integumentary slide 1-19-mace-exam 1 Flashcards
Integument system is composed of 2 things:
- skin
2. The derivatives of skin
Skin– also known as ____ _____
cutaneous membrane, or integument
Skin is composed of: (2 things)
- epidermis (epithelium
- Dermis (CT)
Derivatives of skin=
hairs, sweat glands, sebaceous glands, ceruminous glands, nails
Hypodermis is composed of which 2 types of CT?
- adipose
- areolar
T/F: hypodermis is a part of the skin
FALSE! it’s not a part of the skin, but is studied together with the skin because their close relation
The dermis is made up of which 2 layers:
- papillary layer (more superficial) –> contains Epidermal ridge and Dermal papilla
- Reticular layer (deeper)–> contains hair follicles, arrector pilli muscle, sebaceous glands, sweat gland ducts, merocrine glands
Skin is considered the largest organ in human body, making up ____ % of the body weight
7-8%
Epidermis is composed of which type of epithelium?
keratinized stratified squamous epithelium
Which cell type primarily makes up the epidermis
primarily keratinocytes
The epidermis, contains 4-5 layers depending on the location, name them from deepest to most superficial
stratum basale stratum spinosum stratum granulosum stratum lucidum stratum corneum (Britney spears gets long )
Which layers of the epidermis contain living keratinocytes?
first three layers (deepest layers)
-stratum basale
stratum spinosum
stratum granulosum
Which layers of the epidermis contain dead keratinocytes?
most superficial 2 layers:
- stratum lucidum (only in thick skin– deep to the stratum corneum)
- stratum corneum
Stratum Basale aka
stratum germinativum or basal layer
Describe the stratum basale
- Deepest epidermal layer
- Single layer of cuboidal to low columnar cells
- Attached to underlying basement membrane which separates the epidermis from the dermis
- Contains sensory nerve endings for sensing pain and temperature
- **contains 3 cell types
List the 3 cell types of the stratum basale
- keratinocytes
- Melanocytes
- Tactile Cells (merkel cells)
Describe keratinocytes in the stratum basale
many keratinocytes stem cells present in this layer, that divide to regenerate new cells–> replace old cells shed at the surface
Describe the function of Melanocytes in the stratum basale
Melanocytes–>produce & store melanin in response to UV light, transfer pigment granules into keratinocytes, accumulate around nucleus of keratinocytes, shield nuclear DNA from UV radiation, **responsible for the darker tones of skin
Describe the function of tactile cells in the stratum basale
aka (Merkel cells) are sensitive to touch, when compressed, release chemicals to stimulate sensory nerve endings
Stratum spinosum aka ______
spiny layer
Describe the stratum spinosum:
- cell type?
- contains?
=Several layers of polygonal keratinocytes
- Daughter cells from stratum basale are pushed into this layer to become specialized, non-dividing keratinocytes, some in deepest level still dividing cells
- **Contains sensory nerve endings for sensing pain and temperature
- also contain epidermal dendritic cells (Langerhans cells)
Fx of Dendritic cells
aka Langerhans cells (in the stratum spinosum)
Fx: -immune cells that help initiate immune response
-responsive to pathogens and epidermal cancer cells
Stratum Granulosum aka
granular layer
Describe the cell type contained in the stratum granulosum and what occurs in this layer
- contains 3-5 layers of keratinocytes
- located Superficial to the stratum spinosum
- **First layer of keratinization