first half of chapter 3

How many primary tissue classifications

4; epithelial tissue, connective tissue, nervous tissue, muscular tissue

what is Epithelial Tissue

Tissue composed of closely spaced cells that cover organ surfaces or form glands

what is epithelial tissues function

serve for protection, secretion, and absorption

Where are epithelial tissues located

Epidermis, inner lining of digestive tract, liver, other glands

what is connective tissue

tissue with usually more matrix than cell volume

what is the fucntion of connective tissue

often specialized to support, bind, and protect organs

locatioj of connetcive tissue

tendons, ligaments, cartilage, bone blood, lymph

What is nervous tissue

tissue containing excitable cells specialized for rapid transmission of information to other cells

nervous tissue location

Brain, spinal cord, nerves

what is Muscular tissue

tissue composed of elongated excitable cells specialized for contraction

Location of muscilar tissue

skeletal muscles, heart / cardiac muscle , walls of viscera / smooth muscle.

muscular tissue

nervous tissue

connective tissue

epithelial tissue

characteristics of epithelial tissue

one or more layers, closely adhered cells, form surfaces, avascular(no blood vessels), anchored to basement membrane, has basal and apical surfaces

simple epithelium characteristics

every cell is on basement membrane

types of simple epithelium

simple squamous, simple cuboidal, simple columnar, pseudostratified calumnar (rare)

Stratified epithelium characteristics

two or more layers, named by shape of top layer

types of stratified epithelium

stratified squamous, stratified cuboidal, urotherlium (transitional epithelium)

simple squamous appearance

single layer of thin cells, fried egg shape, flattened nucleus, thin hard to see cytoplasm, have angular contours in surface views

locations of simple squamous epithelium

Air sacs called alveoli (lungs), glomerular capsules of kidneys, kidney tubules, inner lining of heart (endothelium), serous membranes of stomach, intestines, pericardium, peritonium, mesentries, surface mesothelium of pleurae

functions of simple squamous epithelium

allows rapid diffusion or transport of substances theough membranes; secrets lubricating serous fluid

simple cuboidal epithelium appearance

single layer of square or round cells; in glands, often pyramidal and arranged like segments of a orange, central nuclei, brush border of microvilli in some kidney tubules, ciliated when in bronchioles of lung

simple cuboidal locations

liver, thyroid, mammary and salivary glands, most kindey tubules, bronchioles

Functions of simple cuboidal epithelium

absorption, secretion, production and movement of respiratory mucus

simple columnar appearance

single layer of tall narrow cells, sausage shape nuclei usually in basal half of cell, apical portion shows secretory vessicles, shows brush border of microvilli, ciliated in some organs, may possess goblet cells

locations of simple columnar

inner linings of stomach, intestines, gallbladder, uterus, uterine tubes, some kidney tubules

functions of simple columnar epithelium

absorption, secretion of mucus and other products, movement of egg and embryo in uterine tube

pseudostratified columnar epithelium appearance

looks multilayered, some cells do not reach free surface, all cells reach basement membrane, nucleus in deeper half of epithelium, often with goblet cells, often ciliated

locations of pseudostratified columnar epithelium

respiratory tract, nasal cavity to bronchi, portions of male urethra

pseudo stratified columnar functions

secrets and propells mucus

keratinized stratified squamous epithelium appearance

multiple cell layers becoming flat and scaly towards surface, covered with a layer of dead compact cells w/o nuclei, basal cells appear cuboidal to columnar

locations of keratinized stratified squamous epithelium

epidermis, palms and soles are especially keratinizes

functions of keratinized startified squamous epithelium

resists abrasion, retards water loss through skin, resists penetration by pathogenic organisms

non keratinized stratified epithelium appearance

same as keratinized but without the surface layer of dead cells

non keratinized stratified squamous epithelium locations

tongue, esophagus, anal canal, vagina

non karatinized stratified squamous epithelium functions

resist abrasions and penetration by pathogenic organisms

stratified cuboidal epithelium appearance

two or more layers of cells; surface cells roughly square or round

stratified cuboidal epithelium locations

sweat glands, ducts, egg producing vesicles / follicles of ovaries, sperm producing ducts (seminiferous tubules) of testes

