Chapter 7: Vision

Question 1

Sensation definition

Answer 1

The process by which the nervous system takes in information from the environment

Question 2

Sensation is “_______” of the system

Answer 2

Biology

Question 3

Perception definition

Answer 3

The manner in which the brain interprets incoming sensory information.

Question 4

Perception is the “_______” of the system

Answer 4

psychology

Question 5

Our perceptions differ _______ from the ________ properties of stimuli.

Answer 5

qualitatively; physical

Question 6

How much information does the nervous system from stimulus?

Answer 6

Only some

Question 7

What does nervous system take into account when it interprets information?

Answer 7

Earlier experiences

Question 8

Three properties of all sensory systems

Answer 8

Reception, transduction, and coding

Question 9

Reception definition

Answer 9

The absorption of physical energy by specialized neurons (sensory receptors)

Question 10

Law of specific nerve energies

Answer 10

Any activity in a particular sensory nerve always conveys the same type of information to the brain

Question 11

Transduction definition

Answer 11

The conversion of physical energy into electrochemical patterns of activity

Question 12

Receptor potential

Answer 12

local depolarization or hyperpolarization

Question 13

What is specialized in sensory neurons?

Answer 13

Graded potential

Question 14

Coding definition

Answer 14

One-to-one correspondence between the physical stimulus and nervous system activity

Question 15

Coding is also ______ of sensation and ________ of stimulus

Answer 15

meaning; perception

Question 16

What absorbs physical energy in the visual system?

Answer 16

Visual receptor cells

Question 17

What is the physical stimulus for visual receptor cells?

Answer 17

Photon of light

Question 18

How can photons of light vary?

Answer 18

wavelength; nm

Question 19

Where does light enter eye?

Answer 19

Through pupil

Question 20

What happens after light enters the eyes?

Answer 20

Image is focused by lens

Question 21

What happens after image is focused by lens?

Answer 21

It is projected to back or retina

Question 22

Compare actual image to retinal image

Answer 22

Retinal image is upside down and backwards.

Question 23

What does fovea do?

Answer 23

Maximal acuity

Question 24

Where is the fovea in humans?

Answer 24

Back of pupil

Question 25

Laminar organization of the cells in the retina

Answer 25

It is inside out and light passes through ganglion and bipolar cells before reaching photoreceptors.

Question 26

What do axons of ganglion cells form?

Answer 26

Optic nerve and Cranial nerve II

Question 27

Blind spot

Answer 27

• Where optic nerve exits

- No receptor cells

Question 28

How many rods synapse on ganglion cells?

Answer 28

Many to one

Question 29

Is there high acuity with rods? especially under what conditions?

Answer 29

No high acuity; dim light

Question 30

Where are the rods?

Answer 30

Concentrated in periphery of retina

Question 31

How many cones synapse on ganglion cells?

Answer 31

fewer to one

Question 32

Is there high acuity with cones? Under what conditions?

Answer 32

High acuity; bright light, color, detail

Question 33

Where are the cones?

Answer 33

Concentrated in fovea

Question 34

When activated, graded release of transmitter is proportional to __________ . It is also like _______

Answer 34

• intensity of light

- receptor potential

Question 35

Are there action potentials before ganglion cells?

Answer 35

No

Question 36

Photopigments

Answer 36

chemicals that release energy

Question 37

What is 11-cis retinal and opsin?

Answer 37

11-cis retinal is a light absoring molecule and opsin is a protein

Question 38

What happens when light hits opsin-retinal molecule?

Answer 38

The 11-cis retinal changes conformation to all-trans retinal.