Brainscape's Knowledge GenomeTM

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


See full index

MSK > Skin Physiology > Flashcards

Skin Physiology Flashcards

1
Q

What are the various ways that we can lose heat from the body?

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

What is normothermic heat transfer?

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

What is hypothermic heat transfer?

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

What is hyperthermic heat transfer?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  • When external temperature is < internal temperature, what will be the major mode of heat loss?
  • When external temperature is > internal temperature, what will be the major mode of heat loss?
A
  • Convective and radiative heat loss
  • Evaporative heat loss (sweat)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is thermoregulation?

A

Alteration of the rate of heat loss via physiological responses in the skin in order to maintain homeostasis and avoid excessive hyper or hypothermia.

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

What is the major regulator of body temperature?

A

Hypothalamus (integrator) –> effectors are components of the autonomic NS

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

What is the body’s physiologic, vascular response to being cold?

A

Vasoconstriction

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

What is the body’s physiologic and vascular response to being hot?

A

Vasodilation and sweating

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

The […] nervous system controls both the skin vasculature and the sweat glands.

A

Sympathetic –> causes both vasoconstriction and vasodilation

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

Under high body temperatures (e.g. during exercise), sympathetic centers are […] leading to vasodilation of cutaneous vasculature and heat dissipation.

A

inhibited

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

Under low body temperatures (e.g. hypothermia), sympathetic […] of alpha-1 receptors leads to vasoconstriction of cutaneous vasculature and heat conservation by moving blood away from the surface to conserve heat in the body’s core.

A

Stimulation

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

How does sweating lead to cooling of core body temp?

A

Sweating leads to evaporative cooling. Water molecules with greatest energy evaporate thereby lowering the average kinetic energy of the water and leading to lower temperature.

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

What is another name for sweat glands?

What are the 2 components of their structure?

A

Eccrine

Contain a secretory coil and a straight duct

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

Eccrine glands are composed of what 3 cell types?

A

Clear cells

Dark cells

Myoepithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q
  • Describe the affect of Ach on sweat glands
  • Is sweat that is secreted hypertonic, hypotonic, or isotonic under normal conditions?
A
  • Autonomic stimulation via acetylcholine (ACh) stimulates the eccrine glands to form an isotonic solution in the gland lumen.
  • Due to the active resorption of electrolytes by the sweat gland, sweat secreted by eccrine glands is a hypotonic solution
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Apocrine Sweat Glands

  • What are they?
  • When do they become active?
  • Where are they found?
  • What causes this sweat to have an odor?
A
  • Glands that secrete a milky viscous fluid into the infundibular portion of the hair follicle
  • Inactive until puberty
  • Axillae, areola, perianal region, external genitalia
  • Apocrine sweat is initially odorless, and gains malodor with breakdown by bacteria
18
Q
  • What is a sebaceous gland?
  • Where are they found?
A
  • Sebaceous glands are holocrine glands in the skin that secrete sebum to lubricate and waterproof the skin
  • Face, scalp, all skin areas except palms of hands and soles of feet
19
Q
  • What are the most common microorganisms found on the skin’s surface?
  • What causes the skin flora to vary across the various parts of the body?
A
  • Staphylococcus epidermidis, Staphylococcus aureus, Micrococci luteus, Diphtheroids (bacteria belonging to the genus Corynebacterium)
  • According to the nature of secretions, normal clothing worn, and immediacy to mucus membranes
20
Q

What 2 hormones are responsible for sympathetic vasoconstriction in hypothermia?

A

Neuropeptide Y

Norepinephrine

21
Q

How does the sympathetic NS achieve both vasoconstriction and vasodilation?

A

It has separate parallel nerves that innervate the vasculature to send each signal separately in response to the appropriate stimuli

22
Q

Post-ganglionic sympathetic vasodilator nerves are […] and respond to […] and […]

A

cholinergic

Ach; vasoactive intestinal peptide (VIP)

23
Q

How does humidity affect the effectiveness of sweating?

