9/9a Integument Histology Lab Flashcards
how can you identify simple squamous epithelium on a slide?
it is 1 layer and the shape is squamous because the nucleus is slightly squished
where do you find simple squamous epithelium
in the alveoli of the lungs and the heart lumen
What type of tissue looks like it has multiple layers, but actually doesn’t?
pseudostratified columnar
Does each cell touch the basement membrane of the a pseudostratified columnar tissue?
all cells touch the basal membrane, but not all reach the surface (apical)
Layer the integument
epidermis
dermis
hypodermis
how do you ID strata within the epidermis?
S corneum - thick-ish space with keratinocytes that don’t have nuclei
S lucidum - only seen on thick skin, it will appear as a white thin layer
S Granulosum - will be a transition layer between spinosum and corneum/lucidum. loose nuclei
S Spinosum - will have spiral looking white lights within it and langerhan cells
S Basal - will be a thin layer of melanocytes right next to the papillary layer
what type of epithelium is the epidermis?
highly keratinized
stratified squamous
lots of keratinocytes
the proteins are able to withstand lots of tensile stresses and tears
what specialized cell is seen in the stratum basale?
melanocytes
what types of CT fibers are found in great abundance in the reticular layer of the dermis?
Type I Collagen
- good at resisting stress
- Dense IRREGULAR tissue - collagen is NOT lined up regularly because skin needs to function under different tension and stressors
3 types of cell junctions in the epidermis
- tight junction - granulosum, helps prevent water loss
- desmosome - spinosum, helps maintain structure and helps with abrasion
- integrins - basale, help with commnication
what is the papillary layer?
it is within the dermis, has tactile sensory for pressure and vibration, has meissner’s corpuscles
what are pacinian’s corpuscles?
found in the hypodermis, are sensory to pressure and vibration that is deep
hypertrophic scar components
- wound is maintained in margins, but appears stretched and raised
- started by presence of an infection
- associated with excessive tension
- the reticular layer grows in abundance of CT and less type 1 collagen arrays in a hypertrophic scar
keloid scar
- overgrowth of scar beyond wound margins
- started by presence of infection
- associated withe excessive tension
where do stem cells come from for new skin generation?
- stratum basale -stem cells
- epidermal derivatives create stem cells (sebaceous glands, hair follicles, and sweat glands)
- dermis has fibroblasts that are a source for wound repair
