Part 4: Integumentary system Flashcards
Membranes Composed of
epithelium (epidermis) & connective tissue (dermis)
type of membrane skin
cutaneous membrane(epidermis +dermis)
skin heals ___
easily
accessory structures of skin
Exocrine glands
Hair
Nails (variant of hair)
Major functions of skin
- a barrier
- Thermoregulation
- Sensation
- Metabolic functions (vitamin D, subcutaneous fat)
- Social functions (identity of social animals)
constriction- heat ____, dilation- heat ____
in
out
All 4 tissue types are represented in ____
skin
Skin structure
- Epithelium
- Connective tissue
- Muscle (smooth muscle)
- Nerve
nerve of skin does what?
-Controls the smooth muscle in CT
- Generates sensation (tactile,pressure, temperature, pain)
- Stimulates exocrine glands
Muscle of skin does what>
Controls the diameter of blood vessels /hair position
CT of skin does what?
-Supports epithelial tissue
-Provides strength & elasticity
-Important for thermoregulation
Structure of epidermis (5 layers) -superficial to deep (Come, Let’s Get Sun Burnt)
-Stratum corneum
-Stratum lucidum* (in non-hairy skin only)
-Stratum granulosum
-Stratum spinosum
-Stratum basale (germinativum)
_____cells producing keratin (tough protein that helps epidermis with its protective properties)
Keratonized stratified squamous epithelial
structure of dermis
-dermal papilla
dermis reticular layer (scaffolding)
Stratum germinativum (basal layer) is ____ composed of _____
the deepest layer composed of large cuboidal basal stem cells and 2 other types of cells (Merkel cells & melanocytes)
in stratum germinativum, stem cells constantly divide to give rise to ____
new keratinocytes (most abundant epithelial cells in epidermis)
Keratinocytes synthesize _____ which is a _____
keratin
tough fibrous protein to replace the dead ones that flake off
Stratum germinativum forms ____. makes sure that _____
basal lamina; this makes sure that the epithelium is firmly attached to the basal membrane (with CT – dermis)
Merkel (tactile) cells is ____ cell type but abundant ______. It is important for ____ because it has _____ receptor. It interacts with _____ fibre collectively called ____
-least common
-where skin has no hair (fingertips, lips)
-touch sensation
-sensory touch receptor - tactile
- dermal nerve fibre
-Tactile (Merkel) disc
Melanocytes synthesizes _____ by transferring _____ to ______. They contain ______ between _____.
of melanocyte cells depend by region of the body (ex. palm of hand) but NOT by people
melanin pigment
melanin granules to keratinocytes
long and slender processes
keratinocytes
Melanin granules are _____by keratinocytes – form _____ to protect DNA from _____.
phagocytized
“umbrella” over nucleus
UV radiation
What determines skin tone?
Activity (granules produced) of melanocytes
Stratum spinosum (spiny layer) composed of _____
several layers (8-10) of living keratinocytes & Langerhans cells
Stratum spinosum (spiny layer) have ______ that attach ______ together, providing ______ (gives the _____ appearance of layer)
desmosomes
keratinocytes
strength
spiny