Study sets, textbooks, questions
Upgrade to remove ads
ILA 02 - Normal Skin Histology
Based off of https://www.youtube.com/watch?v=yQQ2Dmz42Vs.
Terms in this set (29)
1. Stratum corneum.
2. Stratum lucidum.
3. Stratum granulosum.
4. Stratum spinosum.
5. Stratum basale.
What the SEVEN (7) Important Layers of the Skin?
1. Outermost layer of the epidermis, which consists of flattened, keratinized cells (and DEAD cells).
1. Clear, transparent layer of the epidermis under the stratum corneum.
2. Found ONLY in the thick skin of the fingers, palms, and soles.
1. A layer of the epidermis that marks the transition between the deeper, metabolically active strata and the dead cells of the more superficial strata.
Stratum spinosum (Spiny Layer)
1. A layer of the epidermis that provides STRENGTH and FLEXIBILITY to the skin.
1. The deepest layer of the epidermis consisting of stem cells capable of undergoing cell division to form new cells.
1. The inner layer of the two main layers of the skin.
2. The dermis has connective tissue, blood vessels, oil and sweat glands, nerves, hair follicles, and other structures.
3. It is made up of a thin upper layer called the papillary dermis, and a thick lower layer called the reticular dermis.
Hypodermis (Subcutaneous Layer)
1. Also called a subcutaneous layer, this is a layer of FAT located under the dermis of the skin.
2. The hypodermis helps to insulate the body and protects underlying muscles and other structures.
Tattoo Pigment in Skin
What abnormality is seen here?
1. The dermis is BLUE-GREY rather than pink!
2. Dermal collagen has been replaced by elastic fibers due to severe CHRONIC sun exposure.
What is abnormal about this skin?
- Located in the epidermis.
- Play an important role in providing skin structure and in functioning of the immune system.
1. Anchoring junctions that prevents cells subjected to mechanical stress from being pulled apart.
2. Button like thickenings of adjacent plasma membranes connected by fine protein filaments.
What cellular structure do the "spines" between these cells represent?
Seborrheic Keratosis (SK)
1. The keratinocytes are making "horn pseudocysts" filled with keratin.
2. Note how the keratin in these pseudocysts resembles the stratum corneum of normal skin...
Invasive squamous cell carcinoma (SCC)
1. This is a malignant tumor of keratinocytes.
2. The keratinocytes have abundant pink cytoplasm because they are filled with cytokeratin filaments.
3. Tumor cells are trying to produce a keratin like normal keratinocytes do. But instead of creating a nice stratum corneum, the keratin gets swirled up into pink "pearls" surrounded by tumor cells in the dermis.
***Note adjacent normal epidermis (left).
1. Atypical nuclei.
2. Atypical mitotic figures.
3. Keratin "pearls"
What are the histologic features of Squamous Cell Carcinoma (SCC)?
1. Cell in the basal layer that gives color to the skin.
BOTH can have a clearing around the cell.
BUT, melanocytes have cytoplasm hugging the nucleus due to the artifact vacuole being around the outside of the cell.
***melanocytes are usually GREY rather than brown.
How to distinguish between melanocyte and keratinocyte?
Lentigo Simplex (Solar Lentigo)
1. A type of color-containing (pigmented) lesion not caused by sun exposure, which looks like the freckle-like condition (lentigo) caused by sun exposure (solar lentigo).
2. In both conditions, an increased number of pigment-producing cells (melanocytes) are present.
1. This is technically pathologic but is still benign.
2. Remember that pathologic condition just means "not normal" but not necessarily severe or morbid or malignant.
lichen simplex chronicus (LSC)
1. This makes the skin appear as acral (palm/sole) skin due to the chronic rubbing, scratching, picking, or itching.
2. Chronic irritation causes hyperplasia of epidermis in attempt to protect skin from injury.
--> Makes epidermis resemble acral skin.
Collagen Type I is the MAIN component of the reticular dermis.
1. Collagen bundles (dense connective tissue).
2. Smooth muscle (arrector pili).
What are THREE things that form pink bundles in the dermis?
1. Numerous small white vacuoles in cytoplasm represent lipid droplets.
2. Oil-secreting gland in the dermis that is associated with hair follicles.
1. glands that produce sweat; found over most of the body.
1. Gland/duct/cyst (lined by epithelium).
2. Vessel (lined by endothelium).
3. Artifact (lined by nothing).
When you see a white/empty space on an H&E tissue section, there are THREE general options for what it might be.
What are they?
Blood vessel in the dermis.
- Lined by endothelium (single layer). Sometimes you can see red blood cells in the lumen.
1. Sweat glands in the pubic and underarm areas that secrete thicker sweat.
2. Also, that produce odor when they come in contact with bacteria on the skin.
Meissner (tactile) corpuscle.
1. Looks like a striped Easter egg or a bunch of pink cotton candy at the fair.
--> Fine touch.
--> That's why it is just below the epidermis.
--> Close to skin surface so it can pick up very subtle delicate touch.
Pacinian (lamellar) corpuscles
1. Big onions in deep dermis/subcutis, usually on volar extremities (particularly near palms/soles).
--> deep pressure and vibration.
Sets found in the same folder
ILA 01 - Fungal Skin Infections
LEC 01 - Melanocytic Lesions
LEC 02 - Vascular Lesions: Malformation…
LEC 03 - Dermatologic Inflammation
Other sets by this creator
PI #1 - Clinical Dermatology
LEC 10 - Pediatric Dermatology
LEC 09 - Common Non-Melanocytic Cutaneou…
LEC 08 - Syndromes & Genetic Disorders w…