Brainscape's Knowledge GenomeTM

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


See full index

03 - Body Logistics > 17 - Skin > Flashcards

17 - Skin Flashcards

1
Q

What are the functions of the skin?

A
  • Prevent water loss
  • Prevent ingress of pathogens
  • Sensation
  • Lubrication
  • Secretion (e.g pheromones, urea)
  • Absorption (as avascular)
  • Thermoregulation
  • Vitamin D synthesis
  • Protection and repair (melanin, fibroblasts, abrasion)
  • Storage of energy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the three layers of the skin and what are the layers within these layers called?

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

What else can the hypodermis be called?

A

Subcutaneous layer

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

What are the two layers of the dermis?

A
  • Papillary (upper)
  • Reticular (lower)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the structure, location and function of the hypodermis?

A

Location: Lowest layer

Structure: Adipose tissue, loose CT with macrophages, fibroblasts etc. Vascular and nerve bundles

Function: Insulate, shock absorber, energy store for below muscles, connect skin to underlying bone and tissue, make hormones e.g leptin

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

What does the thickness of the hypodermis tell us?

A
  • Thick if well fed as lots of fat
  • Gets thinner with age
  • Very thick on feet (shock aborb) and palms (grip)
  • Men have thickest in abdomen and shoulders
  • Female have thickest in thighs, buttocks, hips
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the issue with having a thinner hypodermis as you get older?

A
  • Lose ability to thermoregulate as less fat
  • Leads to wrinkling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are other words for the epidermis?

A

Corium and cutis

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

What is dermal papillae?

A

Interdigitations of epidermis and dermis, holds the epidermis and prevents the whole layer being lost.

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

What is the stucture and function of the dermis?

A

Structure: Dense irregular CT. Varying thickness, thicker hands and fit. Collagen and elastin. Papillary and reticular regions

Function: Sensation (mechanoreceptors), hold shape of skin, thermoregulation (hairs and sweat glands)

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

What leads to wrinkling?

A
  • Thinner hypodermis
  • Thinner dermis due to less collagen and elastin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the structure of the epidermis?

A
  • Held together by adherens junctions
  • Avascular

Can Leah Give Shri Babies

Horny, Granular, Prickle Cell, Basal

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

What is the function of the epidermis in general?

A
  • Prevent water loss
  • Prevent pathogen ingress
  • Keratin synthesis
  • Prevent tissue loss by abrasion
  • Present pathogens to immune cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the structure and function of the stratum corneum?

A
  • Horny cell layer
  • Dead squames of keratinocytes
  • Thickest on palms and soles of feet
  • Keratin shed when abrasion
  • Prevent waterloss and pathogen ingress
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the structure and function of the stratum lucidium?

A
  • Thin clear layer only found in palms and soles of feet
  • Flat cells with keratin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the structure and function of the stratum granulosum? (granular layer)

A
  • Stratified squamous
  • Lamellar granules that make tonofibrils and secrete them
  • Tonofibrils (keratin filaments and keratinohyalin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the structure and function of the stratum spinosum?

A
  • Cuboidal (3 layers min held by desmosomes)
  • Produce lamellar bodies and first golgi
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the structure and function of the stratum basale?

A
  • Columnar cells constantly dividing keraitnocytes
  • Appositional growth, move away from basal layer as they differentiate
  • Home to melanocytes
  • Produce tonofilaments
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Label the parts of the epidermis.

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

What is the keratin synthesis pathway?

A
  1. Tonofilaments made in the s.basal
  2. Lamellar bodies produced in s.spinosum
  3. In granulosum, lamellar bodies combine keratohyalin granules and tonofilaments to form tonofibrils (keratin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What happens once keratin has formed in s.granulosum?

A
  • Secreted and acts as a waterbarrier
  • Desmosomes broken down so keratin can be shed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is psoriasis?

A

Condition characterised by silvery scaly skin, due to the transit time of keratinocytes being 2-3 days rather than 28-40 days. Skin doesnt have time to produce keratin

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

What is hyperkeratosis?

A

Too much keratin build up, especially hands and feet.

Due to cells not undergoing apoptosis so continue to lay down keratin or due to desmosomes not being broken down

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

What are the main cells in the epidermis?

A
  • Langerhan’s
  • Melanocytes
  • Keratinocytes
25
Q

What is the stucture, function and location of melanocytes?

A
  • 1 in 8 cells
  • In basal layer
  • Dendrocytes from melanocyte are phagocytosed by keritanocyte and transfer melanin
  • Same number of melanocytes in everyone, dark people just produce larger melanosomes that go up to s.granulosum. White people only up to spinosum
26
Q

What do langerhan cells do?

A
  • Dendritic cells mainly in s.spinosum.
  • Macrophage and then present antigens to lymphocytes to stimulate immune response
  • Respond to pathogens entering through skin
27
Q

What do Merkel cells do?

A

Mechanoreceptor associated with nerve endings.

Dark skin have more receptors

28
Q

What skin issue do people from Africa have living in England?

A

Vitamin D deficiency due to lack of sunlight, therefore eczema

29
Q

What are the two types of skin and the exceptions?

A
  • Thin hairy
  • Thick non-hairy

Exceptions: Back of ears, lips and external genitalia

30
Q

Where is non-hairy thick skin and what is it’s structure?

A
  • Palms and feet
  • Between fingers and toes

Structure:

  • No hair
  • No arrector pili muscles or sebaceous glands
  • Thicker s.corneum
  • Thinner dermis
  • Increased density of mechanoreceptors
31
Q

What is the function of thick skin?

