Lesson 4: The Integumentary System Flashcards
1
Q
Epidermis
A
- The outermost and thinnest layer of the skin
- Epi indicates on or over the dermis
- Composed of 5 distinct strata
- Most superficial skin layer
2
Q
Dermis
A
- Deeper and thicker than the epidermis; its the innermost layer of the skin
- Dermis is deep
3
Q
Subcutaneous Tissue or Hypodermis
A
- Layer of fat and connective tissue underneath the epidermis and dermis
4
Q
Functions of Subcutaneous Tissue or Hypodermis
A
- Fat (adipose) tissue in this layer provides insulation and shock absorption
- It serves as a store of energy that can be metabolized should the need arise
5
Q
Stratum Germinativum
A
- Innermost layer of the epidermis
- This is the layer in which new skin cells are produced
- New skin cells “germinate”
6
Q
Keratin
A
- As new cells are produced, they are pushed upward toward the surface of the skin. As they do so, they die, and the cytoplasm of those cells is replaced with this protein
- This keratinized layer of outermost skin is what gives us that tough, flexible, and waterproof protection from the outside world
- Substance that makes up our hair, nails, as well as horns and tusks of other animals
7
Q
Stratum Corneum
A
- The uppermost layer of keratinized skin cells
- Cells of this layer eventually flake off, being replaced by younger cells travelling upward from underneath
- 70-80% of house dust is composed of dead skin
- Think of a bad sunburn, these cells come off in thin sheets refer to as colloquially as peeling
8
Q
Melanocytes
A
- Your skin has a colour and the colour reflects hereditiary factors that influence the amount of a brown pigment (melanin) produced by specialized cells
- More or less have the same number of Melanocytes
- Darker our skin gets is a function of the activity of our melanocytes (the more active melanocytes are the darker skin you have)
- Activity of melanocytes can also be affected by exposure to the sun, more exposure to sun stimulates melanocytes to produce more melanin which increases the darkness of the skin
9
Q
Skin under the Nails
A
- No matter your skin colour overall, the skin under your nails at best is lightly pigmented
- Tells us about the availability of oxygenated blood
- Poorly oxygenated blood or low blood volume can reveal itself through a discolouration of the skin specifically blue-grey appearance of nail beds
10
Q
Cyanotic
A
- Someone with grey- blue nail beds, lips etc..
11
Q
Cyanosis
A
- People with light skin colouration can take on this overall pallor but its observable in the nails regardless of the levels of pigmentation on the back of the hand
12
Q
Vitiligo
A
- Results from a reduction in skin pigmentation that follows the loss of melanocytes
- Most often due to genetic factors
- Degree of pigmentation varies across bodies and can be influenced by other factors
- Pregnant women often experience hormone-related changes in skin colour, increased pigmentation of the areolas
- People with freckles are also familiar with another source of variation in skin colouration, determined by genetic traits. Freckles are a kind of skin lesion
13
Q
Skin Lesions
A
- Involve some variation from the normal structure of tissue
- Often noted by abnormal tissue density or colouration
- Not necessarily a sign of disease
14
Q
Chloracne
A
- Condition characterized by the papules, firm, raised lesions of less than one centimetre in diameter
15
Q
Warts
A
- Another form of this type of skin lesion
- Papules can be found in infectious diseases such as molluscum contagiosum and chicken pox, and non-infectious causes such as eczema and allergic reactions
16
Q
Plaques
A
- Large, raised lesions that are > 1cm in diameter
- While Plaque psoriasis is the most common example of this lesion, plaques can also result from skin infections like ring worm and from the yeast infection tinea
- Plaques can also be found in cases of eczema
17
Q
Plaque psoriasis
A
- Is a condition characterized by abnormally rapid growth of skin that becomes raised and red-silver in appearance
- It can flake off, and be itchy
18
Q
Vesicles
A
- Characterized by small <1cm fluid filled blisters
- Caused by the same virus that gives us chickenpox
- Herpes viruses and Shingles cause similar lesions
- Caused by the build-up of fluid under the epidermis
- Some cases you can find vesicles in eczema and allergic reactions such as poison ivy
19
Q
Pustules
A
- Elevated lesion that is filled with pus such as acne vulgaris
- Specifically observed in the disease smallpox which now has a vaccination
- Can result from allergic reactions and bites of insects
20
Q
Crust
A
- Skin lesion that makes you very itchy
- Referred to as a scab
- Its a raised area with dry blood or exudate (fluid that leaks out of blood vessels)
21
Q
Wheals or Urticaria
A
- Elevated skin lesions commonly called a hive
- It’s a firm, raised area of skin with an irregular shape and a light- coloured centre
- Commonly caused by allergic reactions to food, medications, or insect bites
- Urticaria pigmentosa
22
Q
Macules
A
- Freckles are an example
- Small, flat, discoloured areas of skin
- Some moles are macules and small areas of vitiligo are considered macules as well
- Flat lesion that is small <1cm skin lesions that are different in colour in comparison to surrounding skin
23
Q
Patches
A
- Flat lesion
- Large >1cm macule as you’d find in a more extensive case of vitiligo
- They can be caused by injury, illness and inflammation
24
Q
Excoriations
A
- Depressed lesions
- Usually called scratches
- When we have a scratch the epidermis is missing which exposes the underlying dermis
25
Q
Atrophies
A
- Depressed skin lesions caused by the loss of epidermal tissue, leading to a depressed appearance on the surface of the skin
- Can result from aging, excessive exposure to sunlight and overuse of topical steroids
