Skin Flashcards
1
Q
Describe the functions of skin (6)
A
- physical barrier
- temperature regulation
- sensation and nerve signalling
- vitamin D synthesis
- immune defence
- protection against UV radiation
2
Q
Describe the basic layers of the skin
- Epidermis
- Dermis
- Hypodermis
A
- stratified squamous epithelium made up of ketatinocytes
- dense, irregular connective tissue supported by fibroblasts
- loose connective tissue with adipose cells; larger blood vessels and nerves
3
Q
- Moving deep to superficial, name the order of the layers of the epidermis
- what are tonofibrils? In which layer are they produced?
- What are keratohyalin granules? In which layer are they produced?
A
- stratum basale. stratum spinosum. stratum granulosum. (stratum lucidum). stratum corneum
- intracellular keratin fillaments which link adjacent cells via desmosomes. Found in the stratum spinosum
- granules that contain proteins which bind to and aggregate keratin fillaments. Found in the stratum granulosum.
4
Q
- What is the difference between thick skin and thin skin?
- where is the thickest skin found?
- Where is the thinnest skin found?
A
- thick skin has a well defined stratum corneum, and may contain a 5th layer, the stratum lucidum.
Thin skin has a less prominent stratum corneum, and contains hair and glands - soles and palms
- eyelids
5
Q
- what are the most abundant cells in the epidermis?
- What is the role of melanocytes?
- where are melanocytes found?
- What are langerhans cells?
- What are merkel cells?
- where are the Merkel cells found?
A
- ketatinocytes
- synthesize melanin which is packaged into melanosomes and transferred to neighbouring keratinocytes. This protects against UV damage
- they are found in deeper levels of the epidermis
- APCs of the epidermis
- specialised cells associated with nerve fibres, that are responsible for fine touch sensation
- basal layer
6
Q
- What is found in the papillary dermis?
- What is found in the reticular dermis?
- What is the hypodermis composed of?
- what is the function of the hypodermis?
A
- loose connective tissue made up of collagen and elastin fibres. Also contains extensive capillary networks, lymphatics and nerve endings
- dense connective tissue made up of thick bundles of collagen; fibroblasts and immune cells; vessels and nerves;
- mature adipose tissue
- insulator, protector, energy store
7
Q
- what is the nail plate?
- what is the nail matrix?
- what is the nail bed?
- what is a hair follicle?
- describe the 3 stages of hair growth
A
- hard keratinised plate at the distal end of each digit. Analogous to cornified layer
- tissue which the nail protects. Part of the nail bed beneath the nail that contains nerves, lymphatics and blood vessels. Produces the cells that become the nail plate
- skin beneath the nail plate. made of dermis and epidermis
- tubular structures formed from the basal layer of epidermis
- growth > transition > rest
8
Q
- what are sebeaceous glands?
- What type of secretion do sebeaceous glands carry out?
- what is the shape of sebaceous glands?
- what are eccrine sweat glands?
- what type of secretion do eccrine sweat glands carry out?
- where are eccrine sweat glands predominantly found?
- what are apocrine glands?
- what type of secretion do apocrine glands carry out?
A
- glands that secrete sebum (a lipid containing substance that coats and waterproofs hair)
- hollocrine secretion
- acinar
- coiled, tubular glands that secrete sweat.
- merocrine secretion
- throughout all tissues but particularly on soles, palms, forehead and axillae
- glands that secrete a viscous, cloudy secretion which contains pheromones and reacts with skin bacteria to cause body odor
- apocrine
9
Q
describe the process of wound healing
A
- haemostasis
- inflammation
- fibroplasia
- epithelialisation
- remodelling
10
Q
Define the following:
- Naevus
- Pruritis
- Wheals
- Erythema
- Purpura
- Petichiae
- Ecchymoses
- Vitelligo
- Desquamation
- Lichenification
- Macules
A
- localised malformation of tissue structure
- itching
- transient raised lesions due to oedema
- redness which blanches on pressure
- red or purple colour due to bleeding into the skin
- small pinpoint red lesions due to bleeding into the skin
- large, bruise like patches
- loss of skin melanocytes, causing depigmentation
- scaling, due to skin lifting off the surface
- thick, leathery patch of skin
- flat, distinct coloured areas of skin less than 1cm wide
11
Q
Name 4 clinical features of acne
A
- seborrhoea - excessive oiliness of the skin
- non inflammatory lesions - open and closed comedones
- inflammatory lesions including papules and pustules
- scarring
12
Q
Define the following:
- open comedone
- closed comedone
- Papule
- Pustule
- Nodule
- Cyst
A
- enlarged hair follicle opening filled with melanin. Blackhead
- small raised non-inflamed spot. Whitehead
- superficial inflamed spit without pus
- raised red lesions filled with pus (neutrophils)
- solid lesion that arises deep within the dermis/hypodermis. Frequently tender and painful. Not always visible
- A papule or nodule that is fluid filled
13
Q
- What is Atopic Eczema?
- What is the genetic component of eczema
- Where are scaly patches common in
a) infants
b) children and adults
A
- chronic inflammatory itchy skin condition developing in childhood
- FLG
3a) face and extensor aspects
3b) flexor aspects
14
Q
- What is a vesicle?
2. What is a bulla?
A
- small, fluid filled blister
2. large, fluid filled blister
15
Q
- What is psoriasis?
- What is Köebner phenomenon?
- What is a plaque?
- Name three common sites involved in psoriasis
- Name a life threatening complication of psoriasis
A
- chronic inflammatory skin disease due to hyperproliferation of keratinocytes and inflammatory cell infiltration
- linear eruption at the site of trauma
- palpable raised lesion, usually greater than 1cm
- extensors; behind eats; around nail bed
- erythoderma - inflammatory dermatosis affecting >90% of body surface
