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endothecium
[en-doh-thee-shee-uhm, -see-uhm]
noun
plural
endotheciathe lining of the cavity of an anther.
(in mosses) the central mass of cells in the rudimentary capsule, from which the archespore is generally developed.
(in bryophytes) the central mass of cells in the capsule, including the spores and columella.
endothecium
/ -sɪəm, ˌɛndəʊˈθiːʃɪəm /
noun
the inner mass of cells of the developing capsule in mosses
the fibrous tissue of the inner wall of an anther
Other Word Forms
- endothecial adjective
- ˌԻˈٳ adjective
Word History and Origins
Origin of endothecium1
Word History and Origins
Origin of endothecium1
Example Sentences
The endothecium varies in thickness, generally becoming thinner towards the part where the anther opens, and there disappears entirely.
Those central cells are the mother-cells of the pollen, whilst the small-celled layer of tissue external to them becomes the endothecium, the exothecium being formed from the epidermal layer.
In Sphagnum, as in Anthoceros, the archesporium is derived from the amphithecium; in all other mosses it is the outermost layer of the endothecium.
The spores are derived from the endothecium, but no distinction of a sterile columella and an archesporium is established in this, a variable number of its cells becoming spore-mother-cells while the rest serve to nourish the spores.
In all other Bryales there is a definite columella extending from the base to the apex of the capsule, the archesporium is derived from the outermost layer of cells of the endothecium, and an air space is formed between the spore-sac and the wall.
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