Tagmosis

Tagmosis

Tagmosis is the evolutionary process of and modifying segments in metameric organisms such as arthropods to form tagmata. In insects, the body segments (somites or metameres) have become fused into three main tagmata: the head, thorax and abdomen. Segments making up each tagma can be either completely fused (e.g. the head capsule) or more loosely connected (e.g. the abdomen).

The Arthropod body plan has undergone various forms of regional specialisation or tagmosis to produce segment groups specialised for different functions. As previously stated these specialised regions are called tagmata. Tagmosis is an extreme form of heteronomy, mediated by Hox genes and the other developmental genes they influence.

Tagmosis varies among the arthropod groups:

Trilobitomorpha- an extinct arthropodic group contains three tagmata- the cephalon (head), thorax and pygidium

Crustacea- also contain three tagmata- the head (cephalon), thorax and abdomen

Hexapoda- also contain three tagmata- the head, thorax and abdomen

Myriapoda- contain 2 tagmata- cephalon and trunk

Cheliformes- contain 2 tagmata- prosoma and opisthosoma


Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • tagmosis — n. [Gr. tagma, an arrangement] The division of a body into groups of segments, forming distinct trunk sections or tagmata …   Dictionary of invertebrate zoology

  • tagmosis — (Subclass Copepoda): The division of the body into functional regions [Boxshall and Halsey, 2004] …   Crustacea glossary

  • tagmosis — tag·mo·sis …   English syllables

  • tagmosis — …   Useful english dictionary

  • prosome — Anterior region of body, commonly limited behind by major articulation. In cirripeds large sac like body in position of head in front of (and rostral from) thoracic limbs, supporting trophi and commonly first cirri [Moore and McCormick, 1969].… …   Crustacea glossary

  • Crustacean — Crustacea Temporal range: 511–0 Ma …   Wikipedia

  • Chelicerata — Temporal range: 445–0 Ma …   Wikipedia

  • Tagma (biology) — In invertebrate biology, a tagma (plural tagmata ) is a specialized grouping of arthropodan segments, such as the head, the thorax, and the abdomen with a common function. The segments of a tagma may be either fused or moveable.Tagma divisions… …   Wikipedia

  • Pattern formation — The science of pattern formation deals with the visible, (statistically) orderly outcomes of self organisation and the common principles behind similar patterns. In developmental biology, pattern formation refers to the generation of complex… …   Wikipedia

  • Hexapoda —   Hexapoda Enallagma cyathiger …   Wikipedia Español

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”