Glands And Skin Flashcards
What is the dermis made up of?
Blood vessels and excretory glands (sebaceous and sweat glands)
What is the hypodermis made of?
Adipose cells and macrophage
What are the functions of skin? (7)
- Protection
- Sensation
- Insulation and thermoregulation
- Excretion and secretion
- Immunity
- Endocrine
- Growth
What does the skin protect against? (4)
- Excessive UV radiation
- Bacterial and viral microorganisms
- Dehydration
- Dangerous chemicals
Which type of cell does the epidermis contain?
Merkel cells
What is transepidermal water loss?
Excreting water to the skin’s surface via diffusion
Complete the sentences:
Cells in the epidermis can produce vitamin __ (cholecalciferol) by using energy in __ radiation. In the liver, it is converted into _________. In the kidneys, it is then converted to __________ (the active version of vitamin D).
D3
UV
Calcidiol
Calcitriol
What does calcitriol regulate?
The amount of calcium and phosphate ions in the skin
What do melanocytes produce?
Melanin
Where are melanocytes found?
At the epidermal/dermal junction
Complete the sentence:
The formation of melanin occurs in an intracytoplasmic membrane-bound organelle called a __________.
Melanosome
Complete the sentence:
The melanosome is transported by ____________ towards the surface of monocyte to neighbouring ____________.
Microtubules
Keratinocyte
True or false: in the keratinocyte, the melanosome accumulates in the super nuclear region of the cytoplasm and this protects the nuclei of dividing cells from the damaging effect of the sun (UV)
TRUE
Why is early detection of melanoma critical?
Because there is no cure for late stage melanoma
How does UV radiation affect DNA bases?
When UV radiation is absorbed by the double bond in thymine, the double bond opens and the base reacts with the nearby molecule. If the UV modified thymine is adjacent to another thymine on the same DNA strand, the two molecules form a thymine dimer and this results in a four-membered ring
