5.1 Structure of the Skin Flashcards
Names for skin
Cutaneous membrane or integument
Skin properties
Covers surface of body
largest organ
1.8m ^2
Contains all 4 types of tissues (what makes it an organ)
Integumentary system
Made of skin and accessory organs
Regions of the skin
Epidermis and dermis
Hypodermis
Subcutaneous tissue - attaches skin to underlying tissue
Epidermis location
Outer, thinner region of skin
Epidermis cells
Squamous epithelium
Layers of epidermis
Layers- strata
Deep to Superficial
Stratum basale
stratum spinosum
stratum granulosum
stratum lucidum
stratum corneum
Stratum basale location
Superficial to the dermis
Bottom layer of epidermis
Stratum basale cell division
Cells constantly divide and new cells are pushed up
they die and slough off
Stratum basale cells
Keratinocytes
Langerhans cells
Melanocytes
Kerattinocytes
found in stratum basale
most numerous
produce keratin
Keratin
A water proofing protein
Langerhans cells
Found in stratum basale
macrophages - a type of white blood cell
works to fight infection
Melanocytes
Found in stratum basale
produce melanin
give us our skin color and protection from UV radiation
Albanisms
defective melanin
Sensory nerves in stratum basale
Free nerve endings
Tactile (merkel) cells
Free nerve endings
give us pain and temperature sensations
found in stratum basale
Tactile cells
Merkel cells
found in stratum basale
give us touch sensations
Stratum Spinosum
Cells divide like stratum basale
Spiny appearance due to keratin fibers
Stratum granulosum
Flattened cells
lots of keratin and dark-staining pigment granules
Stratum lucidum
found in thick skin
deep to stratum corneum
provides protection from friction
Stratum corneum location
tough, uppermost layer of epidermis
Stratum corneum cells and function
Cells are keratinized (hardened) and dead - prevents water loss/gain
Serves as a mechanical barrier against microbes
Dermic properties
Thicker than epidermis
dense irregular connective tissue
Dermis anchoring
Dermal papillae in most superficial layer - anchor to epidermis, uneven areas create fingerprints
Fibers of dermis
Collagenous
Elastic
sensory nerve fibers
Collagenous fibers in dermis
Prevent skin from being torn
Elastic fibers in dermis
Stretch to allow movement of muscles and joints
Dermis - vascular
Vascularization supplies oxygen and nutrients to cells of the dermis and epidermis and causes temporary skin color change (flushing of skin)
-dermis contains blood vessels that transport oxygen
Hypodermis location
Subcutaneous layer - below dermis
Hypodermis tissues
Adipose tissue provides energy storage, insulation, and protective padding
loose connective tissue
Hypodermis injections
Subcutaneous injections are given with a hypodermic needle