A

Increased mositure in air makes it less favorable to excrete more moisture onto the skin surface

24
Q

What type of gland is shown?

A

Eccrine gland

25
Q

Sebaceous Glands

  • Where are they found?
  • What are the 4 structures of the gland?
  • Where is the highest density of these glands?
A
  • Usually found in association with hair follicles in most areas of the body surface except for the palms and soles
  • They form the pilosebaceous units comprising four structures: the hair follicle, hair shaft, arrector pili muscle, and sebaceous gland
  • The highest density of sebaceous glands is found on the face
26
Q

Proliferation, differentiation, and metabolism of sebaceous glands are regulated by sex hormones, particularly […]

A

androgens

27
Q

[…] are the major cells within sebaceous glands that produce and accumulate lipids.

A

Sebocytes

28
Q

Sebocytes secrete their oily and waxy sebum via holocrine secretion. What is holocrine secretion?

A

In this process, the entire cell produces and becomes filled with the fatty product while it simultaneously undergoes programmed cell death (apoptosis)

29
Q

What is sebum made of?

Is this composition the same for everyone?

A
  • Sebum represents a complex oily mixture that consists of triglycerides, diglycerides, and free fatty acids, wax esters; squalene; cholesterol; and cholesterol esters.
  • Due to its complex composition, human sebum is remarkably specific due to individual genetic variations in enzyme concentrations, pH, and temperature
30
Q
  • Where does thermoregulatory sweat occur? How is this sweat controlled?
  • Where does emotional sweat occur? How is this sweat controlled?
A
  • This thermoregulatory sweating first occurs on the forehead and scalp, extends to the face and to the rest of the body, and occurs last on the palms and soles. Control of thermoregulatory sweating is cholinergic.
  • Under conditions of emotional stress, however, the palms, soles, and axillae are the first surfaces to sweat. Emotional sweating may be stimulated by adrenergic portions of the sympathetic division of the autonomic nervous system.
31
Q

Where in the eccrine sweat gland are ions resorbed?

A

The resorptive duct

32
Q

Describe the changes in ion concetration that are occuring inside an eccrine sweat gland to produce sweat.

A
33
Q

Why is sweat hypertonic in patients with Cystic Fibrosis?

A

They have a mutation in CFTR receptor which disrupts ability to resorb Cl- from sweat and by association also Na+

34
Q

How do your eccrine glands adapt to sustained higher temps?

A

You sweat more but it is less salty. Adaptations mostly through Aldosterone acting on the duct portion of sweat gland and addition of more Na+ channels and Na+/K+ pumps

35
Q

What region of the DNA is particularly susceptible to damage from UVB radiation?

A

Telomeres (TTAGGG –> thymine dimers)

36
Q

What is happening to your skin when you have a sunburn?

A

Inflammation caused by release of cytokines by keratinocytes or mast cells. This inflammation causes erythema due to vessel dilation.

37
Q

What is shown by the yellow arrows?

A

Sunburnt cells in the epidermis

38
Q
  • What signaling pathway is activated when DNA is damaged from UV radiation?
  • What effect does this have on the skin?
A
  • p53
  • Tanning response –> p53 turns on transcription factors that are involved in melanogenesis –> produce more eumelanin –> stabilize melanosomes –> darken skin –> more protection against UVB
39
Q

Is sun really the best way to get vitamin D?

A

No - in order to activate 7DHcholesterol, UVB radiation must be at specific wavelength of light (290-300nm). Depending on where you live (latitude), the radiation from the sun may not reach this wavelength year round (in CT it is only during June - August). As such, sun exposure outside these months is unlikely to produce active vitamin D so most people need supplementation if their diet is inadequate.

40
Q

What is the effect of skin color and vitamin D synthesis?

A

Lighter skin (types 2 and 3) are able to produce more active vitamin D3 compared to darker skin tones (4 and 5) –> people with darker skin are more likely to be vitD deficient

MSK (38 decks)

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