- Stretch marks that some women get when they are pregnant is a form of atrophy
26
Q
Ulcers
A
- Pressure sores, such as bedsores are an example
- Crater-like in appearance, caused by the loss of skin in the epidermis and sometimes dermis
- Can also get them in your mouth in the form of canker sores
27
Q
Fissures
A
- Involves a linear crack in the epidermis that extends to the dermis
- Can happen due to overly dry skin, skin sensitivities or from fungal infections like athlete’s foot
- Skin lesions involving deep cracks to the epidermis
- One cause of skin fissures in children is called juvenile plantar dermatosis
28
Q
Lanugo
A
- Baby hair
- Falls our shortly after birth
29
Q
Hair Papilla
A
- All hair originates here
- Rooted in the dermis and fed by dermal blood vessels
30
Q
Hair Follicle
A
- Hair grows from the papilla, through a tube-like structure that runs toward the surface of skin
- Hair root is at the base of the hair follicle, becoming visible where it emerges from the epidermis
31
Q
Arrector Pilli
A
- Small, involuntary muscles
- Allows hair to stand erect when we are frightened or cold
- Also what causes goosebumps
32
Q
Alopecia
A
- Loss of hair, regardless of its cause
33
Q
Nail Body
A
- Refer to as nail
- Made up of keratin, the same protein of which hair and the stratum corneum are composed
- Nail body begins at the nail root (the cuticle is superficial to the root), extends passed the lunula, overlays the nail bed (the part that turns grey-blue if were cyanotic) and terminates at the free edge- the part that you trim or file
34
Q
Nails
A
- Not all nails are the same
- Lunulas vary in size, and can be entirely absent on some nails while they tend to be the biggest on thumb nails
- Nail beds are always lightly pigmented, but varies by skin colour
- Ridges running the length of the nail are quite common and tend to become more pronounced with age
- If you have white marks in your nails, its most likely due to trauma to the nail body not a nutritional deficiency
35
Q
Meissner corpuscle
A
- Also called tactile corpuscle
- Receptor that allows us to detects light touch
36
Q
Lamellar corpuscles
A
- Also called Pacini corpuscle
- Receptor located in the dermis and it lets us sense pressure
37
Q
Skin Glands
A
- Play important roles in facilitating temperature regulation and protection
38
Q
Two Key Functions of Integument
A
- Temperature regulation
- Protection
39
Q
Sweat Glands
A
- Critical to temperature regulation
40
Q
Sebaceous Glands
A
- Contribute to our protection from the outside world
41
Q
Eccrine Sweat Glands
A
- Can be found all over the body
- They produce what we normally think of as sweat or perspiration which is excreted through our pores
42
Q
Apocrine Sweat Glands
A
- Concentrated in the axilla (armpits) and around the genitals
- Source of smelly sweat
- The decomposition of secretions from apocrine glands that cause body odour
43
Q
Sebum
A
- Sebacesous glands produce an oily secretion
- Lubricates and moisturizes the surface of the skin
- Can clog pores contributing to acne
- The pores involved with acne vulgaris becomes pustules hence their white centres
- Blackheads are simply deposits of sebum that have blocked a pore and their dark appearance is due to oxidation of the sebum (it is not dirt in your pores)
44
Q
Impetigo
A
- Kids get this
- Its really contagious
- Its caused by staph or strep bacteria
- Starts out red and if unchecked is characterized by vesicles and really nasty looking yellowish crusts
45
Q
Tinea
A
- Generic name for a number of mycoses or skin disorders, including ringworm, athletes foot, jock itch, fungus
46
Q
Warts
A
- Caused by a papilloma virus, creating a papule on the surface of the skin
- They’re passed via skin to skin contact
- Usually they’re bening, but some can become cancerous as in cervical cancer for instance
47
Q
Furuncles
A
- They’re caused by staph infections of hair follicles
- Generally called boils
- When there’s a number of them that coalesce into a single, large lesion they are called carbuncles
48
Q
Scabies
A
- Skin disorder caused by a mite that burrows into the skin to lay eggs
- The hatchings cause a hypersensitivity reaction that causes the formation of papules and can lead to intense itching
- It can be spread by skin to skin contact including sexual activity
49
Q
Decubitus Ulcers
A
- These are called bedsores or pressure sores
- Due to a lack of blood flow the affected tissues
- Often occur in people who are bedridden and unable to move without assistance
50
Q
Scleroderma
A
- Means hard skin
- Is an autoimmune disease that caused hardening (that is loss of flexibility) of the skin
51
Q
Psoriasis
A
- Skin condition causes a red-silver- white and scaly plaque due to overgrowth of the skin
52
Q
Eczema
A
- Common inflammatory condition of the skin involving crusts, vesicles and papules
- Isn’t a health condition itself but rather is indicative of some underlying concern such as an allergic reaction
53
Q
Squamous Cell Carcinoma
A
- The most common form of skin cancer
- Results in hard, raised but usually painless nodules in the epidermis
- It can metastasize, affecting other organs
- Slow-growing form of cancer
54
Q
Basal Cell Carcinoma
A
- Skin cancer which begins as papules that eventually erode into bleeding crusts, form at the base of the epidermis
- It is less likely to metastasize than other skin cancers
- Usually fond on the upper face
55
Q
Melanoma
A
- Gets the most attention
- It is the deadliest form of skin cancer because it readily metastasizes, so early detection and removal are critical to survival
- Cancer of melanocytes so it commonly orginates in a densely-pigmented nevus
56
Q
Kaposi’s Sarcoma
A
- Form of skin cancer is caused by a herpes virus and has become associated with HIV-AIDS due to its incidence in the immunocompromised
- It forms as purple- coloured papules and readily spreads to lymph nodes and internal organs
