Integumentary System Flashcards
How many of the 4 tissue types does the integumentary system have?
All 4: epithelial, connective, muscular, and nervous
What functions does the integumentary system have?
Temp regulation Synthesis of vitamins Appearance Protection Water conservation Sensory receptors
What kind of tissue I the epidermis composed of?
Epithelial tissue
What are the tissues the dermis is composed of?
Connective, muscle, nerve
What are the most abundant cells in the integumentary system?
Keratinocytes
What are the 4 main cells in the skin?
Keratinocytes, melanocytes, langerhans cells, and merkel cells
What is the function of keratinocytes?
Water proofing
What do melanocytes do?
Produce melanin to protect from sun exposure
Langerhans cells work by…
Fighting off infection
Merkel cells are…
Sensory cells; Found in deep layers of the dermis
Name the 5 layers of epidermal cells
Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale
Stratum basale (germinativum)
The growing layer of the epidermis; has merkel cells, melanocytes, keratinocytes, and stem cells that divide rapidly.
Stratum spinosum
Has spiny projections that bind cells; 8 to 10 cells thick; strong and flexible; take I melanin from near by melanocytes by phagocytosis
Stratum granulosum
3-5 layers of flattened keratinocytes undergoing apoptosis (degeneration);
Contain dark staining keratohyalin granules and lamellar granules (waterproofing)
Keratinhyalin are found where
Found in keratinocytes of the stratum granulosum layer
Stratum lucidum
Thick skin found on the palms and the bottoms of the feet
Stratum corneum (horny layer)
25 to thirty layers of flat dead cells filled with keratin and surrounded by lipids; protect from light, water, chemicals, heat, &bacteria
What accelerates or regulates the growth of the skin
Epidermal growth factor (EGF); a hormone like protein
Melanocytes
Produce the protein melanin when stimulated by UV or MSH (melanin stimulating hormone) which is made during the process of making ACTH
-keratinocytes takin in melanin through phagocytosis
When bilirubin builds up in the skin what does this cause and what is it a sign of?
Causes jaundice which is an indicator of liver problems
What is the dermis composed of?
- collagen, elastic fibers, fibroblasts, macrophages, and far cells
- contains hair follicle, glands, nerves, blood vessels
- mainly connective tissue
What are the two main regions of the dermis
Papillary
Reticular
Papillary region
Top portion of the dermis composed of loose connective tissue and elastic fibres
Anchors epidermis to dermis
Contains Meissner’s corpuscles (touch)and free beer endings ( pain and temp)
Reticular region
Bottom half I the dermis
- dense irregular connective tissue
- interlacing collagen and elastin
- has sweat gland ducts, sebaceous glands, and hair follicle
- provides strength extensibility and elasticity
