Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AcaDec 2023_24 > Science Section 3 - additional > Flashcards

Science Section 3 - additional Flashcards

1
Q

What is the vestibular system?

A

the sensory system comprised of components in the inner ear that provides the brain with information about motion and position; creates the sense of balance and spatial orientation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Sensory transduction

A

process of translating light, sound, or pressure into electrochemical signals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is proprioception?

A

the sense of where your body is in a space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Receptive field

A

region where a sensory receptor can detect a stimulus (specific to each sensory receptor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the retina?

A

the thin layer at the back of the eyeball where there are rods and cones for phototransduction to take place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cornea

A

the front, transparent layer of the eye where refraction of light takes place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is refraction?

A

bending or focusing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the iris?

A

the circular, pigmented muscle that controls the size of the pupil in the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

When does the pupil/iris dilate?

A

in dim or low light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When does the pupil/iris contract to reduce its size?

A

in bright lights

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the function of the lens in the eye?

A

further refracts light to focus the image on the retina by changing its shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Reduction to the len’s flexibility becaues of aging causes what?

A

farsightedness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is myopia?

A

Nearsightedness; occurs when the distance between the retina and cornea is too long so the image focus falls in front of the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Function of photoreceptors

A

to receive and transduce light in the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Pigmented epithelium

A

a pigmented cell layer just outside the retina that works to support the function of photoreceptors, for example, by absorbing excess light and getting rid of broken photoreceptor cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the choroid?

A

network of blood vessels outside the pigmented epithelium layer that brings oxygen and nutrients to the photoreceptor cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Fovea

A

center of the retina where vision is the most acute or sharpest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Function of rods

A

used for peripheral and low light vision as they have more disks and are located outside of the center of the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Function of cones

A

Respond to bright lights and are located in the fovea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are opsins?

A

pigments that absorb different wavelengths of color

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What type of opsins do rods use?

A

rhodopsin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Short waves of light are usually what color?

A

blue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Medium wavelengths of light are usually what color?

A

green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Long wavelengths of light are usually what color?

A

red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How many types of cones are there?

A

3 with each responding to one of the certain colors (red, green, or blue), trichromatic theory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is absorption spectra?

A

refers to different opsin in cone receptors that will respond to different wavelengths of light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

When light hits the opsin the cell is depolarized or hyperpolarized?

A

Hyperpolarized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

The cell is ___________ in the absence of light

A

depolarized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Describe the process when light is absorbed by the opsin

A

1). The molecules shape inside changes, activating opsin 2). Which encounters a G-protein that will then eventually activate enzyme phosophodiesterase. This enzyme then breaks down cGMP that leads to there not being enough of it to bind to the ion channels, leading them to close and stop the influx of sodium and calcium that makes the membrane potential more positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the function of cGMP?

A

aka cyclic guanosine monophosphate; a molecule that keeps certain ion channels open

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Describe the process when there is an absence of light

A

The photoreceptor cells release glutamate that will bind to receptors on the bipolar cells which will then synapse on retinal ganglion cells whose axons exit the eyes as the optic nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Bipolar cells

A

connect photoreceptor cells to ganglion cells in the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Amacrine cells

A

distribute info. from one bipolar cell to many ganglion cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Horizontal cells

A

form connections between one central rod or cone to many distant photoreceptors and several bipolar cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What happens if a photoreceptor depolarizes a horizontal cell?

A

the horizontal cell inhibits the distant bipolar cells (aka lateral inhabitation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is lateral inhabitation?

A

the capacity of excited neurons to reduce the activity of their neighbors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Center-surround receptive fields

A

a visual receptive field with a circular center region and a surround region; stimulation of the center has the opposite effect on surrounding areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Purpose of lateral inhabitation/center-surround receptive fields

A

to sharpen the edges and enhance the contrast in images by amplifying edges and borders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What allows for highly acute vision in the fovea?

A

Small receptive fields; the horizontal cell connects fewer retinal ganglion cells to a single photoreceptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Receptive fields in the ________ parts of the retina are larger and provide _______ sharp vision

A

peripheral, less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the retinofugal pathway?

A

connects the retina to the visual cortex through the lateral geniculate nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

The name for the retinofugal pathway comes from

A

the Latin word “fugit” which means “fleeing”

43
Q

Optic chiasm

A

point where axons from both eyes come together; only the axon close to the nose (inner) crosses to the other side while the outer axon comes out the same side

44
Q

Optic tract

A

continuation of the optic nerve; the axons that bring visual info. to V1 after the optic chiasm

45
Q

What is binocular vision?

