Histology: Integument, Soft CT, Hard CT Flashcards
What are the 4 basic tissue types?
Epithelial, connective, muscle, and nervous
What is the difference between gap junctions and tight junctions?
Gap junctions connect the cytoplasm of two adjacent cells, and tight junctions seal the space above and below the epithelium.
Name each layer
From bottom to top, stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum
What kind of tissue is this?
Lung epithelium
What kind of tissue is this?
Gut epithelium
What are the 5 functions of the epithelia?
physical protection, controls transport, move fluids across surfaces, produce speacial secretions, sensory functions
Name these types of exocrine glands
Top row: simple tubular, simple branches tubular, simple coiled tubular, simple acinar, simple branched acinar
Bottom row: compound tubular, compound acinar, compound tubulo-acinar
Name the mechanisms of secretion and explain them each
From left to right: merocine (release via excytocis), apocrine (cells release portions of themselves), holocrine (the entire cell distintergrates)
Name the functions of the layers of the epidermis: stratum basale, stratum spinsosum, stratum granulosum, stratum lucidum, stratum corneum
Stratum basale: where cell divison (mitosis) takes place
Stratum spinosum: responsible for the skin strength and flexibility, and they look spiny due to demosomes connecting the cells. When dehydration occurs, the cells look as though they have spikes
Stratum granulosum: helps form a waterproof barrier. the granules are due to the keratin structures in them
Stratum lucidum: it is responsible for the skins ability to stretch, it looks translucent (no nuclei), continues to provide a barrier to water
Stratum Corneum: they are sort of like pancakes that are waterproof, they prevent unwanted things from entering, and they prevent water loss
What is the difference between cornification and keratinization?
Cornification: braod term describing the formation of the horny layer of the epidermis
Keratinization: when the keratinocytes in the epidermis mature and here is polymerization of cytokeratin and undergo apoptosis to create the stratum corneum
What are melanocytes and where are they located?
They are the cells in the epidermis that produce melanin (skin pigment). They are located in the stratum basale.
What is a merkel cell and where are they located?
They are somatosensory cells that lie in the stratum basale and connect to the dermis (blood supply)
What are langerhans cells and where are they found?
They are immune cells that lie in the stratum spinosum.
What do arrector pili muscles for?
When they contract, the hairs stand on end (straight up).
Name the lettered structures.
A: Sebaceous gland
B: Hair bulb
C/D: Arrector pili
E: Sweat gland
What is this structure?
Sweat glans (Eccrine)
What are 6 functions of the integument?
- Protection against mechanical forces
- Waterproofing
- Keep unwanted things out
- Sensory
- Temperature control
- Raidiation barrier (Uv rays)
What types of forces does connective tissue need to deal with?
Tensile (rope pull) and compressive (squishing)
What molecule functions as the “rope” and what molecule functions as the “sponge”?
Collagen is our rope, hylauronic acid is our sponge
What are the big molecules that absorb water in connective tissues?
Proteoglycans