stratified cuboidal epithelium functions

contributes to sweat secretion, secretes overian hormones, produces sperm

urotherlium/ transitional epithelium appearance

resembles stratified squamous but with rounded buldge cells above the surface, 5-6 cells thick when relaxed, 2-3 cells thick when stretched, cells may be flatter or thinner when uroethelium is stretched, some cells have 2 nuclei

urothelium transitional epithelialium locations

urinary tract- part of kidney, ureter and bladder; part of urethra

urothelium transitional epithelium function

protects underlying tissue from osmotic acidic effects of urine; stretches ro allowe filling of urinary tract

most prevalent tissue in human body

connective tissue

connective tissue functions (in depth)

binding of organs, support, physical protection, immune protection, movemeny, storage, heat production, transport

Fibers of fibrous connective tissue

collagen fibers, reticular fibers, elastic fibers

Collagen fibers:

tough and flexible (white fibers on tendons and ligaments)

Reticular fibers

thin collagen fibers (framework of spleen and lymph nodes)

Elastic fibers

stretch and recoil (elastin protein is abundant in lungs)

Cells of fibrous connective tissue

Fibroblasts/fibrocytes, leukyocytes, adipocytes

Fibroblasts/Fibrocytes

produce fibers and ground substance

leukyocytes

white blood cells (neutrophils, lymphocytes, macrophages, plasma cells) that help body defenses

adipocytes

fat cells

Fibrous connective tissue types

Loose connective tissue, dense regular connective tissue, dense irregular connective tissue, adipose tissue

fibrous connective tissue: Loose connective tissues

Areolar and reticular connective tissues

Areolar connective tissue

Abundant, binds epithelia to deeper tissue, is considered one classification of what is called fascia

Areolar connective tissue appearance

loose arrangements of collagenous and elastic fibers, scattered various cell types, abundant ground substance and numerous blood vessels

Areolar connective tissue locations

underlying nearly all epithelia, surrounds blood vessels, nerves, esophagus, trachea, fasciae between muscles, mesentries, visceral layers of pericardium snd pleura

areolar connective tissue functions

loosely bind epithelia to deeper tissues, allows passage of nerves and blood vessels through other tissues, provides arena for immune defense, provides waste removal for overlying epithelia

Reticular connective tissue appearance

loose network of reticular fibers and cells, infiltrated with numeroud lymphocytes and other blood vessels

Reticular connective tissue locations

lymph nodes, spleen, thymus, bone marrow

reticular connective tissue functions

support stroma (framework) for lymphatic organs

what is Dense regular connective tissue

highly organized, mostly collagen fibers, many fibroblasts, tendons and ligaments, considered the other classification of what is called fascia

dense regular connective tissue locations

tendons and ligaments

dense regular connective tissue functions

when in ligaments, they tightly bind bones together and resist stress, tendons attach muscle to bone and move the bones when the muscles contract

dense regular connective tissue functions

when in ligaments, they tightly bind bones together and resist stress, tendons attach muscle to bone and move the bones when the muscles contract

what is dense IRREGULAR connective tissue

random arrangement of collagen fibers, resist stress, are most of the dermis in skin, have protective capsules

Dense irregular connective tissue appearance

densly packed collagen fibers running in random directions, few visible cells, long fibers in the tissue appear as short

chopped up pieces in thin histological sections

Dense irregular connective tissue locations

deeper portions of dermis, capsules around viscera (liver, kidney, spleen); fibrous sheathes around muscles, nerves, cartilages, and bones

Dense irregular connective tissue functions

dursble, hard to tear, variable orientations of fibers withstand stress applied in all directions

what does Adipose tissue (fat cells) do, what is it

stores energy and provides protection - white fat vs brown fat

adipose tissue appearance

dominated by adipocytes, large empty cells with thin margins and nuclei pressed against the inside of the plasma membrane, often appear pale bc of scarcity of stained cytoplasm; blood vessels often visible

adipose tissue locations

subcutaneous fat beneath skin; breast; heart surface; mesentries; surrounding organs like kidneys and eyes

adipose tissue functions

energy storage, thermal insulation, heat production by brown fat, cushioning for some organs, fills space, shapes body