Module 8 Flashcards
The skin is also called the _____ system or ________.
integumentary or cutaneous membrane
_______ hold cells together.
Desmosomes
______ hold the epithelium to the basement membrane.
hemidesmosomes
From the outside, in, the layers of the skin include the ______, ______, and _______.
epidermis,
dermis,
subcutaneous (hypodermis)
The epidermis is mostly comprised of dead cells, which have expelled their nucleus and all organelles and become simply bags of proteins called ______.
keratin
Hair roots are found in the dermis, and there is a small bit of muscle (the ________) which controls the angle of each hair.
arrector pili
Beneath the dermis is the _______. This is not technically part of the skin but is a layer of areolar and/or adipose connective tissues
subcutaneous layer
One dermatological disease that is very troubling is _______. This disease involves an autoimmune attack against the desmosomes.
pemphigus
The skin is a keratinized stratified squamous epithelium. From the deepest to the most superficial, the layers are: \_\_\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_\_\_\_ (only in thick skin) \_\_\_\_\_\_\_\_\_\_\_. A pneumonic for these layers from deep to superficial is: Before Signing, Get Legal Counsel or for superficial to deep is: Cher Likes Getting Skin Botoxed
stratum basale; stratum spinosum; stratum granulosum; stratum lucidum (thick skin) stratum corneum
Keratinocytes are constantly made in the stratum basale. As cells are pushed superficially, they lose their nucleus and organelles and become dead bags of keratin. These cells are also called _______.
corneocytes
Corneocytes are constantly shed from the surface of the stratum corneum. The shed flakes are called _____.
squames
_____, which covers everything except the palms, fingertips, and soles of the feet, is about 0.1mm thick.
Thin skin
______, also called glabrous skin, is found on the ventral (palmar) surface of the hands (palms and fingertips) and on the soles (plantar surface) or the feet.
Thick skin
What are the 4 cell types of the epidermis?
Keratinocyte;
Melanocyte;
Intradermal macrophage (Langerhans) cell;
Tactile epithelial (Merkel) cell
______ (a cell membrane surrounding the protein keratin) make up about 90% of the cells of the epidermis.
Dead keratinocytes
About 8% of the cells are ______, cells which produce and carry pigment granules that give the skin it’s color.
melanocytes
More rarely, we find ______, which is the skin’s version of a type of immune cell called a dendritic cell.
Langerhans cells
The rarest epidermal cell is the ______, a type of nervous system cell that detects light touch.
Merkel disc
The color of the skin comes from 3 classes of pigment: ______, _______, and ______.
melanin,
hemoglobin,
carotene
What are the 2 kinds of melanin?
pheomelanin,
eumelanin
This kind of melanin is yellow to red.
Pheomelanin
This kind of melanin is brown to black.
eumelanin
In hair, pheomelanin and eumelanin granules are scattered among the keratin fibers. In skin, these pigments are produced in cells called ______.
melanocytes
Melanin is made from the amino acid tyrosine in an organelle called the _______.
melanosome
The _______ is the connective tissue layer beneath the epidermis.
dermis
What are the 2 regions of the dermis?
papillary region and reticular region
The ______ is about a fifth of the thickness of the dermis.It is thrown up into the ridges that penetrate up into the epidermis and each of theses tends to contain blood vessels and the sensory structures known as Meissner corpuscles and free nerve endings.
papillary region
The _____ is where the nerve and blood vessels run through the dermis. Also, hair roots (if present) and glands are found here as well.
reticular region
Stretching, such as from obesity or pregnancy, can cause tears in the dermis. These are seen on the skin surface as _____ (or, more commonly, “stretch marks”).
striae
______ is the superficial portion of the dermis(about 1/5); consists of areolar connective tissue with thin collagen and fine elastic fibers; contains dermal ridges that house blood capillaries, corpuscles of touch, and free nerve endings.
Papillary
______ is the deeper portion of the dermis (about 4/5); consists of dense irregular connective tissue with bundles of thick collagen and some coarse elastic fibers. Spaced between fibers contain some adipose cells, hair follicles, nerves, sebaceous glands, and sudoriferous glands.
Retilcular
The subcutaneous layer of the skin is a typical example of an ______, which is a loose connective tissue made up of collagen, reticular and elastic fibers with adipose (fat) cells suspended in the fiber matrix.
areolar connective tissue
What are the 2 types of sweat glands?
eccrine and apocrine
_____ sweat glands are used to cool the skin and restore homeostasis.
Eccrine
_____ sweat glands produce a more viscous secretion that eccrine sweat glands. These secretions contain pheromones.
Apocrine
______ glands are most often found opening onto the neck of the hair follicle.
Sebaceous
Sebaceous glands produce an oily secretion, called ______.
sebum
_____ is the portion of the nail that is not visible.
nail root
_____ (cuticle) is the stratum corneum of the epidermis.
Eponychium
______ is the thick, white part of the nail.
Lunula