(n.) The male reproductive apparatus in the lower, consisting of a cell or other cavity in which spermatozoids are produced; -- called also spermary.
Example Sentences:
(1) During the development of an antheridium DNA content in manubria gradually increases to 8C-16C level.
(2) This critical moment of spermatogenesis is probably induced by the regulators operating at the level of an antheridium.
(3) In the cytoplasm of the manubria there are numerous secretive vesicles filled with fine-granular substance discharged outside plasmalemma, active Golgi apparatus, well-developed rough ER, numerous polysomes, mitochondria with the condensed structure and plastids with granar and inter-granar thylakoids as well as plastoglobules which increase in number and size along with the development of the antheridium.
(4) It has been assumed that changes in structural organization as well as growth character of shield cells constitute the factor regulating the exchange with external environment, determine light spectrum penetrating to the antheridium and the volume of antheridial space.
(5) The internal space of the antheridium in Chara vulgaris L. is filled with the PAS-positive mucilage which is of pectic nature.
Oogonium
Definition:
(n.) A special cell in certain cryptogamous plants containing oospheres, as in the rockweeds (Fucus), and the orders Vaucherieae and Peronosporeae.
Example Sentences:
(1) This immunocytochemical evidence supports the hypothesis that the DNA of the inactive X-chromosome of the human 17-week gestation oogonium is methylated.
(2) In situ nucleic acid hybridization showed that the synthesis of nucleolar DNA begins in oogonium and proceeds slowly through leptotene and zygotene when a small amount of extrachromosomal nucleolar DNA is produced.
(3) These vesicles (V1) are formed originally in unfertilized eggs by smooth endoplasmic reticulum (SER) after release of the eggs from the oogonium.
(4) In connection with this, it is suggested that the term "oogonium" (which is used to designate such cells in the literature) be retained only for proliferating i-cells containing finely filamentous nuclear material in the cytoplasm in the genital zone of the hydra.
(5) In this way, in vitro development from oogonium to larva has been maintained for several generations.
(6) P. diclinum (synonymous with P. gracile sensu Middleton) showed minor differences in vesicle, oospore and oogonium size from P. destruens.
(7) Prior to meiosis in triploid gynogenetic all-female forms of Poeciliopsis, the chromosome number of the nucleus of the triploid oogonium is raised endomitotically to hexaploid.