Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Physiology > PNS, CH 6 > Flashcards

PNS, CH 6 Flashcards

(76 cards)

Start Studying
1
Q

Nervous system composed of Efferent and Afferent fibers

A

Peripheral Nervous system

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

Stimuli exist in what modalities

A

light, sound, pressure, chemical changes

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

Sensory receptors

A

Specialized peripheral endings of afferent neurons

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

Sensory receptors convert stimulus energy into what form for communication to CNS

A

electrical signals through sensory transduction

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

Receptor potentials are what type of potential

A

graded potential

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

Each type of receptor responds to how many types of signals?

A

its one adequate stimulus

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

Photoreceptors

A

responsive to visible wavelengths of light

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

Mechanoreceptors

A

sensitive to mechanical energy, ie. stretch, blood pressure, ear hairs bent from sound waves

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

Thermoreceptors

A

sensitive to heat and cold

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

Osmoreceptors

A

detect changes in solute concentrations in body fluids and resultant changes in osmotic activity

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

Chemoreceptors

A

sensitive to specific chemicals; includes receptors:
for smell and taste, detect O2 and CO2 in blood,
detect chemical content of digestive tract

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

nocieceptors

A

pain receptors that are sensitive to tissue damage or distortion of tissue.

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

Use for Sensory Information

A

regulating motor behavior in response to external environment, maintaining homeostasis, cortical arousal and consciousness, perceptions of the world around us due to sensory information, changing emotional states

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

Two forms of sensory receptors

A
  1. Specialized end of an afferent neuron

2. Separate receptor cell associated with the peripheral end of the neuron

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

steps to creating a graded Receptor potential in separate receptor cell

A
  1. A stimulus brings about a graded, depolarizing receptor potential promoting net Na+ entry.
  2. Local depolarization opens Ca+ channels.
  3. Ca+ entry triggers exocytosis of neurotransmitter.
  4. Neurotransmitter binds to afferent neuron opening Na+ channels on the neuron causing depolarization.
  5. Receptor potentials if strong enough generate action potentials.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

steps to creating graded receptor potential in specialized afferent ending

A
  1. A stimulus brings about a graded, depolarizing receptor potential promoting net Na+ entry.
  2. Local flow from depolarized receptor ending opens the neurons voltage gated Na+ channels.
  3. Receptor potentials if strong enough generate action potentials.
    These action potentials move along the afferent fiber to the CNS.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the difference in action potential initiation sites between afferent and efferent neurons

A

Efferent: At the axon hillock located at the start of the axon next to the cell body
Afferent: Peripheral end of the nerve fiber, away from the cell body

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

How does the magnitude of receptor potential correlate to action potential?

A

The greater the stimulus, the larger the receptor potential, the more frequent action potentials are generated

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

What are the types of receptors classified according to their adaptation

A
  1. Tonic receptors: do not adapt at all or adapt slowly

2. Phasic receptors: rapidly adapting receptors

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

Receptive field

A

refers to the area surrounding a receptor within which the receptor can detect stimuli.

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

How does the acuity of a body region correlate to the size of the receptive field?

A

The acuity of a body region varies inversely with the size of its receptive fields.

  1. Smaller receptive fields show higher acuity.
  2. Acuity is also influenced by lateral inhibition.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Visceral afferent

A

Signals coming from internal organs used for homeostasis, subconscious

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

Sensory Afferent

A

conscious sensory information derived from

  1. Somatic sensation: arising from the body surface, and proprioception from muscles joints and inner ear
  2. special senses: vision, taste, smell, etc.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Lateral inhibition

