Tissue Level

tissue

coordinated community of specialized cells that share structure and function

epithelial tissue

forms protective barriers and coverings

connective tissue

provides support and structure; connects and binds tissues and organs

muscle tissue

responsible for movement and generating force

nervous

transmit signals and coordinate the body’s activities

2 types of epitheilial tissue

glandular epithelium and covering/lining epithelium

glandular epithelium

composed of cells specialized for process of secretion; composed of glands

glands

anatomical structures that synthesize and discharge products onto a surface or into the bloodstream

covering/lining epithelium

widely distributed; avascular (lacking blood vessels) but has nerve cells

simple epithelium

single cell layer for absorption and filtration

stratified epithelium

multiple layes for portection against friction and stress

epithelium

surface covering

endothelium

epithelial lining of blood and lymphatic vessels

mesothelium

epithelial lining of body cavities

two distinct cell surfaces

basal surface and apical surface

basal surface attachs to…

basement membrane

apical surface faces…

lumen or external environment

cuboidal epithelium

cubed shaped cells

squamous epithelium

flattened and scale like, forming a tightly packed barrier

columnar epithelium

tall, column-shaped cells

psuedostratified columnar epithelium

upper respiratory tract; appear similar to stratified epithelia, but actually columnar

stratified squamous

multiple layers of flattened cells protect against abrasion and water loss

keratinized

outer layer of skin; dead

non-keratinized

several box-shaped cell layers; glandular tissues

stratified cuboidal

several boxed shaped cell layers; glandular tissues

stratified columnar

rarest type; multiple layers of tall cells; specific locations

simple columnar

tall column shaped cells with round or oval nuclei; great at secretion and absorption

simple squamous

single layer of flattened scale-like cells with centrally located nuclei; minimal resistance to diffusion of gases or fluids

simple cuboidal

single layer of cube shaped cells; found where secretion and absorption are crucial

basement membrane

non-cellular, thin, specialized sheet of extracellular matrix

composition of basement membrane

structural proteins and glycoproteins

zones of basement membrane

basal lamina and reticular lamina

basal lamina

directly beneath epithelial cells

reticular lamina

connects basal laminate to underlying connective tissue; contains anchoring fibrils made mostly of type four collagen that extends into connective tissue to stablize entire structure

lamina lucida

located beneath epithelial plasma membrane; lighter under electron microscrope; rich in laminins and proteoglycons

laminins

glycoproteins that help cells adhere

proteoglycons

molecules that provide hydration and resilience

what secures epithelium to basement membrane

hemidesmosomes and tonofilaments

extracellular matrix

network of molecules located outside of cells providing structural support and biochemical signals to surrounding cells; not made of cells but proteins, glycoproteins, and polysaccharides

ground substance

major part is glycosaminoglycans (GAGs): long chains of sugars with negative charges

common types of GAGs

hyaluronic acid, chondroitin sulfate, and nephron sulfate

elastic fibers

composed of elastin; long thin branching fibers forming networks allowing tissues to stretch and recoil

reticular fibers

delicate branching fibers made of collagen type iii that create a supportive network forming structural framework in soft tissue

collagen fibers

most abundant and strongest fiber type; provide tensile strength and resistance to stretching

“blast” cells

immature, metabolically active cells that secrete and build ECM

“cyte” cells

mature, less active forms of cells that maintain ECM

proper loose areolar

mix of all three fiber types found widely throughout the body

proper dense elastic

high proportion of elastic fibers alongside collagen fibers; allow tissue to stretch and recoil after deformation

proper dense irregular

high density of collagen fibers but disorganized and interwoven; overall strength and stability in multiple directions with a degree of flex

proper dense regular

high density of collagen in parallell bundles; exceptional strength and ability to resist pulling forces in a specific direction

proper loose reticular

network of reticular cells, specialized fibroblasts, and lymphocytes from storm of essential immure organs

adipose tissue

primarily adipocytes; low portion of fibers and ground substance; distributed throughout body for insulation, protection, and energy

what do body membranes regulate

epithelial layer and connective tissue layer

muscous membrane

line body cavities that open to the outside world; top layer produces mucus that traps and prevents materials from entering body and surfaces moist

serous membrane

line body cavities closed to exterior like the heart, secrete a watey lubricant and the name is based on the location

cutaneous membrane

outermost layer that acts as a barrier; dry and the thickest

synovial membrane

line inner surfaces of joints and bursae; produce lubricant that reduces friction b/w bones during movement and is a cushion or impact

simple tubular

straight, tube-like secretory unit that opens directly onto epithelial surface

simple branched tubular

several tubular secretory units share a single unbranched duct

simple coiled tubular

tubular secretory unit is coiled but still only has 1 duct

simple acinar gland (alveolar)

rounded, sac like shape with single small duct

simple branched acinar gland

multiple sac-like secretory units empty into 1 duct

compound tubular gland

secretory units are compound and tube shaped and multiple connect to branching duct system

compound acinar gland

sac like and organized into branching duct system

compound tuboacinar gland

tubular and acinar units into branched duct system

merocine glands

release through exocytosis (sweat and salivary glands)

holocrine glands

rupture