The Integumentary System Flashcards
What is the epidermis?
Outermost layer, protective layer, prevents water loss, melanocytes produce melanin which protects against UV damage.
Melanocytes are specialized cells that produce the pigment melanin, which absorbs UV radiation.
What characterizes the stratum corneum?
Top layer, dead flattened keratinized cells, contains lipid-rich cells that form a barrier to water evaporation preventing dehydration.
This layer is crucial in preventing transepidermal water loss.
Where is the stratum lucidum found?
Only in thick skin - thin transparent layer of dead cells found on palms and soles.
The stratum lucidum provides an additional barrier in areas of high friction.
What occurs in the stratum granulosum?
Cells begin to flatten and accumulate keratin.
Keratin is a key protein that helps in the waterproofing of the skin.
What is the function of the stratum spinosum?
Contains spiny cells that provide strength and flexibility.
This layer is vital for maintaining the structural integrity of the skin.
What happens in the stratum basale?
Deepest layer, where new cells are generated; contains melanocytes.
This layer is also known as the stratum germinativum.
What is the role of the dermis?
Middle Layer - composed of dense connective tissue, provides skin elasticity and strength from collagen, nerve endings detect stimuli, supplies nutrients to the epidermis, regulates body temperature by adjusting blood flow, sweat glands, oil secretion.
The dermis is essential for the overall function and health of the skin.
What are the components of the papillary layer?
Thin, upper layer containing loose connective tissue, capillaries, and sensory neurons.
The papillae form the ridges of fingerprints, enhancing grip.
What characterizes the reticular layer?
Deeper, thicker layer made of dense connective tissue that contains larger blood vessels, sweat and sebaceous (oil) glands, hair follicles, and deep pressure receptors.
This layer is crucial for housing the skin’s appendages.
What is the hypodermis?
Deepest Layer, mostly adipose tissue (fat) and loose connective tissue, helps conserve body heat, provides cushioning from mechanical trauma, acts as energy reserve, connects skin to underlying muscles and bones, allowing skin mobility.
The hypodermis plays a significant role in thermoregulation.
What is the hair shaft?
Visible above skin surface.
The hair shaft is the part of the hair that is not embedded in the follicle.
Where is the hair root located?
Embedded within dermis.
The root is the part of the hair that is still growing.
What is the hair follicle?
Tube-like depression where hair cells divide and grow.
The follicle is essential for hair growth and regeneration.
What is the bulb in relation to hair?
Base of the follicle where hair cells divide and grow.
The bulb contains the actively dividing cells that produce hair.
What does the arrector pili muscle do?
Attached to hair follicle, causes goosebumps by contracting in response to cold and fear.
This muscle helps in thermoregulation and can make hair stand up.
