Chapter 5 Test Review Flashcards
Components of integumentary system
Skin
Accessory structures
Functions of skin
Covers and protects the body and deeper tissues from injury, dehydration, invasion of pathogens and UV radiation
Regulates body temp
Produces keratin and melanin
Collects sensory info
Excretes small amounts of waste products
Components of skin
Outer epidermis
Inner dermis
Epidermis
Keratinized squamous epithelium
Cells: keratinocytes, melanocytes, merkel cells, langerhans cells
Dermis
Loose/areolar tissue in the papillary layer
Dense irregular tissue in the reticular layer
Dermal papillae
Interlocking mechanism between dermis and epidermis
Stratum basalt form epidermal ridges that extends between adjacent dermal papillae in the dermis
Structures responsible for fingerprints
Epidermal ridges
Keratinocytes
Most numerous- 90% of all skin cells
Soft on skin, hard on hair/nails
Melanocytes
8% of skin cells
Located mostly in the stratum basale. Produce melanin
Protects dermis from UV radiation
Determines skin color
Merkel cells
Located mostly in the stratum basale
Part of sensory receptors
Langerhans cells
Located mostly in the stratum spinosum
Dendritic cells belonging to the immune system
Protect the skin and deeper tissues from pathogens
Layers of the epidermis
Stratum corneum
Stratum granulosum
Stratum spinosum
Stratum basale
Life cycle of a keratinocyte
Mitosis occurs in the stratum basale andstratum spinosum
As new cells are generated they push older ones toward the surface where they die and are sloughed away
Difference between thick and thin skin
Thick skin has an additional layer, the stratum lucidum
Thin skin is found everywhere on the body, thick skin is only on the palms and soles of feet
Structures found in the dermis
Sweat glands
Sebaceous glands
Hair follicles
Hair/nails
