• thin sheet of specialized extracellular matrix
• composed of mostly protein

Appears stratified

single layer

• like buttons or rivets
• hold cells tightly together at specific points but do not block the movement of substances between the cells.

• formed of a band of proteins that fuse together the cell membranes of neighboring cells
• create a waterproof seal between two cells, forming an impenetrable wall to prevent substances from moving between the cells

• connects neighboring cells, not to seal or bind them but to serve a means of communication
• special protein tunnels between neighboring cells
• small particles, such as ions, can pass from one cell to another through them to relay messages without entering the extracellular fluid

• ductless, solid masses of epithelial cells
• they secrete their products (hormones) into tiny blood vessels; no duct is involved. 

• consists of two components- an amorphous (structureless) ground substance and fibers

• composed of water, minerals, and small glycoproteins
• both connective tissue cells and the fibers they synthesize are embedded within it
• has a sticky character that holds the cells and fibers together
• can be liquid, gelatinous, rubbery, or rock-hard

• protein
• withstands the high tension of musculoskeletal movements

• woven into elastic fibers (thin, branching filaments)
• weak
• can stretch easily and recoil like a spring to resume their original shape and length
• vocal cords

• make two types of protein: collagen and elastin
• makes fibers

• connective tissue
• stores energy in he form of triglycerides
• accumulate so much fat that they crowd out other cells and the extracellular matrix

• composed of cartilage tissue, which contains cartilage cells, varying amounts of collages and elastin fibers, and a rubbery ground substance that imparts springy resiliency and keeps it lubricated
• firm and somewhat flexible but not as hard as bone.
• designed to yield to force and return to its normal shape
• provides cushioning for joints and shape to certain structures