How many layers or strata are there to the epidermis?
Five
What are the layers of the epidermis?
Stratum corneum
Stratum Lucidum
Stratum granulosum
Stratum spinosum
Stratum basale
What is another term for the stratum granulosum layer
Granular cell layer
What is another term for the stratum spinosum?
Prickle cell layer
What is another term for the basale layer
Germinative layer
What is the purpose of keratin?
A waterproof protein that gives the skin mechanical strength and flexibility
What happens at the stratum lucidum layer?
Here cells die and lose their neclei and organelles when they become full of keratin
What happens at the stratum granulosum layer?
Cells in this layer become fillsed with granules and secrete a waterproof liquid
Describe the stratum spinosum layer?
Cells are tightly joined by spinelike projections which give them a prickly appearance
Describe the stratum basale layer
Contains stem cells that divide and providecontinual renewal of cells
Most of the cells that make up the epidermis are called
keratinocytes
What cell layer are melanocytes found
Stratum basale
Describe the purpose of the dermal papillae
Extensive networks of capillaries in the papillae deliver oxygen and nutrients to the cells of the epidermis and also functions in temperature regulation
What muscles are associated with hair follicles?
Arrector pili muscles
What substance does the sebaceous glands produce?
Oily material known as sebum
Sebaceous glands are attached to what?
Hair follicles
Sebaceous glands are most numerous on
The face and scalp
Which layer of the skin contains the glands
Dermis
What structures make up the integumentary system
Skin
Hair
Nails
Glands
What is the epidermis
Outermost keratinized stratifies squamous epithelium covering the surface of the skin
What is a stratum
a single layer of epithelial cells
What is melanin
Brownish-black pigment substance produced by melanocytes
What is the chief function of melanin
absorption of UV rays
What two substances is the epidermis rich in
Keratin and melanin
Describe the dermis
The main dense fibrous connective tissue portion Contains collagen fibers
Describe the subdermis
Subcutaneous connective tissue layer
Mainly consist of adipocytes
Sudoriferous glands secrete
sweat
Describe what the endocrine glands do
They release their product or hormones into the surrounding tissue fluid