Lecture Midterm 2 Flashcards
Function of stratum corneum
Creating a strong water, resistant barrier of dead, keratinocytes and lipids
Function of integumentary system
Protective covering, sensory input, temperature regulation, vitamin D synthesis, excreting, small amounts of waste, metabolizes some chemicals
What is stratum lucidum and where do you find it?
In histology, it appears to be a thin, clear, layer. you can find the stratum lucidum on the soles and palms
What is stratum granulosum?
A layer of keratinocytes that are beginning to die, shedding their organelles that appear granulated due to the lipid and keratin granules present.
What is stratum spinosum?
There are keratinocytes that are more round in shape, because they are new, they are becoming more differentiated. Neuron endings are found here as well as immune cells.
What types of cells are found in Stratum basale?
Epidermal, stem cells, melanocytes, some sensory cells
What are the typical cytoskeletal proteins found in epithelial cells?
Keratin
How many layers is the stratum basale?
One
How does the integumentary system act as a protective barrier?
Prevent infection, prevent water loss and ion loss
What are the three layers of the integumentary system?
Number one: Epidermis
Number two: dermis
Number three: hypodermis
What are the five layers of the epidermidis from superficial to deep?
- Stratum corneum
- Stratum lucidum
- Stratum granulosum
- Stratum spinosum
- Stratum. Basale
What are the two layers of the dermis from superficial to deep?
- Papillary layer of the dermis
- Reticular layer of the dermis
What type of connective tissue is mostly found in the papillary layer of the dermis?
Loose areolar connective tissue
What are the bumps at the top of the dermis called
Dermal papillae
What is the function of blood vessels in the dermis?
To bring nutrients, oxygen, assist in temperature regulation
What are the sensory endings at the top of the dermal layer known as?
Meissner’s corpuscles
What is the main type of cell present in the dermal layer?
Fibroblasts
What type of fibers is the dermal layer comprised of?
Collagen (type one and type three), elastic
What is the thickest layer of the skin?
The reticular layer of the dermis
What can be found in the reticular layer of the dermis?
Collagen, fibers, elastic fibers, fibroblasts, blood vessels, hair follicles, eccrine sweat glands, pacinian corpuscles,
What is the type of tissue that comprises the reticular layer of the dermis?
Dense irregular connective tissue
Which layer provides the most structure and support to the skin?
The reticular layer of the dermis
COL1A1 gene is responsible for what?
Synthesis of collagen fibers in connective tissue for dermis, bones, and tendons
What is osteogenesis imperfecta?
A mutation in the collagen one alpha one gene on the 17th chromosome.
What is Ehlers-Danlos syndrome?
A mutation of the collagen one alpha one gene located on chromosome 17
What is Epidermolysis bullosa?
A mutation of the collagen, seven alpha one gene which disrupts the basement layer, and makes skin detach from every day activities, such as brushing, teeth or flossing patients lose their epidermidis at an abnormal rate, are susceptible to bleeding and higher incidence of infection
What is the function of the hypodermis?
Energy storage, insulation, cushion, defense
What is the function of melanocytes?
Produce melanin to be carried by keratinocytes
What is the function of melanin?
It is held in keratinocytes to shield the nucleus from further radiation exposure from UV rays, this is to reduce the risk of DNA mutation
What is RSH Melanocortin?
A ligand that stimulates melanin production within melanocytes
What are the package to particles of melanin referred to as?
Melanosomes
What is the result of TYR, TYRP1, OCA2 gene mutations?
Albinism, which affects hair, eyecolor, and skin color. It is an autosomal recessive gene mutation.
Glands and hair follicles are derived from what type of tissue and cells?
Epithelial tissue
What is the role and function of sebaceous glands?
Producing and excreting, a substance called sebum, which is utilized to moisturize the epidermidis layer and hair. It is an oily substance.
What is the function of eccrine sweat glands?
De secrete sweat to the surface of the skin and are utilized in temperature regulation.
What is sebum from a chemical perspective?
squalene, esters of glycerol, wax and cholesterol, as
well as free cholesterol and fatty acids
Where are multipotent stem cells found?
hair bulge, hair bulb, dermal papilla
