Decussation
Encyclopedia
Decussation is used in biological contexts to describe a crossing.
Examples include:
Examples include:
- In the brainBrainThe brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
, where nerve fibers obliquely cross from one lateral part to the other, that is to say they cross at a level other than their origin. See Decussation of the pyramidsDecussation of the pyramidsThe two pyramids contain the motor fibers that pass from the brain to the medulla oblongata and medulla spinalis, corticobulbar and corticospinal fibers....
. - In phyllotaxisPhyllotaxisIn botany, phyllotaxis or phyllotaxy is the arrangement of leaves on a plant stem .- Pattern structure :...
when an opposite pattern of leaves has successive leaf pairs that are perpendicular, it is called decussate. - In tooth enamelTooth enamelTooth enamel, along with dentin, cementum, and dental pulp is one of the four major tissues that make up the tooth in vertebrates. It is the hardest and most highly mineralized substance in the human body. Tooth enamel is also found in the dermal denticles of sharks...
, where bundles of rods (rods are the basic structural unit of enamel) cross each other as they travel from the enamel-dentine junction to the outer enamel surface (or near to it).