Unit 9: Integumentary System Flashcards
What are the layers of the epidermis of thick skin? (deep to superficial)
Stratum Basale
Stratum Spinosum
Stratum Granulosum
Stratum Lucidum
Stratum Corneum
What layer is thin skin missing that thick skin has?
The Lucidum layer
What are the 2 main layers of skin?
Epidermis (superficial)
Dermis (deep)
What type of epithelium makes up the epidermis? Is it vascular?
The epidermis has a stratified squamous epithelium. It is avascular
What is the stratum basale and what are the 2 cell types?
A single row of cells made up of keratinocytes (90%) and melanocytes (10%)
Keratinocytes make up the majority of the basale layer. They actively undergo mitosis, make keratin (tough protein), and get pushed towards the surface as new cells get produced. What are melanocytes?
Melanocytes produce a pigment (melanin) for UV light protection. It also affects the colour of skin we have, depending on the shade/amount of melanin produced
At what layer of the epidermis does mitosis stop?
Stratum granulosum
What does the stratum granulosum contribute to the epidermis?
It contains granules that help produce keratin (strength) and start to produce waterproofing glycolipids (prevents water loss). It is the last layer of living cells
What is the stratum corneum?
20-30 layers of flat, dead cells filled with keratin and surrounded by waterproofing glycolipid
The dermis contains blood vessels, nerves, glands, hair follicles, and arrector pili muscles. What are the 2 layers of the dermis?
The papillary layer, which is areolar CT that is connected to the epidermis.
The reticular layer, which forms most of the dermis, is made of dense irregular CT, and sits between the papillary layer and hypodermis
What are dermal papillae?
Projections into the epidermis by the papillary layer. In thick skin these form epidermal ridges
What are the different types of epidermal derivatives?
Hair, nails, skin exocrine glands
What are the 3 parts that make up a hair follicle?
The epithelial root sheath
The bulb
The matrix
What things are associated with each hair follicle?
Outer CT sheath, hair papilla, root hair plexus, sebaceous (oil) gland, arrector pili muscle (smooth muscle)
What are human nails?
Very heavily keratinized epidermal cells consisting of the nail root, body, and free edge
What are the 4 skin exocrine glands?
Sebaceous glands
Sudoriferous glands
Ceruminous glands
Mammary glands
This gland is mainly connected to hair follicles and secretes sebum (oily) to soften and lubricate hair and skin
Sebaceous glands
This gland is the primary sweat gland with secretory portions in the dermis of both thick and thin skin
Sudoriferous glands
This modified sweat gland is in the ear canal and produces ear wax
Ceruminous glands
What are the 4 major types of cutaneous sense receptors?
Touch receptors
Pressure receptors
Thermoreceptors
Nociceptors
What are the 3 types of touch receptors?
Free nerve endings (in epidermis)
Root hair plexuses
Tactile (Meissner’s) corpuscles (in dermal papillae)
What are the 2 types of pressure receptors?
Free nerve endings (in dermis)
Lamellar (Pancinian) corpuscles (deep in dermis or hypodermis)
What type of cutaneous sense receptors are free nerve endings for pain?
Nociceptors
What causes albinism?
A lack of melanin production by melanocytes
What is psoriasis?
An autoimmune disorder that causes accelerated mitosis of keratinocytes in the stratum basale, which results in the growth of a thick, scaly area on the surface of the skin
True or false: the deepest part of the skin is the hypodermis
False. The hypodermis is not considered part of the skin
Which layer of skin is responsible for fingerprints?
Papillary dermis
