Tissues

a group of cells with a common embryonic origin performing a similar function

4 types of tissue

epithelial=skin, covers body surfaces

connective= protects, and supports the body

muscular= produces force

nervous= conducts electrical impulses

epithelial tissue

tightly packed cells, little/no intercellular space, avascular, contains basement membranes

layers of cells (epithelial)

simple, stratified, and pseudostradified

simple epithelium

single layer of cells

absorption and filtration

minimal wear and tear

stratified epithelium

cells stacked in several layers

high degree of abrasion (wear and tear)

pseudostratified epithelium

only one layer of cells, but looks like multiple. not all cells reach the free surface, many have cilia and mucous.

shapes of cells

squamous

cuboidal

columnar

transitional

squamous

flattened or scale like cells

cuboidal

box or cube shaped

columnar

longer than wide

transitional

combination of other shapes, can be found where structures can change shapes, very elastic and extensible

endocrine glands

ductless glands, secretion diffuses into the blood, found in the pituitary, thyroid, and adrenal glands, and the pancreas.

exocrine glands

secretes products into ducts, may enter at the surface or line the covering of the epithelium. found in sweat and salivary glands

mucous membrane

lines structure with opening to the external environment, epithelial layer secretes mucous. lines respiratory, gastrointestinal, urinary, and reproductive tracts.

serous membrane

lines body cavities that don't open to the external environment, consists of 2 layers (visceral and parietal)

cutaneous membrane

the skin

synovial membrane

contains no epithelial tissue, lines cavities of freely moving joints. lubricates and nourishes hyaline cartilage

connective tissue

most abundant in body, tissue that binds and supports

loose connective tissue

also called areolar connective tissue, loosely woven arrangement of fibers. found in mucous membranes, around blood vessels/nerves and body organs

adipose tissue

loose connective tissue that contains adipocytes. fat droplets= triglycerides, major energy reserve

cartilage

avascular, can withstand tremendous force

types of cartilage

hyaline (articular)

fibrocartilage

elastic

hyaline cartilage

most abundant, bluish white in appearance, reduces friction at joints. found at ends of long bones, ribs, embryonic skeleton.

fibrocartilage

main purpose is shock absorbtion, more elastic than hyaline. found in invertebral discs, menisci of knee, epiglottis

elastic cartilage

structural, provides rigidity/strength, maintains shape of some organs. found in the larynx, ear, trachea, Eustachian tubes, nose.

dense fibrous tissue

composed of a close packed matrix of collagen fibers and fibroblasts that are either in regular or irregular arrangement

dense connective tissue (regular)

adapted for tension in one direction, arranged in parallel fashion. found in tendons, aponeuroses, and ligaments.

dense connective tissue (irregular)

found where multi-directional forces are found. located in most fascia, reticular region of skin.

elastic connective tissue

freely branching fibers, provides strength/stretch but snap back to position when stretched. yellowish in color, found in trachea, bronchi, lungs, and vocal chords.

reticular connective tissue

contains a special type of reticular fiber, found in framework of organs, liver, spleen, binds smooth muscle

vascular tissue

blood. made up of plasma, red blood cells, white blood cells, and platelets.

osseus tissue

maintained by special cells, two types (compact and spongy)

muscle tissue

made of muscle cells, highly specialized, converts chemical energy into mechanical energy, 3 types (skeletal, cardiac, and smooth)

nervous tissue

highly specialized and sensitive tissue. capable of converting stimulus to nervous impulses. transmits to other neurons, glands, and muscle fibers

nerve cells (neurons)

made up of the cell body, axons, and dendrites