prothallus
[ proh-thal-uh s ]
/ proʊˈθæl əs /
noun, plural pro·thal·li [proh-thal-ahy] /proʊˈθæl aɪ/. Botany.
Words nearby prothallus
Example sentences from the Web for prothallus
British Dictionary definitions for prothallus
prothallus
prothallium (prəʊˈθælɪəm)
/ (prəʊˈθæləs) /
noun plural -li (-laɪ) or -lia (-lɪə)
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
Derived forms of prothallus
prothallic or prothallial, adjectiveWord Origin for prothallus
C19: from New Latin, from
pro- before + Greek
thallus a young shoot
Scientific definitions for prothallus
prothallus
[ prō-thăl′əs ]
Plural prothalli (prō-thăl′ī)
The gametophyte of homosporous ferns and some other plants. Prothalli have chlorophyll for photosynthesis, but they are not differentiated into roots, stems, or leaves. They are usually small, flat, and delicate. Prothalli develop from germinated spores, and they bear both archegonia for producing eggs and antheridia for producing sperm. See more at alternation of generations.