describe spot desmosome.
spot desmosome ties adjacent cells togethr using cell adhesion molecules (CAMs)
what is pseudostratified ciliated columnar epithelium? and what are its fuctions? give an example
cells that go from basement membrane to apical. It's function is protection, secretion, and movement of mucus with cilia
what is trasitional epithlium?
permits expansion and recoil after stretching; an example is the urinary bladder
what are simple squamous epithelium used for and give a few examples.
reduces friction, controls vessel permeability (allows for gas exchange) performs absorption and secretion. Lining of blood vessels and heart
what are simple cuboidal epithelium used for?
limited protection, secretion, and absorption. Located in the glands, ducts and portions of kidney tubles, thyroid gland.
what are simple columnar epithelium?
portection, secretion, absorption, prevent avids to go all the way through stomach. found in the lining of stomach, intestine, gallbladder
what are endocrine glands
release hormones into inerstitial fluid and plasma without ducts
produce secretions onton epithelial surfaces through ducts. Exocrine glands cna be either unicellular or multicelluar
what are some types of exocrine secretions?
- serous glands: produce watery secretions
- mucous glands: secrete mucins
- mixed exocrine glands: secrete both serous and mucous products
produced in Golgi apparatus and vesicles released by exocytosis, cells are in tact after secretion. examples are saliva from salivary glands, mucus in digestive/respiratory tracks/perspiration
what are apocrine secretion?
- secretions produced in Golgi apparatus, released by shedding cytoplasm with secretory product. Cell remains in tact and regrows.
- Ex. Milk from mammary glands, underarm perspiration
what are holocrine secretions?
- secretion occurs through loss of entire cell, killing gland ells
- gland cells replaced by stem cells
- ex. skill oils and ewaxy coating of har (from sebaceous glands)
- cell division replaces lost cells, cells produce secretion, increasing in size, cells burst, releasing cytoplasmic contents
what are the basic components of connective tissues?
- specialized cells
- solid extracellular protein fibers
- fluid extracellular ground substance
what do connective tissues do?
- support and protection (supporting connective tissue)
- transportation of materials (fluid connective tissues)
- storage of energy reserves (fats)
- defense of the body (immune system)
Name the different types of connective tissue proper.
- fat cells (adiopocytes)
- mast cells
what are fibroblasts
most abundant cell type; produce connective tissue fibers and ground substance
scattered throughout matrix; phagocytize damaged cells or pathogens that enter the tissue, release chemicals that mobilize the immune system
fat cells (adipocytes)
- permanent residents
- number of fat cells vary
- small, mobile cells often found near blood vessels
- cytoplasm is packed with vesicles; filled with chemicals that are released to begin body's defensive activities after an injury or infection
what are the basic types of connective tissue fibers?
- collagen fibers (most common) long straight unbranched, strong but flexible
- elastic fibers: branched and wavy; after stretching they retun to their orig length. Contain protein elastin
- reticular fibers: made of same protein subunits as collagen, but arranged differently, thinner than collagen fibers, form branching interwoven framework