The Integumentary System Flashcards
Dermatology
the study of skin
What is the epidermis?
- made up of keratinised stratified squamous epithelium
- tough, waterproof outer layer that’s continuously worn away
What is the dermis?
- made up of areolar and adipose connective tissue containing collagen and elastic fibres
- lies beneath the epidermis which is thicker and contains the nerves, blood vessels, sweat glands and hair roots
What are the 5 layers of the epidermis (bottom to top)?
- Stratum basale (basal cell layer)
- Stratum spinosum (prickle cell layer)
- Stratum granulosum (granular cell layer)
- Stratum lucidum (clear cell layer)
- Stratum corneum (horny-cell layer)
What are melanocytes?
produce a pigment called melanin, that contributes to skin colour and absorbs UVR from the sun
What is the process of desquamation?
the skin cells are constantly shed
What are the (2) layers of the dermis?
- Superficial papillary layer
- Reticular layer
What are the (7) functions of the skin?
- Sensation - cutaneous sensory receptors sensitive to touch, temperature, pressure + pain
- Absorption
- Protection - against trauma, bacteria, dehydration, UVR radiation, chemical + thermal damage
- Heat regulation - cools the body through sweating + vasodilation; heats through vasoconstriction, contraction of erector pili muscles, shivering
- Excretion - excretes waste
- Secretion - secretes sebum, helps keep skin supple + waterproof
- Vitamin D synthesis - helps regulate calcium levels necessary for growth + bone strength
What are the (3) types of hair?
- Lanugo
- Vellus
- Terminal
What is lanugo hair like?
soft hair found on a foetus
What is vellus hair like?
soft hair all over the body (except palms, soles, eyelids, lips + nipples)
What is terminal hair like?
log, coarse hair found on the head, eyebrows, eyelashes, armpits + pubic areas
Describe the structure of hair.
- has columns of keratinised dead cells
- grows out of the hair follicles
- made up of shaft (superficial end) and root which penetrates the dermis
- arrector pili muscles pull the hair up to vertical position as a response to cold, fight or differing emotions (goosebumps)
What are red flags on skin problems?
1.any rash accompanied by fever, nausea and headache
2. widespread and generalised erythema (reddening)
3. widespread and generalised pruritus (itching)
4. signs of painful and rapidly worsening infections and blistering
5. severe sunburn
6. severe jaundice (yellowing)
7. moles that are changing, itching and bleeding
What are some skin disorders?
- Acrochordon (skin tags)
- Alopecia
- Keloids
- Psoriasis
- Seborrheic keratoses (senile warts)
- Xanthoma
- Dermatitis
- Eczema
- Urticaria (nettle rash or hives)
- Carbuncles
- Cellulitis
- Conjunctivitis
- Folliculitis
- Furuncles (boils)
- Hordeolum (stye)
- Impetigo
- Burns
- Cancers – squamous cell carcinoma (e.g., prickle-cell cancer), basal cell carcinoma (e.g., rodent ulcers), and melanoma.
