CSAD 234 Cells, Tissues, and Tissue Aggregates

for exam 1

organization level

cells make up tissues, tissues make up organs, organs make up organ systems

the building blocks of the body

cells and tissues

kinds of tissues

epithelial, connective, muscular, and nervous

cells

basic unit of all the body’s tissues; highly organized masses of protoplasm; unusually small; measured in microns

micron

one-thousandth of a millimeter

tissues

colonies of cells and their intercellular substances combined to exhibit “functional unity”

epithelial tissue

arranged in mosaics; form sheets of tissue that cover the external surfaces of the body; line the internal cavities and passages leading toward the exterior of the body

types of epithelial tissue

simple cuboidal, simple squamous, simple columnar, and stratified squamous

squamous

“to squish”

simple tissue

one layer

stratified tissue

multiple layers

connective tissue

extensively distributed throughout the body; binds parts together while allowing considerable movement between structures

types of connective tissue

dense, adipose, areolar, compact bone, and blood

adipose tissue

fat

areolar tissue

holds organs in place and attaches epithelial tissue to other underlying tissues

blood

connective tissue that moves through the body

muscle tissue

principle mediator of all movements; has contractile properties and an elongated cell nature; 40% of body weight; all voluntary behavior and some involuntary

types of muscle tissue

skeletal, cardiac, and smooth

skeletal muscle

moves or stabilizes the position of the skeleton; generates heat; protects internal organs; guards entrances and exits to many tracts; striated, tubular, and multinucleated

cardiac muscle

moves blood and maintains blood pressure; non-striated, spindle-shaped, uninucleated

smooth muscle

moves food, urine, and reproductive tract secretions; controls diameter of respiratory passageways and blood vessels; striated, branched, and uninucleated

nervous tissue

group of highly specialized cells; respond to abrupt environmental changes by modifying their electrochemical composition

tissue aggregates

organs, specific muscles, fascia, tendons, and ligaments

organs

tissues that all serve a specific functional purpose (e.g., liver)

specific muscles

muscle tissues that serve an anatomical region (e.g., bicep)

fascia

thin sheath of fibrous tissue that encloses a muscle; membrane that surrounds multiple tissues together

ligaments

connects “like to like” (2 organs or 2 bones/cartilage); a fibrous connective tissue; stabilize joints while also allowing mobility; non-contractile; have sensory nerves that transmit info about joint position to the brain

tendons

strong, fibrous collagen tissues that attach muscles to bones/cartilage; transmit forces produced by muscles; have sensory nerves that transmit info about muscle tension and joint position