Encyclopedia > Cortex

  Article Content

Cortex

The cortex is the outer portion of the stem[?] or root of a plant, bounded on the outside by the epidermis[?] and on the inside by the pericycle[?]. It is composed mostly of undifferentiated cells[?], usually large thin-walled parenchyma[?] cells. The outer cortical cells often acquire irregularly thickened cell walls, cand are called collenchyma cells. Some of the outer cortical cells may contain chloroplasts.


In zoology, a cortex is the superficial layer of an organ. Organs with well-defined cortical layers include kidneys, adrenal glands, ovaries, the thymus, and portions of the brain. Of these, the brain's cerebral cortex is the most familiar; it is rich in neurons and is the site of most sophisticated neural processing.

There is no common origin or structure between the various cortexes, their only commonality is that they are distinctive layers at the surfaces of the organs involved.



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Olympic medalists in athletics (men)

... Paavo Yrjölä (FIN) 1932 Jim Bausch (USA) 1936 Glenn Morris (USA) 1948 Bob Mathias (USA) 1952 Bob Mathias (USA) 1956 Milt Campbell (USA) 1960 Rafer Johnson ...