(a.) Producing two kinds of spores unlike each other.
Example Sentences:
(1) Axonemes from the heterosporous water fern Marsilea vestita were fixed in the presence of tannic acid and examined by thin-section electron microscopy.
(2) Cytochemical methods are used to examine the distribution and localization of acid phosphatase, non-specific esterase, ribonuclease and peroxidase activity in the walls of the spores of the heterosporous Marsileaceae before and during germination.
(3) The natural ecology of a heterosporous microsporidium, Amblyospora connecticus was investigated at three different salt marsh habitats during 1986-1989.
(4) This situation contrasts with the one described for another heterosporous haploid dioecious pteridophyte, Marsilea vestita, where nucleocytoplasmic interaction has been interpreted as the de novo creation of plastids and mitochondria following the elimination by autophagy of the organelles inherited at meiosis.
(5) This species was found to be heterosporous with two concurrent sporulation sequences in the host larvae, both arising from diplokaryotic meronts and ending with haploid spores.
(6) A new species, Amblyospora trinus, is proposed and its affinities to other heterosporous microsporidia in mosquitoes are discussed.
(7) A microsporidium of the mosquito Aedes aegypti (L.), identified as Nosema aedis Kudo, 1930, was found to be a heterosporous species with 3 sporulation sequences.
Megaspore
Definition:
Example Sentences:
(1) The first, or parasitic classifications of Sabouraud, rests on the morphology of the dermatophytes on the hair in vivo (Achorion, Trichophyton endothrix or ectothrix microides and megaspores, Microsporum) or on the absence of growth on the hair in vivo (Epidermophyton).
(2) The more mature megaspore of Isoetes contains proplastids up to 4 mum in greatest dimension.
(3) The disposition of these organelles in the cell is such that each of the four megaspores delimited during cytokinesis contains a single proplastid.
(4) In Isoetes all 4 megaspores of every tetrad survive and develop, while in Marsilea the mature megasporangium contains a single functional megaspore.
(5) beta-Lectin activity is absent from the megaspore wall.
(6) The resemblance of the plastids in the more mature megaspore to the bodies produced by evagination earlier in development suggests a common identity.
(7) It is possible, however, in the megaspore at least, that the distribution of the activity may to some extent be influenced by a system of exine channels which communicates between the two domains of the wall during sporogenesis.
(8) It is suggested that an explanation to account for the 2 different mechanisms might be sought in regard to the degree of developmental success enjoyed by the individual megaspores in the 2 plants.
(9) The earlier changes observed are in the megaspore which contained many reserve substances (starch; nucleic acids; ascorbic acid; proteins) and enzymes (peroxidase, succinate dehydrogenase, acid phosphatase, alkaline phosphatase and ATP-ase).
(10) The spermatozoid approaches the egg through layers of mucilage that surround the megaspores.