Brainscape's Knowledge GenomeTM

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


See full index

Biol 235 Chapter 16 > 16.2 > Flashcards

16.2 Flashcards

1
Q

What are somatic sensations?

A

Arise from stimulation of sensory receptors embedded in the skin or subcutaneous layer

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

Where are somatic sensations found?

A

In mucous membranes of the mouth, vagina and Anus & in skeletal muscles, tendons and joints

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

Which areas in the body have the highest density of somatic sensory receptors?

A

Tip of tongue, lips and fingertips

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

What are the 4 modalities of somatic sensation?

A
  1. Tactile
  2. Thermal
  3. Pain
  4. Proprioceptive
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are tactile sensations?

A

Include touch, pressure, vibration, itch, tickle
(Touch)

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

There are 2 types of rapidly adapting touch receptors. What are corpuscles of touch (or Meissner corpuscles)

A

Touch receptors that are located in the dermal papillae of hairless skin.
Each corpuscle is an egg shaped mass of dendrites enclosed by a capsule of connective tissue.

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

What are the sensations of corpuscles of touch receptors? Rapid or slow adapting receptors?

A

Onset of touch and low frequency vibrations
Rapid

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

Where are corpuscles of touch abundant in the body?

A

Fingertips, hands, eyelids, tip of tongue, lips, nipples, soles, clitoris, tip of penis

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

2nd type of touch receptors is hair root plexuses. Where are they found and the structure?

A

Hairy skin.
Consist of free nerve endings wrapped around hair follicles
Detect movements on the skin that disturb hairs

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

2 types of slowly adapting touch receptors what are they

A

Type 1 cutaneous mechanoreceptors (tactile(merkel) discs)
Type II cutaneous mechanoreceptors ;Ruffini corpuscles

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

What is the structure of tactile (merkel) discs ?

A

Saucer shaped, flattened free nerve endings that make contact with tactile epithelial cells (merkel cells) on the stratum basale

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

Plentiful in fingertips, hands, lips, external genitalia?

A

Type 1 cutaneous mechanoreceptors

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

Elongated encapsulated receptors located in the dermis, subcutaneous layer and other tissues of the body. Highly sensitive to skin stretching (such as a massage)

A

Type II cutaneous mechanoreceptors (or Ruffini corpuscles)

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

A sustained sensation that is felt over a larger area than touch, occurs with deeper deformation of the skin and subcutaneous layer?

A

Pressure

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

Which type of receptor consist inure to sensations of pressure?

A

Type I and II mechanoreceptors
Able to respond to steady pressure stimulus because they are slowly adapting

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

Where do sensations of vibration result from?

A

Rapidly repetitive sensory signals from tactile receptors

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

What are the receptors for vibration?

A

Lamellated corpuscles and corpuscles of touch

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

What consists of a nerve ending surrounded by a multilayered connective tissue that resembles a sliced onion?

A

Lamellated corpuscle (or pacinian corpuscle)

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

Where are Lamellated corpuscles found?

A

In the dermis, subq layer and other body tissues

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

Lamellated corpuscles respond to high or low frequency vibrations?

A

High

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

Corpuscles of touch respond to high or low frequency vibrations

A

Low

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

What does itch sensation result from?

A

Stimulation of free nerve endings by certain chemicals, such as bradykinin (a kindin a potent vasodilator), histamine, or antigens in mosquito saliva injected from a bite

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

Scratching usually alleviates itching by?

A

Activating a pathway that blocks transmission of the itch signal through the spinal cord

24
Q

What are free nerve endings that have receptive fields about 1 mm in diameter on the skin surface?

A

Thermoreceptors

25
Q

Cold receptors (one of the 2 distinct thermal sensations) are located where? And attached to what fibers?

A

Located in the stratum basale of the epidermis
Attached to medium diameter myelinated A fibers although a few connect to small diameter unmyelinated C fibers

26
Q

Where are warm receptors located

A

In the dermis and are attached to small diameter unmyelinated C fibers

27
Q

Cold receptors (activated temp between 10 and 35)
Warm receptors (temp between 30 and 45)
What about temps below 10 and above 45? What receptors are stimulated?

