Titlebook: Advances in the Biology of Turbellarians and Related Platyhelminthes; Proceedings of the F Seth Tyler Conference proceedings 1986 Dr W. Jun

尖牙

Frontal organs in the Acoelomorpha (Turbellaria): Ultrastructure and phylogenetic significanceians as being a collection of two to several large mucus-secreting glands whose necks emerge together through a frontal pore at the exact apical pole of the body, i.e. at the point where the pattern of epidermal ciliary rootlets converges. Representatives that we have studied of each of the acoel fa

NAVEN

On the evolution of central nervous systems: Implications from polyclad turbellarian neurobiologyty of cell types including multipolar heteropolar and bipolar neurons. These cell types are rare in other invertebrate ganglia. Individual neurons also contain a variety of different ion channels. both spiking and nonspiking neurons are found. Some neurons are mul-timodal interneurons. Habituation a

Nucleate

Comparative characterization of the nervous system of the Turbellariastem in various representatives of the class. The most primitive state, found in the Acoela, is predominantly plexiform with a varying number of longitudinal trunks. Three, and in some cases four, longitudinal trunks are found in the Proseriata and Temnocephalida. Commissures appear in the Macrostom

exceptional

Neuropeptides in free-living and parasitic flatworms (Platyhelminthes). An immunocytochemical studyhemical method, with the use of antisera to the neuropeptides FMRF- amide, vasotocin, leu-enkephalin, met-enkephalin, neurotensin, somatostatin, and VIP, and to the bioamine serotonin. Anti-FMRF-amide positive perikarya and fibers occurred in all species, while the occurrence of the vertebrate brain

Glucose

DUCE

Embryology of the Turbellaria and its phylogenetic significanceelation to the phylogeny of the Turbellaria. Eggshell granules, which have been demonstrated to occur in the oocytes of entolecithal eggs and the yolk cells of ectolecithal eggs, are compared among species, and their potential value as a taxonomic character is discussed. The quartet 4d spiral cleava

树木心

Experimental evidence for the origins of determinative development in the polyclad turbellariansalians. The polyclads are of particular interest because they provide a link between the regulative development of acoels and the determinative development of annelids and molluscs. Single blastomeres were deleted at the two- and four-cell stages by puncture through the eggshell membrane with tungst

Amendment

Recess

Eggshell formation in polyclads (Turbellaria)as well as secretions of shell glands (SGS), play roles in eggshell formation. As the oocytes pass through the portion of the female tract where the shell glands open, they are surronded by a two-layered envelope of SGS. This envelope prevents the dispersion of SFGs discharged after oviposition, and

obstruct

Fine-structural characteristics of female and male germ cells in Proseriata Otoplanidae (Platyhelminng platyhelminths having ectolecithal eggs..In these species, encompassed in the taxon Proseriata Lithophora, insemination of the germocytes occurs within the germaria. A sperm cell, that has penetrated a germocyte differs in special features from mature male germ cells found in the testes, in parts