright
C) photopic;dim
D) photopic;bright

Question 80

Moving from the fovea to the outer margins of the retina,

A) rods and cones are evenly distributed.
B) the concentration of rods decreases and the concentration of cones increases.
C) the concentration of cones decreases and the concentration of rods increases.
D) rods and cones are concentrated in distinct clusters.