Brainscape's Knowledge GenomeTM

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


See full index

ANP1106 > Sensation and sensory receptors > Flashcards

Sensation and sensory receptors Flashcards

1
Q

The peripheral nervous system is divided into ________ and __________divisions.

A

sensory input and motor output

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

The motor output of the PNS is divided into _________ and ________ divisions

A

somatic (neuromuscular), autonomic

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

The outputs within the autonomic division of the PNS are further subdivided into _______ and
________ divisions

A

sympathetic, parasympathetic

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

What is the PNS? Function?

A

all neural structures outside the brain and spinal cord. It includes sensory receptors, peripheral nerves, associated ganglia, autonomic nervous system and motor endings.

Provides links to and from the CNS and the external environment

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

_________ are specialized to respond to changes in their environment,
which are called _____. Typically, activation of this by an adequate
stimulus results in ________that in turn trigger nerve impulses along the
afferent PNS fibers coursing to the CNS.

A

Sensory receptors
stimuli
graded potentials

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

What is sensation

A

ascending pathways, occur in the brain/ awareness of stimulus
/changes in the internal and external environment

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

What is perception

A

(interpretation of the meaning of the stimulus), occur in the brain/
conscious interpretation of those stimuli/ cerebral cortex interpretation of sensory input

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

What are the three ways to classify sensory receptors

A
  1. the type of stimulus they detect
  2. their body location
  3. their structural complexity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 5 categories of receptor classification by stimulus type

A
  1. Mechanoreceptors
  2. Thermoreceptors
  3. Photoreceptors
  4. Chemoreceptors
  5. Nociceptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are mechanoreceptors

A

respond to mechanical force such as touch, pressure (including blood pressure), vibration, stretch, and itch (causing the deformation of the membrane of the sensory ending)

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

What are thermoreceptors

A

sensory receptors that are sensitive to temperature change

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

What are photoreceptors

A

sensory receptors that are sensitive to light

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

What are chemoreceptors

A

sensory receptors that respond to chemicals in solution (molecules smelled or tasted, or changes in blood or interstitial fluid chemistry

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

What are nocioceptors

A

sensitive to pain-causing stimuli (extreme heat, extreme cold, excessive pressure, and inflammatory chemicals are all interpreted as painful). These signals stimulate subtypes of thermoreceptors,
mechanoreceptors, and chemoreceptors

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

What are the three categories of receptor classification by location

A
  1. Exteroceptors
  2. Interoceptors
  3. Proprioceptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are exteroceptors

A

receptors that Respond to stimuli arising outside the body (extero= outside)
❑ Found near the body surface
❑ Including skin and most receptors of the special senses (vision, hearing, equilibrium,
smell, and taste)
❑ Sensitive to touch, pressure, pain, and temperature receptors

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

What are interoceptors

A

Also called visceroceptors
❑ Respond to stimuli arising within the body (intero= inside)
❑ Found in internal viscera and blood vessels
❑ Sensitive to chemical changes, tissue stretch, and temperature changes
❑ Sometimes their activity causes us to feel pain, discomfort, hunger, or thirst

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

What are proprioceptors

A

Respond to internal stimuli
❑ Found in: skeletal muscles, tendons, joints, ligaments, and connective tissue
coverings of bones and muscles
❑ Respond to degree of stretch of the organs they occupy
❑ Give information concerning movements and position of the body

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

The________ is one type of
proprioceptor that provides information about
changes in muscle length

A

muscle spindle

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

What are the two categories for receptor classification based on structure

A

Either simple or complex

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

What are simple receptors? Function? Location?

A

Most receptors are simple.

they mostly belong to the
general senses ((a mix of touch, pressure, stretch, and vibration) and are simply the modified dendritic endings of sensory neurons.
They are found throughout the body and monitor most types of general sensory information

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

What are complex receptors? function? Location?

A

Complex receptors are special sense (vision, hearing, equilibrium, smell, and taste) organs in contact with a free nerve ending.

Housed in complex sense organs. For example, the eye or the ear

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

What are non-encapsulated nerve endings? Location, Function?

A

They are simple, bare endings of neurons. Most of them are non-myelinated group C fibers with knobs at the end.

Location: They are widespread in various tissues throughout the body, particularly in epithelial and connective tissues.

Function: nociception, thermoreception, mechanoreception. They are responsible for the sensations of itch and different temperature ranges. Nociceptors within this group can detect harmful stimuli, potentially causing pain, such as extreme heat or cold, pinching, or certain chemicals.

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

What are two examples of non-encapsulated nerve endings

A
  1. Epithelila tactile complexes (merkel cells and discs)
  2. Hair follicle receptor
25
Q

What are encapsulated nerve endings

A

All encapsulated nerve endings consist of one or more fiber terminals of sensory neurons enclosed in a connective tissue capsule

❑ All encapsulated receptors are mechanoreceptors
❑ They vary greatly in shape, size, and distribution in the body

26
Q

What are the 6 types of encapsulated nerve endings

A
  1. Tactile (Meissner’s) Corpuscles:
  2. Lamellar (Pacinian) Corpuscles:
  3. Bulbous (Ruffini) Corpuscles:
  4. Muscle Spindles:
  5. Tendon Organs:
  6. Joint Kinesthetic Receptors:
27
Q

What are tactile corpuscles

A

Found just below the skin, especially in areas sensitive to touch like fingertips.
Detect light touch and texture by feeling light pressure and low-frequency vibrations.
Help in discriminative touch, allowing us to distinguish different shapes and textures.

