Histology 2 Flashcards
Layers of the skin:
Epidermis, Dermis (reticular and papillary layer), hypodermis (superficial fascia),
what do the dermal papillae protect against?
Shearing forces on the skin.
What are the appendages of the skin?
sebaceous sweat gland, arrector pili muscle, eccine sweat gland
What are the layers of the epidermis?
stratum corneum, stratum granulosum, stratum spinosum, stratum basale/germinativum. thick skin also has a stratum lucidum
what are squames?
dead keratin flakes on the outside of stratum corneum.
why is it called the strautum granulosum?
It has a granular appearance due to a lot of high molecular weight keratin
Whats going on in the spinous layer?
In the transition from rounder basal cells, there are intermediate filaments called cytokeratins that are produced. These proteins begin to squamate the cells. Desmosomes are made, and this layer is watertight.
Where are pigmented melanocytes found?
in the stratum basale/germinativum base
whats the stratum basale/germinativum?
Stem cells that replenish the upper layers
MART-1
stains melanocytes
What is the difference between eccrine and apocrine? what type of epithelium do they have around them?
apocrine glands erlease pheromones, and are found in the breast, armpit, ears etc. mammary glands are earwax producers are just modified apocrine glands. ecrine are responisble for thermoregulation.
what are holocrine glands?
sebaceous glands are holocrine glands, it basically means they burst open to extrude their contents.
histology of the nail
The nail bed, sterile matrix, germinal matrix, hyponychium, perionychium, eponychium, oncomycosis, the nail matrix, sub-ungal hematoma. lunula
The structure of connective tissue consists of two components:
- non-cellular extracellular matrix, made up of ground substance(glycosaminoglycans like hyaluronic acid) and fibres(collagen and elastic fibres– elastin and fibrillin)
- cells (fibroblasts, bone or cartilage, and immune cells).
two other names for dermis
lamina propria and stroma
mutations in fibrillin are associated with:
marfan syndrome
what are fibroblasts?
these are pluripotent cells that go on to make chondrocytes in bone, adipocytes, osteoblasts, smooth muscle etc. makes up the cell part of connective tissue.
Basic hemopoiesis
pluripotent stem cells go to be either lymphoid or myeloid stem cells. lymphoid make T and B cells, and myeloid go on to make eosinophils, basophils, monocytes and neutrophils (and erythrocytes)
Basic hemopoiesis
pluripotent stem cells go to be either lymphoid or myeloid stem cells. lymphoid make T and B cells, and myeloid go on to make eosinophils, basophils, monocytes and neutrophils (and erythrocytes) and megakaryocytes.
Granulocytes
granules are revealed by the wright stain. eosinophils (red eosin stain) basophils (methylene blue) neutrophils are neutral. multilobed and complex nuclei
Agranulocytes
lymphocytes with a large darkly staine dnucleus, or monocytes that have a C shaped nucleus and are not to be confused with neutrophils
differences between thick and thin skin
Thin skin: thicker dermis, no stratum lucidum, papillae are not as pronounced as in thicker skin. thick skin has more epidermis.
cardiac muscle vs skeletal vs smooth muscle
cardiac muscle and skeletal muscle are straited, but only cardiac muscle has intercalated disks. smooth muscle has no striations.
What are the types of connective tissue
cartilage, bone, adipose, blood, lymphatic, eleastic and fibrous
What are the 4 basic tissue types
muscle, connective tissue, epithelium, and neural tissue
