Dandruff (morphology)
Fish scales ( roach )
In morphology , the theory of the shape of living beings , flake or plate-shaped elements are referred to as scales ( Latin squama ) .
In zoology and human biology
Appendages
Snake scales ( grass snake )
Dandruff is a common part of the body shell (integument) in various animals. In vertebrates , these and the other skin appendages are dermal or epidermal derivatives of the skin and are anchored in it.
- The placoid scale covers the skin of the cartilaginous fish as a skin tooth .
- Different groups of bony fish have developed characteristic scale types :
- In the bony elasmoid scale of the real bony fish , the more original cycloid scale and the ctenoid scale are differentiated. In the rhomboid ganoid scale of the primeval ray fins , the bone base is still covered with a thick, shiny layer of hard ganoin .
- The cosmoid scale covers the skin of the meat-fin fish .
- The horny scale is found on the entire skin surface of reptiles , such as snakes . Especially in the Schuppenkriechtieren it is of taxonomic importance ( Pholidose ). It also occurs on the bird's leg, on the tail of many rodents and some insectivores .
- The wings of the butterflies are covered with scales .
Dander of the human skin
The skin flake is an aggregation of corneocytes that is visible to the naked eye . The outer layer of the keratinized squamous epithelium , which generally forms the multilayered epidermis (upper skin) of the vertebrates, detaches itself from the layers below in the course of desquamation (peeling).
Bones of the skull
- The temporal bone scale ( pars squamosa ) of the temporal bone lies on the side of the skull above the external auditory canal .
- The frontal bone scale ( Squama frontalis ) is part of the frontal bone . It forms the upper edge of the eye socket , the supraorbital margin .
- The occipital scale ( Squama occipitalis ) of the three-part occiput forms the posterior edge of the foramen magnum (occipital hole).
In botany
- The scale is a flat appendage of the plant epidermis (transformed plant hair ).
- It is the lower leaf of some seedlings, trees, herbs and sprouts.
- The cone flower of the cones (botany) has cover scale and seed scale.
- Softwood cones have a cone scale.
- Sucker scale in bromeliads.
See also
Individual evidence
- ↑ a b c Hynek Burda : General Zoology . Eugene Ulmer. Stuttgart 2005. pp. 159-161.
- ↑ F.-C. Vogeler: 1.2 Dermatological history and clinical examination . In: The second - compact. Dermatology, ophthalmology, ENT . 1st edition. Springer Medizin Verlag, Heidelberg 2007, ISBN 3-540-46337-2 , p. 7 .
- ^ Karl-Josef Moll: Anatomy: short textbook for the catalog of objects 1 18th edition. Urban & Fischer in Elsevier, 2006, p. 298 u. 299