A

Facilitates the localization of a stimulus by inhibiting the pathways next to the receptive field.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Perception
is the conscious interpretation of the external world.
26
Why is it that the brains perception from its input is an abstraction and not reality.
The only stimuli that can be detected are those for which receptors are present. We can only perceive a small range of smell, taste, sound, color, etc.
27
3 Categories of nocieptors
Mechanical, thermal, polymodal
28
What are the two layers of dermis
1. Papillary: 20%: means going down (fingerlike) | 2. Reticular: 80%
29
How many epidermis layers
5. Top is corneum which is dead and sloughs off | Bottom is Basale which is very active and continues mitosis
30
How long does it take a cell to go from Basale to coroneum?
usually 30 days
31
Psoriasis
Cells moving from basal layer to the top in only 10 days, outter layer of the skin is still living which causes the irritation and itching
32
Ruffini endings
tactile receptor which detects stretching and deep pressure
33
Hair receptors
tactile receptor which detects hair movement and light touch
34
Merkels disc
tactile receptor which detects light sustained touch
35
Pacinian corpuscle
vibrations and deep pressure
36
Missners corpuscle
light fluttering touch
37
Pain pathway in the body
Afferent pain fibers terminate in the spinal cord on ascending pathways that transmit the signal to the brain
38
What is the spinal cord pain neurotransmitter
substance P
39
What is the bodies analgesic system?
Inhibitory interneurons in the dorsal horn release Endogenous opiods with block the release of Substance P
40
Where is pain perceived in the brain?
Thalamus
41
What part of the brain is responsible for the behavioral and emotional responses to pain
hypothalamus and limbic
42
What types of neuron fibers are associated with the transmission of pain
A - Myelinated, large diameter B - Myelinated, medium diameter C - unmyelinated and small diameter
43
What type of fiber transmits slow pain, fast pain?
Fast pain is A delta, Slow is C
44
Three tissue layers of the eye
Sclera/cornea, Choroid/ciliary body/iris, retina
45
Tough outer layer of the eye
sclera
46
anterior outer portion of the eye
cornea
47
Highly pigmented middle layer which is contains blood vessels
choroid
48
Anterior middle layer of the eye
ciliary body and iris
49
Innermost coat containing an outer pigmented and inner nervous tissue layer with the rods and cones
retina
50
Two fluid filled cavities divided by the lens
Aqueous humor (anterior) and vitreous humor (posterior)
51
function of ciliary body
controls the shape of the lens and creates the aqueous humor
52
Canal of schlem
where aqueous humor is released
53
Glacoma
too much aqueous humor, doesn’t drain fast enough. This creates a pressure on the optic nerve and can cause blindness
54
primary refractive structures that bend incoming light rays.
Cornea and Lens
55
Accommodation
Ability to adjust strength of lens by changing its shape. | Shape is regulated by ciliary muscle
56
presbyopia
Age-related reduction in accommodation ability due to the lens becoming brittle and cell death
57
What happens to the lens when the ciliary muscle is contracted
the suspensory ligaments become slack, reducing the tension on the lens, allowing it to assume a stronger, rounder shape because of its elasticity allowing the eye to focus for stronger near vision
58
What happens when the ciliary muscle is relaxed
the suspensory ligaments are taut, putting tension on the lens so that it is flat and weak for far vision
59
What type of autonomic stimulation controls lens contraction?
Sympathetic relaxes, parasympathetic contracts
60
Emmetropia
Normal eye: far source doesn't need accommodation and near sources of light are focused on the retina with accommodation (changing the shape of lens)
61
Myopia (minus prescription)
Nearsightedness: Eyeball is too long or the lens is too strong. 1. Uncorrected (no glasses) - Far source focus falls in front of the retina without accommodation - near source is fine with accommodation 2. Corrected with concave lens (brings back to normal eye) - Far source is focused on retina without accommodation - Near source on retinal with accommodation
62
hyperopia (plus prescription)
Farsightedness: Eyeball is too short or the lens is too weak 1. Uncorrected (No glasses) - Far source focused on retina with accommodation - Near source is focused behind retina even with accommodation 2. Corrected with Convex lens (brings back to normal eye - Far source focused on retina without accommodation - Near source focused on retina with accommodation
63
Three types of cells in the neural layer of the retina
Rods and cones, bipolar, and ganglion
64
Rods and cones
Photoreceptor cells that make up the outer most layer of the retina
65
Bipolar cells
middle layer of the retina with associated interneurons
66
Ganglion cells
inner layer of retina, axons of the ganglia form the optic nerve
67
Optic disk
slightly off center spot where the optic nerve leaves the eye and blood vessels pass through
68
Another name for the optic disk
Blind spot, because it is void of rods and cones
69
Properties of rods
120 million, concentrated on the periphery, High sensitivity, low acuity, night vision, shades of grey, convergence in retinal pathways
70
Properties of cones
6 million, concentrated in fovea, low sensitivity, high acuity, day vision, colors, low convergence on retinal pathways
71
small depression in center of retina which has only cones, no bipolar or ganglion cells and is the point of most distinct vision
Fovea
72
area immediately surrounding fovea which has cones, bipolar, and ganglion cells. Has fairly high acuity
Macula lutea
73
A photopigment consists of two components
1. opsin, an integral protein in the plasma membrane | 2. retinal, a derivative of vitamin A that absorbs light
74
Age related Maculardegeneration (AMD)
leading cause of blindness in Western Hemisphere. Loss of photoreceptors in macula lutea causing "doughnut vision"
75
Three segments of rods and cones
Outer, inner, and synaptic terminal.
76
Outer segment
Faces Choroid detects light stimulus Rod or cone shaped Consists of flattened membranous disks full of photopigments

Physiology (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions