Lab 2.1 Flashcards
Epidermis
Structure?
Function?
The outer, thinner layer conprised of a stratified squamous epithelium
-Prevents water loss and entry of chemicals and microorganisms, protects against ultraviolet light, produces vit D
Dermis
Structure?
Function?
Inner, thicker connective tissue layer - 2 layers
Responsible for structural strength and flexibility of the skin. Epidermis Exchanges gases, nutrients and waste products with the blood in the dermis
What are the accessory structures of the integumentary system?
Sweat glands
Hair
nails
sebaceous glands
What are the 5 layers of the epidermis?
Stratum basale - bottom later
Stratum spinosum
Stratum granulosum
Stratum lucidum - not present in thin skin
Stratum corneum - top layer
Name the layer
Which layer in epidermis?
of layers / cell type
Structure?
Function?
Stratum Basale
- Deepest portion of epidermis
- Single layer of cubodial or columnar cells
- Epidermis is anchored to basement membrane with hemidesmosomes
- Melanocytes produce and contribute melanin, which protects against ultra violet light
Name the layer
Which layer in epidermis?
of layers / cell type
Structure?
Function?
Stratum spinosum
- on top of stratum basale (2nd layer up)
- Composed of 8-10 layers of many sided cells, as they push to the surface they flatten - desmosomes break apart and reform
- Keratin fibers and lamellar bodies form inside the cells
Name the layer
Which layer in epidermis?
of layers / cell type
Structure?
Function?
Stratum granulosum
3rd layer up
- 2-5 layers of flat diamond shaped cells
- produces keratohyalin granules, lamellar bodies release lipids from cells, cells die
Subcutaneous tisse
Structure?
Function?
Not part of the skin, loose connective tissue with abundant deposits of adipose tissue
Attaches dermis to underlying structures, provides energy, insulation and padding
Name the layer
Which layer in epidermis?
of layers / cell type
Structure?
Function?
Stratum lucidum
4th layer from bottom
3-5 layers of dead cells, present in thick skin only
-Disperses keratohyalin around keratin fibers
Name the layer
Which layer in epidermis?
of layers / cell type
Structure?
Function?
Stratum corneum
top layer / superficial part of skin
25 or more layers of dead squamous cells
Name the structure
- fingerlike projections arranged into double rows
- increasing the surface area between the epidermis and dermis
- strengthening the juncture with the epidermis and increasing the amount exchange of oxygen, nutrients, and waste.
Name the gland
Apocrine sweat gland
continuously secrete a concentrated fatty sweat into the gland tube
Simple cuboidal,. large lumen
Name the gland
Eccrine/Merocrine sweat gland
Stratified cuboidal - Small lumen
Eccrine glands occur over most of your body and open directly onto the surface of your skin.
Name the gland
Sebaceous glands
a small gland in the skin which secretes a lubricating oily matter (sebum) into the hair follicles to lubricate the skin and hair.
Name the structure
Lamellated corpuscle
are one of the four major types of mechanoreceptor. They are nerve endings in the skin responsible for sensitivity to vibration and pressure.
Name the structure
Tactile (Meissners) corpuscle
Tactile is flat and lamellated has a shape.
tactile provides fine touch, to judge texture including the lips, palms and nipples
Name the structure
Medulla
Name the structure
Cortex
Provides strength, structure, color and texture
Name the structure
Cuticle
Protects the cortex
Name the structure
Internal epithelial root sheath
surrounds and protects the growing hair
Name the structure
External epithelial root sheath
Name the structure
Hair bulb
forms the base of the hair follicle. In the hair bulb, living cells divide and grow to build the hair shaft.
Name the structure
Hair papilla
The dermal papilla consists of mesenchymal cells in the hair follicle, which plays the main role in the regulation of hair growth.
Name the structure
Arrector pili muscle
Attached hair follicle at one end and to dermal tissue on the other end.
In order to generate heat when the body is cold, the arrector pili muscles contract all at once, causing the hair to “stand up straight” on the skin.
Identify the structures
1-6
- Arrector pili muscle
- Sebaceous gland
- External root sheath
- Dermal papillae
- Hair bulb
- Hair follicle