|
Search over 100 encyclopedias and dictionaries: |
Research categories | Follow us on Twitter |
Research categories
View all topics in the newsView all reference sources at Encyclopedia.com |
|||
theca
theca (pl. thecae)
1. Shell or test. 2. The cell wall in some protistan algae, e.g. diatoms and dinoflagellates (see DINOPHYCEAE). 3. The dense wall at the margin of a corallite in a scleractinian coral (Scleractinia). 4. In graptolites (Graptolithina), one of the cup-like structures that occur along the stipe, each of which houses an individual member of the colony. Thecae vary from simple, straight-sided tubular structures to those with an introtorted opening, where the thecal aperture faces downward. There are triangulate thecae with very small apertures and in some species the thecae are long, thin, and separated from one another (‘isolate’). In some monograptids the thecae vary in structure along the length of an individual stipe as well as from one species to another. Thecal shape also varies through time. |
|
|
Cite this article
AILSA ALLABY and MICHAEL ALLABY. "theca." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "theca." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O13-theca.html AILSA ALLABY and MICHAEL ALLABY. "theca." A Dictionary of Earth Sciences. 1999. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-theca.html |
|
theca
theca The case inside which an individual member of a colony of invertebrates lives. See AUTOTHECA; BITHECA; STOLOTHECA.
|
|
|
Cite this article
MICHAEL ALLABY. "theca." A Dictionary of Zoology. 1999. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "theca." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O8-theca.html MICHAEL ALLABY. "theca." A Dictionary of Zoology. 1999. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-theca.html |
|
theca
theca receptacle, cell, case. XVII. — L. thēca — Gr. thḗkē case, cover.
|
|
|
Cite this article
T. F. HOAD. "theca." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "theca." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O27-theca.html T. F. HOAD. "theca." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-theca.html |
|
theca
theca The shell-like structure surrounding the cell in certain algae.
|
|
|
Cite this article
MICHAEL ALLABY. "theca." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "theca." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O7-theca.html MICHAEL ALLABY. "theca." A Dictionary of Plant Sciences. 1998. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-theca.html |
|
theca
theca (th'ee-kă) n. a sheathlike surrounding tissue.
|
|
|
Cite this article
"theca." A Dictionary of Nursing. 2008. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. "theca." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O62-theca.html "theca." A Dictionary of Nursing. 2008. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-theca.html |
|
theca
theca See capsule.
|
|
|
Cite this article
"theca." A Dictionary of Biology. 2004. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. "theca." A Dictionary of Biology. 2004. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O6-theca.html "theca." A Dictionary of Biology. 2004. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-theca.html |
|
theca
theca
•acre, baker, breaker, Chandrasekhar, faker, forsaker, Jamaica, Laker, maker, nacre, partaker, Quaker, raker, saker, shaker, staker, taker, undertaker, waker
•bellyacher • matchmaker • bedmaker
•dressmaker
•haymaker, playmaker
•sailmaker • rainmaker
•lacemaker, pacemaker
•peacemaker • filmmaker • kingmaker
•printmaker • holidaymaker
•cabinetmaker • moneymaker
•merrymaker • watchmaker
•clockmaker • lawmaker • homemaker
•bookmaker • troublemaker
•boilermaker • heartbreaker
•safebreaker • Windbreaker
•tie-breaker • strikebreaker
•icebreaker • jawbreaker
•housebreaker • muckraker
•boneshaker • caretaker • piss-taker
•stavesacre • wiseacre
•beaker, Costa Rica, Dominica, eureka, Frederica, Griqua, leaker, loudspeaker, seeker, shrieker, sika, sneaker, speaker, squeaker, streaker, Tanganyika, theca, tikka, Topeka, wreaker
|
|
|
Cite this article
"theca." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>. "theca." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O233-theca.html "theca." Oxford Dictionary of Rhymes. 2007. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-theca.html |
|
Search over 100 encyclopedias and dictionaries:
HighBeam™ Research, Inc. © Copyright 2012. All rights reserved.
The Encyclopedia.com advertising network includes:
