Appendage
An appendage (or outgrowth) is an external body part, or natural prolongation, that protrudes from an organism's or microorganism's body.
Types in animals
In
In
]Appendages may become uniramous, as in insects and centipedes, where each appendage comprises a single series of segments, or it may be biramous, as in many crustaceans, where each appendage branches into two sections. Triramous (branching into three) appendages are also possible.[1]
All arthropod appendages are variations of the same basic structure (homologous), and which structure is produced is controlled by "homeobox" genes. Changes to these genes have allowed scientists to produce animals (chiefly Drosophila melanogaster) with modified appendages, such as legs instead of antennae.[2]
Types in prokaryotes
A number of cell surface appendages are found in
Archaea
A number of surface appendages may be present on different archaea. Two types of appendage are species-specific;
Archaella are the similar structures to bacterial flagella with the same function in motility particularly swimming, but with a different composition and action. Pili are used in attachment to surfaces, possible communication between cells enabling cell to cell contact allowing genetic transfer, and the formation of
Bacteria
Bacterial surface appendages include
Types in plants
A leaf is the main appendage of a plant stem. Prosthechea is a genus of orchids named for the prostheca appendage on the back of the column. Hair like structures known as trichomes are found on many types of plants.