Integument system Flashcards
What is the largest organ in the body?
Integument system
the integument system ranges in thickness, what is the smallest? biggest?
eyelid (0.5mm) to palms/soles of feet (5mm)
is the dermis vascular? is the epidermis?
YES, NO.
in hypodermis, what is there alot of?
adipose tissue
Where is thick skin found? how many layers? are hair follicles or sebaceous glands present? thick or thin stratum corneam?
palms and soles, 5 layers, no. thick.
Thin skin located where? thin or thick stratum corneum? how many layers?
everywhere else. thin. 4.
What are the five layers of thick skin? how does this differ from thin skin?
- Stratum corneum (most apical)
- Stratum Lucidum
- Stratum granulosm
- stratum spinosum
- stratum basal (most basal)
Stratum lucium only present in thick skin. the most thick layer in thin skin= spinosum.
How many layers thick is the stratum basal in both thin and thick skin?
ONE
Which layer do the cells being growing? Where are they sloughed off? Are cells in the stratum basal layer nucleated? what protein is present?
Cells start growing in stratum basal, sloughed off at stratum corneum.
anucleated, dead cells.
Keratin is present.
Stratum granulosm normally how many layers thick? what are major characteristics for identification?
Three
nuclei and granules.
Stratum lucidum is a flat layer of what kind of cells? what protein is present? what is unique about this layer?
translucent.
Eliedin.
only present in thick skin!
Stratum granulosm how many cell layers thick? what is contained in their granules? which is the last maturation stage of? initiates process of?
2-4
keratohyaline, last maturation stage of keratin (initiates process of keratinization)
protrusions into the stratum spinosum are called?
papillae
What kind of cells are present in the stratum spinosum? What stage of keratin maturation is here? what are the cells linked by in this layer?
polyhedral cells with spines. “prickle cells”
Cytokeratin forms “tonofibrils”->(keratin containing intermediate filaments)
Desmosomes
What kind of cells are present in the stratum basale? what connects cells to the BM? what connects them to each other?
cuboid or columnar keratinocytes
hemidesmosomes connects them to BM
desmosomes connects them to each other
Keratin matures in which layer? What is the process of maturation involving the stratum basale, spinosum and granulosm layers?
Stratum corneum intermediate filaments (tonofilaments)->bundles of tonofilaments->granules combining with bundles to make keratin.
Keratin acts as a barrier to what?
Water, prevents dehydration.
What are three other cell types besides keratinocytes? where are they each found?
- Melanocytes: in basal layer
- Langerham cells: all layers
- Merkel cells: touch receptors in basal layer
Extensions from one melanocyte can touch how many keratinocytes?
36
Langerham cells do what as their function?
move around epidermins, act as first line of defence for the skin.
melanin pigment is found in what cells? these cells are degraded fastest in white type of skin color?
melanocytes
White skin
Eumelanin is what color? Pheomelanin?
brown/black, reddish/yellow
Albinism has what kind of pigment? what enzyme is it lacking? where can this disease have serious consequences?
no pigment. lacks the enzyme that converts tyrosine->DOPA->melanin (enzyme=tyrosinase)
What gives the red tone to our body? what is a common pigment in plants?
oxyhemoglobin
carotenes
Melanin is deposited into which cells? which occurs in which level?
any of the 36 cells that the melanocyte is touching.
stratum basal.
Melanosomes contain what? what do they do?
contain tyrosinase and melanin.
they form a protective ring around the nucleus to prevent UV rays from hitting it.
degradation of what happens more rapidly in white skin than black skin?
melanosomes.
Melanosomes can travel to which layer?
stratum spinosum.
Freckles are due to? Basal cell carcinoma (least malignant of skin cancers) is due to? Squamous cell carcinoma due to? Melanoma (most dangerous)?
hyperpigmentation of melanin
stratum basal cells
keratinocytes in stratum spinosum
cancer of melanocytes
The two layers of dermis are?
- papillary layer: upper closest to dermis
2. Reticular layer: lower, dense irregular ct
hypodermis located where? lots of what kind of tissue?
below dermis
adipose.
Stratum spinosum/basale layers are considered what type of dermis? whcih is located where relative to dermis? What is below dermis?
Epidermis
Above
Hypodermis
Marfans syndrome has the absence of which protein? which interacts with what other two proteins? appearence? issue it causes with the eye?
fibrilin
interacts with elastin and collagen
person appears very tall, limbs abnormally long etc.
causes lens to move forward, defective suspensory fibres.
What are two examples of exocrine glands?
oil glands (connected to hair follicles) and sweat glands.
What is characteristic of the oil glands? what kind of secretion does it use? what kind of duct/secretory structure?
“bags of white cells” around gland.
holocrine.
simple branched acinar.
Sweat glands have what sort of shape? what is the structure of duct and secretory system? how many of them roughly? gland has what type of cells? duct has what type of cells? type of cells around secretory portion? how much sweat do we excrete? most of gland is always present where? some also located where?
coiled, coil up through epidermis to surface. simple coiled tubular 3-4 million gland= simple cuboid duct= stratified cuboid secretory= stratified columnar 1L a day. always in dermis, some in hypodermis.
myoepithelial cells surround which portion of the sweat gland?
secretory portion.
is there blood supply in the epidermis? where?
NO, only in dermis/hypodermis.
What are three types of neural receptors? where are they each located?
- free nerve endings (go into epidermis, have touch receptors)
- Pacinian: very large, in hypodermis, detect deep pressure
- Meissner: only located in papillae (dermis), has 1-2 spiral axons
What is the thinnest skin in the body? is the conjunctiva continuous with the thin skin?
Eyelids
YES
Glands on the eyelids are called? What two different kinds are there? Orientation of them? How many?
Melbomian glands
Superior (on upper lid) and inferior (on lower lid)
They run vertical down lid
30-40 superior and 20-30 inferior
What is a Zeis gland? where is it located?
type of oil gland, much smaller than other oil glands. located in the eye, near hair follicle.
Conjunctiva is what kind of epithelium? the inner eyelid has what type of conjunctiva? globe (cornea) has what kind? Conjunctiva is continuous with what tissue?
mucin secreting columnar epithelium
palpebral
bulbar
cornea epithelium
Conjunctiva turns around at the fornix and becomes what type of tissue?
epithelium.
Which type of conjuntiva is curvier in appearance?
Palpebral (compared to bulbar)
Where is the primary source of O2 located for cornea? tear also provides what in terms of surface? other major functions?
tear film.
smooth refractive surface
allows for hydration and lubrication
What are the three layers of the tear film?
- oily layer (outer): thin layer made by melbomian glands
- water/aqeous layer: thickest, made by lacrimal/accessory lacrimal glands
- Mucous layer: secreted by goblet cells of conjunctiva, thinnest layer.
Sty is an infection of what?
eyelash follicle, Zeis or Tarsal (melbomian) gland.
Vitiligo is a disorder of?
skin, dissapperance of melanocytes
Psoriasis is what type of disorder?
skin increase in # of proliferating cells, decrease in life span, forms flaky patches on skin.
