Skin

Question 0

What is a pilosebaceous unit?

Answer 0

Hair follicles and sweat glands

Question 1

What does the dermis contain?

Answer 1

Fibroblasts, blood vessels, lymphatic vessels, mast cells, nerves

Question 2

What is a langerhans cell?

Answer 2

Dendritic bone marrow origin, found in prickle cell layer. Present antigens to T cells, mediate immune response

Question 3

Describe melanocytes

Answer 3

Dendritic neural crest origin, found in intervals along the basal layer of epidermis. Produce melanin

Question 4

What are the functions of skin?

Answer 4

Barrier, sensation, thermoregulation, psychosexual communication

Question 5

What are the four layers of skin?

Answer 5

Stratum corneum (horny layer), stratum granulosum (granular layer), stratum spinosum (prickle cell layer) and stratum basale (basal layer)

Question 6

Describe vascular thermoregulation

Answer 6

Dilation of skin blood vessels, heat loss, pallor, constriction and heat conversion

Question 8

Describe thermoregulatory eccrine sweating

Answer 8

Evaporation of eccrine sweating causes cooling - important for regulating temperature

Question 9

What is vitiligo?

Answer 9

Depigmentation of skin. Immune system attacks melanocytes

Question 10

What is alopecia?

Answer 10

An autoimmune response leading to hair loss

Question 11

Which stain is best for the dermo-epidermal junction?

Answer 11

PAS

Question 12

Describe apocrine glands

Answer 12

Most abundant in axillae, genital and submammary areas. Produce odourless, protein-rich apocrine secretion

Question 13

Describe psoriasis

Answer 13

Disorder of epidermal growth and differentiation. Cause is unknown but it is influenced by genes. Extreme proliferation of basal layer - gross thickening of prickle cell layer and excessive stratum corneum. Excessive scaling

Question 14

Describe malignant melanoma

Answer 14

Malignant tumour of melanocytes. Above epidermal basement membrane = good prognosis