A

Pain receptors

28
Q

What are nociceptors?

A

The receptors for pain
Are free nerve endings found in every tissue except the brain

29
Q

What are the 2 types of pain?

A

Fast and slow

30
Q

Fast pain occurs rapidly usually within 0.1 second after stimulus applies. Because of how the nerve impulses propagate along which fibers?

A

Medium diameter myelinated A fibers

31
Q

Slow pain begins after a second or more after stimulus and gradually increases in intensity. Impulses for slow pain conduct along which fibers?

A

Small diameter unmyelinated C fibers

32
Q

Pain that arises from stimulation of receptors in the skin is called ?

A

Superficial somatic pain

33
Q

Stimulation of receptors in skeletal muscles, joints, tendons & fascia causes what type of pain?

A

Deep somatic pain

34
Q

Visceral pain?

A

Results from stimulation of nociceptors of visceral organs

35
Q

Referred pain?

A

In instances of visceral pain, the pain is felt in or just deep to the skin that overlies the stimulated organ or in a surface area far from the stimulated organ

36
Q

What allows us to recognize that parts of our body belong to us and allow us to know where our head and limbs are located and how they move

A

Proprioceptive sensation (or proprioception)

37
Q

Kinesthesia

A

Perception of body movement

38
Q

Proprioceptors also allow weight discrimination which is?

A

The ability to assess the weight of an object

39
Q

3 types of Proprioceptors?

A

Muscle spindles
Tendon organs
Joint kinesthetic receptors

40
Q

What are muscle spindles ?

A

Proprioceptors that monitor changes in the length of skeletal muscles and participate in stretch reflexes

41
Q

How does a muscle spindle respond to stretching a skeletal muscle not to vigoursly ?

A

Muscle tone
Brain sets an overall level of muscle tone
Which is the small degree of contraction present while muscle at rest

42
Q

Each muscle spindle consists of several slowly adapting nerve endings that wrap around 3-10 specialized muscle fibers. What are these called?

A

Intrafusal fibers

43
Q

In muscles that produced finely controlled movements (such as fingers or eyes) are muscle spindles plentiful or fewer?

A

Plentiful

44
Q

The only skeletal muscle that lacks spindles?

A

Tiny muscles of ear

45
Q

What is the main function of muscle spindles?

A

To measure muscle length - how much a muscle is being stretched

46
Q

Sudden or prolonged stretching of central areas of the inteafusal muscle stimulates what?

A

Sensory nerve endings
The resulting nerve impulses propagate into the CNS
Information from muscle spindles arrives quickly at the somatic sensory areas of cerebral cortex which allows conscious perceptions of limb positions and movements
At the same time impulses from muscle spindle pass to cerebellum where input is used to coordinate muscle contractions

47
Q

Near the middle of intrafusal fibers muscle spindles contain motor neurons called?

A

Gamma motor neurons

48
Q

What do these gamma motor neurons do?

A

Terminate near both ends of the intrafusal fibers and adjust the tension in a muscle spindle to variations in the length of the muscle

49
Q

Surronding muscle sound also are ordinary skeletal muscle fibers called?

A

Extrafusal muscle fibers
Supplied by large diameter a fibers called alpha motor neurons

50
Q

Where are the cell bodies of gamma and alpha motor neurons located?

A

In the anterior gray horn of the spinal cord (or in the brain stem for muscles in the head)

51
Q

What are tendon organs?

A

Slowly adapting receptors located at the junction of a tendon and a muscle

52
Q

What do tendon organs do when tendon reflexes are initiated?

A

Protect tendons and their associated muscles from damage due to excessive tension

53
Q

Each tendon organ consists of?

A

A thin capsule of connective tissue that encloses a few tendon fascicles (bundles of collagen fibers)

54
Q

When tension is applied to a muscle, the tendon organs generate nerve impulses that propagate into the CNS providing info about changes in muscle tension. The resulting tendon reflex decrease muscle tension by causing?

A

Muscle relaxation

55
Q

Joint kinesthetic receptors present where?

A

Within and around the articulate capsules of synovial joints

Biol 235 Chapter 16 (5 decks)

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