A

vison that incorporates vision input from both eyes into a single image, done by comparing how an object’s appearance differs from the left and right eye to calculate depth perception

46
Q

What is the LGN of the thalamus?

A

aka lateral geniculate nucleus that is specialized for processing visual input

47
Q

Describe the LGN

A

Information from both eyes are not mixed and cells that are specialized for detecting fine detail and color, for example, are separated into distinct layers. Cells do use lateral inhibitation and maps out the same way as the retina.

48
Q

Another important function of the LGN of the thalamus

A

Receiving info. from the eyes and other areas of the brain, it decides how to send information to the occipital love. For example, it may inhibit background info. if it is not what you are focusing on (figure-ground) or it won’t send info. if you are asleep

49
Q

How many layers does the primary visual cortex have?

A

six

50
Q

Input to what goes to layer four of the primary visual cortex?

A

the cerebral cortex

51
Q

Most input goes to what layer of layer four in the V1?

A

4C

52
Q

What type of neurons are found in layer 4C of the V1?

A

Spiny stellate neurons whose dendrites are covered in spines to maximize the number of synapses it has

53
Q

Pyramidal cells

A

are found in other layers of V1 that have one long axon and dendrite to send inputs across longer distances

54
Q

What is another names for the primary visual cortex?

A

striate cortex

55
Q

Does binocular or monocular information from the LGN enter layer 4C of the V1?

A

Monocular. Information from the two eyes begin to mix once the info. moves beyond layer 4C

56
Q

Other ways neurons in V1 are depolarized?

A

by specific orientations of light, direction, and color orientation

57
Q

What is the retinotopic map?

A

a map of visual information from the retina onto neurons in the visual cortex and LGN. The central part is represented in the back and peripheral regions are represented further forward

58
Q

The left side of the visual cortex represents?

A

the right half of the visual field (and vice versa)

59
Q

The image in V1 is _______ and ________

A

upside down, backward

60
Q

What is corticol magnification?

A

refers to the fact that the number of neurons in the visual cortex responsible for processing an object of a given size in the visual field varies as a function of the location of the stimulus in the visual field; items appear larger in the center of field (imaged on the fovea and are processed by a larger amount of neurons) and objects to the side are smaller and processed by fewer neurons in V1

61
Q

Where does visual input go after being processed by V1?

A

Extrastriate cortex

62
Q

What is the extrastriate cortex?

A

a region of the occipital lobe surrounding the primary visual cortex that is involved in high resolution vision and object recognition

63
Q

Visual information about location and motion is sent from V1 to?

A

Top or dorsal parts of the occipital and parietal lobe that specialize in processing aspects of vision including spatial orientation, depth perception, and location/velocity/direction of an object. The dorsal stream of info. processes info. about the “where” of visual stimuli

64
Q

What is area MT?

A

region of cortex in the parietal lobe that deals with motion perception

65
Q

Direction-selective neurons

A

these neurons in area MT fire action potentials maximally when they detect movement in a particular direction

66
Q

What happens if area MT is damaged on both sides of the brain?

A

It can lead to akinetopsia (motion blindness). People with this condition see moving objects are rapidly shifting still frames, similar to a flip book

67
Q

Bottom (ventral) regions of the occipital and parietal lobe receive what type of information from V1?

A

color, shape, and form. These regions deal with the recognition of faces, objects, symbols, text, and visual objects. Process the “what” of stimuli

68
Q

Damage to the ventral visual stream can result in

A

difficulty recognizing visual objects

69
Q

What is visual agnosia?

A

impairment with recognizing objects via only vision and is caused by damage to areas of the temporal lobe that deal with object recognition

70
Q

What is prosopagnosia?

A

face blindness; patients cannot recogonize others by facial features

71
Q

What is parallel processing?

A

the ability of the brain to simultaneously process incoming stimuli, including
color, motion, shape, and depth, separately by different cells at all levels of the visual system

72
Q

The ear is also known as

A

pinnae

73
Q

What is sound and how does it vary?

A

It is a series of pressure changes in the air and vary in frequency (pitch) and intensity (volume)

74
Q

What is the tympanic membrane?

A

a membrane at the end of the
auditory canal that moves in response to variations in air pressure caused by soundwaves; also called the ear
drum

75
Q

What is the middle ear?

A

transfers and magnifies sound waves from
the ear canal and ear drum to the inner ear, where the sound waves are transduced

76
Q

What are the ossicles?

A

the small bones found in the middle ear that
act like a series of levers to transfer and magnify the sound waves from the ear drum to the cochlea of the inner ear

77
Q

What connects the middle ear with the back of the throat?

