prothallium

prothallium

[proh-thal-ee-uhm]
noun, plural prothallia [proh-thal-ee-uh] .
1.
Botany. the gametophyte of ferns and related plants.
2.
the analogous rudimentary gametophyte of seed-bearing plants.

Origin:
1855–60; < Neo-Latin < Greek pro- pro-2 + thallíon, diminutive of thallós young shoot; see -ium

prothallial, prothallic, prothalline [proh-thal-een, -ahyn] , adjective
prothalloid, adjective
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To prothallium
Collins
World English Dictionary
prothallus or prothallium (prəʊˈθæləs, prəʊˈθælɪəm)
 
n , pl -li, -lia
botany the small flat free-living gametophyte that bears the reproductive organs of ferns, horsetails, and club mosses. It is either a green disc on the soil surface or it is colourless and subterranean
 
[C19: from New Latin, from pro- before + Greek thallus a young shoot]
 
prothallium or prothallium (prəʊˈθæləs, prəʊˈθælɪəm, -laɪ, -lɪə)
 
n
 
[C19: from New Latin, from pro- before + Greek thallus a young shoot]
 
pro'thallic or prothallium
 
adj
 
pro'thallial or prothallium
 
adj

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Encyclopedia Britannica
Encyclopedia

prothallium

the small, green, heart-shaped structure (gametophyte) of a fern that produces both male and female sex cells (gametes). The prothallium forms from a spore. After fertilization, a young sporophyte plant develops; it consists of a primary root, primary leaf, the rudiment of a new stem, and an organ, called a foot, that absorbs food from the gametophyte.

Learn more about prothallium with a free trial on Britannica.com.

Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
Cite This Source
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature
FAVORITES
RECENT

;