Lecture 2 Flashcards
What does hair consist of?
Hair shaft
hair follicle
arrector pili muscle
sebaceous gland
What is the arrector pili muscle?
The muscle fibre component of tissue that causes hair to stand up and increases the insulation effect.
What is the Sebaceous gland?
Produces sebum which is a natural moisturiser and water repellent.
What causes Acne?
A blockage of hair follicles, infection and increased sebum.
Role of sweat glands?
- Eccrine (everywhere) Thermoregulation - Apocrine (Specialised) Situated deeper in skin secretes oily substances(eg pheromones) into base of hair follicles.
Types of receptors?
Tactile
Lamellar
Bulbous
Role of Nails?
Protect fingertips
Enhance sensation
Where is melanin produced?
Melanocytes (cells)
How to melanocytes transfer malenin to epidermal cells?
Melanosomes (vesicles containing melanin)
What causes a mole?
Clusters of melanocytes can be caused by sun exposure - overproliferation.
What causes a freckle?
Melanocytes overproducing melanosomes, triggered by sun exposure.
Where are Melanocytes located?
Deep within the skin, on stratum basale at the bottom of the basement membrane. Although the skin in this layer doesn’t shed, melanocytes do.
Where are malenosomes located?
Throughout the epidermis, they shed with keratinocytes.
Why is VItamin D important?
Essential for normal calcium metabolism and strong bones. UV exposure is required for Vitamin D syn thesis.
What are the two types of skin cancer?
Basal Cell Carcinoma - Stratum Basale (common but benign).
Malignant Melanoma - melanocytes (more dangerous).