A

eustachian tube

78
Q

Name the three ossicles

A

hammer (malleus), anvil (incus), and stirrup (anvil)

79
Q

Function of the cochlea (inner ear)

A

transduces sound

80
Q

Cochlea is Latin for

A

“snail” because of its spiral shape

81
Q

Function of the semicircular canals (inner ear)

A

as a major part of the vestibular system, they allows us to know where we are in a space and are critical for balance (along w/the utricle and saccule structures)

82
Q

What protects/encases the structures of the inner ear?

A

the labyrinth which is a bony and hollow structure

83
Q

What is the oval window?

A

outside of the cochlea that transfers the physical movement created by a sound wave on the tympanic membrane via the ossicles to the liquid inside the membrane that’ll travel inside the cochlea before bulging out the round window to relieve pressure

84
Q

What are the 3 fluid filled cavities in the cochlea?

A

the scala vestibuli at the top, the scala tympani at the bottom, and the scala media in the middle. Each of which are separated by a membrane

85
Q

What hollow cavities of the cochlea does the basilar membrane separate?

A

scala tympani (bottom) and scala media (middle

86
Q

How does the width/stiffness of the basilar membrane change?

A

it is stiffer/narrower at the outside of the spiral (where the cochlea is the widest) and floppier/wider at the center (apex) of the spiral where the cochlea is the narrowest

87
Q

Different stiffness of the basilar membrane means?

A

its different regions will maximally vibrate at different frequencies of waves through the fluid

88
Q

Where do high frequency sounds vibrate the basilar membrane?

A

oval window (near the entrance port)

89
Q

Where do low frequencies sounds vibrate the basilar membrane?

A

farther long the membrane

90
Q

How does the basilar membrane and Organ of Corti move when the stapes pushes a wave into the fluid of the scala vestibuli?

A

They move along with the sound wave

91
Q

What is the Organ of Corti?

A

the structure in the cochlea of the inner
ear in which the hair cells are found and where auditory transduction takes place

92
Q

What are stereocilia?

A

tiny hair like protrusions found on the hair cells of the Organ of Corti that are embedded in the tectorial membrane

93
Q

What is the tectorial membrane?

A

Located above the organ of Corti
in the cochlea, in which the tips of the stereocilia of the hair cells are embedded, this membrane helps them create the back-and-forth movement of the cilia
required for sound transduction as it does not move along w/the sound waves

94
Q

The hair cells and organ of Corti are bathed in what?

A

Endolymph, which fills the scala media and has a high ion concentration of potassium

95
Q

What happens to the cilia of the inner hair cells when the Organ of Corti moves up and down?

A

They are bent back and forth which opens and closes small ion channels via connectors known as tiplinks. When they are bent forward, the tip links open the potassium channel which causes depolarization leading to voltage gated calcium channels to open that’ll then cause a neurotransmitter to be released at the basal end of the hair cell. If this happens, then an action potential happens in the dendrites of cochlear nerve neurons which brings auditory info. to the brain

96
Q

How do hair cells differ from most other neurons?

A

there is a higher concentration of potassium outside the cell vs the inside

97
Q

Function of outer hair cells

A

cells of the inner ear featuring
stereocilia, or long hair-like appendages, that can extend or contract to magnify the vibration of the basilar membrane, which helps the cochlea transduce with high sensitivity and accuracy

98
Q

Auditory pathway info. vs visual pathway info.

A

Information from both ears are mixed together when traveling the brain while info. from the eyes is kept separate

99
Q

Interaural intensity difference

A

your brainstem can use the sound shadow caused by head to calculate where the sound came from (if a sound originates from the left ear, it’ll sound louder on the left than the right)

100
Q

Interaural time delay

A

ex: if a sound originates on the left side of your head, then its signal will reach the auditory nuclei in the brainstem faster than the same info. travelling from the right side

101
Q

Inferior colliculus

A

a cluster of grey matter found in the
brainstem that forms an important relay station for auditory information on its way to the brain

102
Q

Medial geniculate nucleus (MGN) of the thalamus

A

the region or nucleus of the
thalamus used to relay auditory information to the cerebral cortex it is thought to influence the direction and maintenance of attention

103
Q

Where is the primary auditory cortex located?

A

found in the insular cortex which is tucked in the fold between the temporal and parietal lobes

104
Q

Tonotopic mapping of A1

A

the map of the auditory cortex matches the mapping of the basilar membrane and organized by pitch (similar to the Organ of Corti, neurons in A1 have a particular pitch or frequency they’ll maximally respond to) and some neurons are intensity tuned (they’ll give a peak response to a particular volume)

AcaDec 2023_24 (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions