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In humans, the vermiform appendix is sometimes called a vestigial structure as it has lost much of its ancestral digestive function. Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. [1]
Appendix testis, a vestigial remnant of the Müllerian duct; Epiploic appendix, one of several small pouches of fat on the peritoneum along the colon and rectum Appendix of the laryngeal ventricle, a sac that extends from the laryngeal ventricle; Mesoappendix, the portion of the mesentery that connects the ileum to the vermiform appendix
Ileum, caecum and colon of rabbit, showing Appendix vermiformis on fully functional caecum The human vermiform appendix on the vestigial caecum. The appendix was once believed to be a vestige of a redundant organ that in ancestral species had digestive functions, much as it still does in extant species in which intestinal flora hydrolyze cellulose and similar indigestible plant materials. [10]
Plant anatomy or phytotomy is the general term for the study of the internal structure of plants.Originally, it included plant morphology, the description of the physical form and external structure of plants, but since the mid-20th century, plant anatomy has been considered a separate field referring only to internal plant structure.
Plant structures or organs fulfil specific functions, and those functions determine the structures that perform them. Among terrestrial (land) plants, the vascular and non-vascular plants (Bryophytes) evolved independently in terms of their adaptation to terrestrial life and are treated separately here (see Bryophytes). [6]
Stipules have various functions. Some stipules are not well understood or may be vestigial. It is known that foliaceous stipules are used like leaves to make energy for the plants. Sometimes stipules protect the next leaf or bud as it grows in then falls off after the leaf unfolds, as with Tulip Poplars. [4]
While the Vermes is no longer a taxonomic group, anatomists continue to use the description "vermiform" of animals or organs that are worm-shaped. The word root is Latin, vermes (worms) and formes (shaped). [3] A well known example is the vermiform appendix, a small, blind section of the gut in humans and a number of other mammals. [4]
The standard nucleomorph is the result of secondary endosymbiosis: a cyanobacterium first became the chloroplast of ancestral plants, which diverged into green and red algae among other groups; the algal cell is then captured by another eukaryote.