Skin Flashcards
Is skin an organ?
Yes, largest in the body
What are the epidermal cells in skin classed as?
Keratinocytes
What is the function of the epidermis?
Prevents water loss by evaporation
What is the function of the dermis?
Reduces risk of external injury Maintains the epidermis through its blood flow Permits body cooling Involved in immune surveillance Gives UV protection Stores energy Provides sensory information.
What is the epidermis made of and what does it separate?
Epithelial tissue
Forms a boundary between internal and external compartments
What is the dermis made of?
Connective tissue
What is the layer below the dermis called and is it classed as skin?
Hypodermis
It is adipose connective tissue, which anchors skin to underlying structures. It is NOT part of skin
What are the 4 cell types the epidermis is made from?
Keratinocytes
Melanocytes - pigmant formation
Langergans cells - Immune surveillance
Merkel Cells - touch receptors
From bottom to top, what are the 5 layers of the epidermis?
Stratum Basale
Stratum Spinosium
Stratum Granulosum
Stratum Lucodum/Corneum (difficult to distiguish from each other)
What are the 2 layers of the dermis?
Papillary layer
Reticular layer
Describe the papillary layer.
Is made of loose CT and is cellular as its made up of macrophages.
Has an irregular interface with the epidermis and is protective against pathogens.
In blood vessels -thermoregulation and nutrition
Is also in nerve endings
Describe the reticular layer.
Dense irregular CT
Collagen bundles in 3 planes
Made up of elastic fibers, elasticity is lost with age.
What makes skin waterproof?
Keratin in epidermis
Intercellular spaces have lipid “cement”
What is skin colour affected by?
Blood
Carotene
Melanin
What type of glands are the sweat glands, what is its name and where is it found?
Simple tubular
Eccrine sweat gland
Dermis