28
Q

What are lamellar corpuscles

A

Located deeper in the skin and in the fascia (a type of connective tissue).
Sense deep pressure and high-frequency vibration.
They respond quickly to changes in pressure, making them good at detecting vibrations or an “on/off” touch.

29
Q

What are Bulbous (Ruffini) Corpuscles

A

Found in both the skin and deeper connective tissues, including joint capsules.
Detect sustained deep pressure and skin stretch.
They resemble tendon organs, which monitor muscle stretch, indicating they may serve a similar function in sensing continuous pressure.

30
Q

What are Muscle Spindles

A

Found within the perimysium surrounding skeletal muscle fascicles.
They are proprioceptors that sense muscle stretch and initiate a reflex to resist that stretch.

31
Q

What are Tendon Organs

A

Located at the junction between muscles and tendons.
Detect tension within the tendon when the muscle contracts and initiate a reflex that causes the muscle to relax.

32
Q

What are Joint Kinesthetic Receptors:

A

Proprioceptors found in the capsules of synovial joints.
Help monitor joint position and movement, providing a sense of body position and movement (kinesthesia).

33
Q

Activation of sensory receptors results in_______ that trigger
________ impulses along the _______ to the CNS

A

graded depolarizations
action potentials
nerve axon

33
Q

Where does reflex activity take place

A

spinal cord

33
Q

where does sensation and perception occur

A

cerebral cortex

34
Q

What two things must happen for a sensation to occur

A
  1. The stimulus energy must match the specificity of the receptor.
  2. The stimulus must be applied within a sensory receptor’s receptive field—the area the receptor monitors.
34
Q

Typically, the smaller the receptive field, the _____ the ability
of the brain to accurately localize the stimulus site.

A

greater

34
Q

What are the 2 steps that occur after a stimulus has excited a receptor

A
  1. Transduction: The stimulus energy must be converted into the energy of a graded potential
  2. Receptors can produce one of two types of graded potentials.
35
Q

What are the two types of graded potentials a receptor can produce? What is it based on?

A
  1. A generator potential: When the receptor region is part of a sensory neuron
  2. Receptor potential: When the receptor is a separate cell (as in most special senses)
36
Q

The key to the physiological process of sensation is _______

A

transduction

37
Q

What is a nerve

A

a cordlike organ that is part of the peripheral nervous system

38
Q

What are the two classifications of nerves? What are they based on

A

either cranial or spinal depending on whether they arise from the brain or spinal cord

39
Q

What does every nerve consist of

A

parallel bundles of peripheral axons (some myelinated, some not) enclosed by successive wrappings of connective tissue

40
Q

Describe the wrappings of a nerve

A

Each axon (or nerve fiber) is surrounded by endoneurium, a delicate layer of loose connective tissue

A coarser connective tissue wrapping, the perineurium, binds groups
of axons into bundles called fascicles.

A tough fibrous sheath, the epineurium, encloses all the fascicles to form the nerve

41
Q

What are the three types of nerves in terms of the direction in which they transmit impulses

A

❑ Mixed nerves contain both sensory and motor fibers and transmit
impulses both to and from the central nervous system.
❑ Sensory (afferent) nerves carry impulses only toward the CNS.
❑ Motor (efferent) nerves carry impulses only away from the CNS.

42
Q

Most nerves are _____

A

mixed

43
Q

What are ganglia

A

collections of neuron cell bodies associated with nerves in the PNS

44
Q

what are nuclei

A

collections of neuron cell bodies in the CNS

45
Q

Ganglia associated with afferent nerve fibers contain cell bodies of ________. (These are the dorsal root ganglia.).

A

sensory neurons

46
Q

Ganglia associated with efferent
nerve fibers mostly contain cell bodies of __________

A

autonomic motor neurons

47
Q

axons of _________ can
regenerate but axons in the ____ cannot

A

peripheral nerves
CNS cannot

48
Q

What are the 4 steps for which PNS axons regenerate by

A
  1. The axon fragments (seals itself off)
  2. Schwann cells and macrophages clean out the dead axon
  3. Axon filaments grow through a regeneration tube
  4. The axon regenerates and a new myelin sheath forms
49
Q

Why do CNS axons not regenerate

A

Oligodendrocytes, the supporting cells of the CNS, are studded with growth-inhibiting proteins.

50
Q

What is a dermatome

A

Sensory territories on the surface of the body are organized into band-like sensory territories

51
Q

What is the function of a dermatome

A

areas of skin that send signals to
the brain through the spinal nerves. The dermatome system covers the entire body from the hands and fingers to the feet and toes

52
Q

There are _ cervical nerves, __thoracic nerves, __
lumbar nerves and __ sacral nerves.

A

8, 12, 5, 5

53
Q

What is adaptation

A

a change in sensitivity (and nerve
impulse generation) in the presence of a constant stimulus.

54
Q

What is the difference between phasic receptors and tonic receptors

A

Phasic receptors are fast adapting, often giving bursts of impulses at the beginning and the end of the stimulus

Tonic receptors provide a sustained response with little or no adaptation.

55
Q

What is sensory acuity

A

refers to how accurately a stimulus can be located.

ANP1106 (11 decks)

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