A
  • Increased sensation
  • Prevent tissue loss to abrasion
  • Increase friction between skin and surface to prevent slip
32
Q

What are the main features of the thin skin?

A
  • Sebaceous glands
  • Eccrine sweat glands
  • Arrector pili muscle
  • Hair follicle
33
Q

What are the main differences between thin and thick skin histologically?

A
34
Q

What are the main skin appendages?

A
  • Hair
  • Arrector pili
  • Sebaceous glands
  • Sweat glands
  • Nails
35
Q

What are the three main types of hair?

A

- Lanugo: covers developing fetus

- Vellus: short, thin, light coloured. Not connected to sebaceous gland

- Terminal: (head, scalp, eyebrows, axilla): Long, wide, dark coloured. Produced due to testosterone

36
Q

What are the functions of the hair?

A
  • Thermoregulation (+ uv protection)

- Sexual attraction (pheromones)

- Sensation

(nerve endings in bulb can feel air movement)
- Protection

(stop dust, pathogens, light, sweat entering and move sweat away from armpit)

37
Q

What is the general function of the arrector pili muscle?

A
  • Smooth muscle
  • Origin (papillary dermis) Insertion (hair bulb)
  • Causes hair to stand up when contract
  • Can induce sebum release as when contract can squeeze gland (makes slippy) (sympathetic response)
38
Q

What are the structure and functions of nails?

A

Structure:

  • Alpha helix keratin
  • Three layers: Nail plate –> Nail matrix –> Nail Bed

Function:

  • Enhance sensitivity of nail tip
  • Extended precision grip (splinter)
  • Protection of distal phalanx and surrounding soft tissues from injury
  • Precise movement of digits through counter pressure exerted on pulp
39
Q

What are all the types of mechanoreceptors and what do they detect?

A

- Krause End Bulb: thermoreceptor

- Nociceptor (end of free nerve in epidermis): pain

- Tactile disc (Merkel in non-hairy and meissener in hairy): attach to basal layer of keratinocytes. touch and pressure

  • Meissener: Tapping and flickering movements

- Pacinian Corpuscle: Vibration

- Rufini’s Corpuscle: Tissue stretch and joint movement

- Root Hair Plexus: Vibrations in hair shaft

40
Q

What is the pilosebaceous unit?

A

Sebaceous gland, hair, hair follicle, and arrector pili muscle

41
Q

What is a sebaceous gland?

A

Acinar exocrine

Produces waxy/oily substance, called sebum, to lubricate skin or hair.

Doesn’t smell but when bacteria break it down it smells

42
Q

What does sebum in the pilosebaceous unit consist of?

A
  • Lipids, wax, fat and dead fat producing cells (holocrine)
43
Q

What do sebaceous glands do when there is no hair shaft to travel up?

A
  • They attach to an apocrine sweat gland, e.g in the vagina
  • Not found on palms and soles of feet
44
Q

What is a type of specialised sebaceous gland?

A

Meibomian glands in upper eyelid. Secrete meibum onto eye to stop drying of tears

45
Q

What issues can sebum cause?

A
  • Oily skin
  • Acne
  • Pimples (keratin and sebum form hyperkeratonic plug called microcomedo which blocks pores)
46
Q

What is the structure of a sweat gland?

A
  • Convolute tubule exocrine

Eccrine: All over body, mostly in palms, head and feet. For cooling, water based secretions constantly

Apocrine: Axilla and perianal areas. Secrete periodically mixed with sebum from sebaceous glands. Merocrine secretion that is odorless. Water, protein and carbohydrate.

47
Q

What is hyperhidrosis?

A

Sweat glands (particularly eccrine) overreact to stimuli producing more sweat than normal

48
Q

What is alopecia totalis and alopecia universalis?

A

Totalis - All hair on head lost

Universalis - All hair on body lost

49
Q

What are the signs of psoriasis, why is it caused and what triggers it?

A
  • Chronic Autoimmune Disease
  • Hereditary
50
Q

What is malignant melanoma, what are the signs, where is it found and who is at risk?

A
51
Q

What are the two types of malignant melanoma and what are some of the characteristics?

A
52
Q

What are the signs of vitaligo and where is it found on the body?

A
53
Q

What are the two types of vitaligo and why do they occur and who do they affect?

A
54
Q

What are they symptoms of alopeia areata, who is likely to be affected and what is the mechanism of the disease?

A
55
Q

What is toxic epidermal necrolysis?

A

Severe reaction to drugs. Full thickness epidermis damage. It is life threatening and has high mortality.

Need to give them fluids and cool them down. (think about functions of skin when treating someone with massive skin issue)

56
Q

What are they key things to do when doing a dermatology examination?

A
  • Good lighting
  • Examine scalp, nails, mucous membranes
  • Palpate
  • Examine other systems, e.g lymph nodes
  • Ask about family and drug history
57
Q

What are the symptoms of eczema?

A
  • Dry skin
  • Bilateral
  • Transient
  • Weather makes it worse and allergies
  • Itchy
  • Red inflammed
  • Hypersensitivity
58
Q

What is the issue if you are diagnosed with one autoimmune disease, such as psoriasis?

A

Can be linked to other autoimmune diseases such as rheumatoid arthritis

59
Q

Why does cystic fibrosis lead to hyperhidrosis?

A

CTFR gene is mutated so the chloride transport is defective. Chloride cannot be transported out of the cell so neither can water. There is a build up of water in the sweat gland cells so more sweat produced and secreted

03 - Body Logistics (20 decks)

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