(n. pl.) Those animals in which the protoplasmic mass, constituting the egg, is converted into a multitude of cells, which are metamorphosed into the tissues of the body. A central cavity is commonly developed, and the cells around it are at first arranged in two layers, -- the ectoderm and endoderm. The group comprises nearly all animals except the Protozoa.
Example Sentences:
(1) Phyla as diverse as insects, birds, and mammals possess distinct HRAS and KRAS sequences, suggesting that these genes are essential to metazoa.
(2) The unique structure of these cilia has systematic and phylogenetic significance for the Acoela, and it is argued that ultrastructural characters in general, including characters of organelles, can be validly applied to the phylogeny and systematics of the Metazoa.
(3) In Metazoa single receptory flagellar cells are differentiated; they realize conservatively some receptive molecules that are already prepared by their ancessors--Eukaryota.
(4) Together with previous results that showed the existence of a nonfibrillar collagen in the same species, these data demonstrate that at least two collagen gene families are represented in the most primitive metazoa.
(5) The origin of metazoa implies the passage from an eukarote protozoan to a protozygote ancestor of a metazoan zygote.
(6) RNA synthesis and processing in A. nidulans mitochondria therefore resembles the events occurring in metazoa rather than yeast.
(7) Comparison of the sequences obtained from the different species indicate that the metazoan lineages all appear to have arisen at approximately the same time and significantly later than the time of divergence of yeast from the common ancestor of the Metazoa.
(8) This is the first report in a nutritional role of peptides in invertebrate metazoa.
(9) In these phylogenies the Ciliophora diverged from the eukaryotic line of descent as a loose phylogenetic grouping during a radiative period that gave rise to the Fungi, the Plantae and the Metazoa.
(10) Analysis of messenger RNA splicing in yeast and in metazoa has led to the identification of an RNA molecule in a lariat conformation.
(11) These findings support the view that Myxosporidia are Metazoa and raise the problem of their origin.
(12) A variety of microorganisms and metazoa was observed, including a baculovirus, gram-negative bacteria, rickettsia-like organisms, amoebae, trypanosomatid flagellates, cephaline gregarines, and microsporidia.
(13) Organisms with defective or with no lymphocytic function are able to live for a certain time while metazoa cannot develop and exist without cells capable of phagocytosis.
(14) Polyploidy--the doubling of chromosome sets of cells caused by a stop of mitosis at different levels of the mitotic cycle--is a phenomenon widely observed in plants, protozoa, metazoa, and animals.
(15) In Metazoa two types of locomotion take place according to the function of regulatory genes: initial flagellar and muscular definitive apparatus.
(16) The presence of spasmins in other Protozoa and in some Metazoa was also investigated.
(17) At this stage, the swimming Metazoa of the thermocline could adapt to a benthic environment on the shelves by developing exoskeletons.
(18) These analyses indicate that (i) the Metazoa is a monophyletic taxon; (ii) the Deuterostomia is a monophyletic taxon; (iii) the Annelida-Mollusca lineage is the sister group of an arthropod subgroup; and (iv) the last common ancestor of the Annelida-Mollusca lineage is most parsimoniously derived from a segmented, hemocoelic ancestor with an open circulatory system.
(19) Tubulin and dinein with ATPh-ase activity are included in the flagella composition of LSS in Eukaryota, actin and miozin--with a high ATPh-ase activity--in composition of LSS myofilaments in ameboid Eukaryota and locomotor musculature in Metazoa.
(20) Comparative evidence on the lack of three important organelles (flagella, Golgi-complex, mitochondria) in cells and organisms at the cellular level of organization has been summarized for all the four eukaryotic kingdoms--Protista, Fungi, Plantae and Animalia (Metazoa).
Protozoa
Definition:
(n. pl.) The lowest of the grand divisions of the animal kingdom.
(pl. ) of Protozoon
Example Sentences:
(1) Many protozoa were in renal tubule cells, endothelial cells and brain.
(2) The 8-, 9-, 10-, and 11-thiastearic acids were found to suppress the synthesis of the cyclopropane-containing fatty acid dihydrosterculic acid (9,10-methyleneoctadecanoic acid) at micromolar concentrations in the growth medium, and all but the 9-thiastearate were found to inhibit the growth of the protozoa at concentrations.
(3) On defaunation of the rumen to remove ciliated protozoa the concentration of phosphatidylcholine in ruminal digesta falls markedly and becomes lower than that in abomasal digesta.
(4) Protozoa were found in 32% of samples (4.6% pathogenic protozoa, 24% facultative pathogenic protozoa and 3.4% apathogenic protozoa).
(5) Omasal contents were collected from slaughtered cattle (n = 54), bison (n = 15), and sheep (n = 40) to determine numbers and generic distribution of ciliated protozoa.
(6) In an attempt to reconstruct the universal ancestor of all present-day tubulin genes the intron positions in 38 different alpha- and beta-tubulin genes from plants, animals, fungi and protozoa were compared.
(7) The drug possesses a strong activity against numerous fungi, some protozoa, and bacteria.
(8) Low GC in Mycoplasma is accompanied by use of UGA for tryptophan and, in ciliated protozoa, by use of UAA and UAG for glutamine.
(9) In addition, a number of antiparasitic agents have been shown to exert their actions through a free radical metabolism: nitro compounds used against trypanosomatids, anaerobic protozoa and helminths; crystal violet used in blood banks to prevent blood transmission of Chagas' disease; the antimalarial primaquine, chloroquinine, and quinhasou; and quinones active in vitro and in vivo against different parasites.
(10) Optimal doses of promastigotes were used which ensured the adaptation of Protozoa in the host's intestine.
(11) In this case the fraction responsible for this transformation contains mainly protozoa.
(12) The apparent production rate of the larger protozoa indicates that they contribute only about 9% of the predicted net microbial protein synthesis in the rumen.
(13) The observation, in parasitic protozoa and helminths, that selfing or non-obligatory mating is a common feature suggests that these processes may be strategies to overcome the cost of meiosis.
(14) Nitroimidazoles have been prepared which show interesting activity against the bacterium, Neisseria gonorrhoeae, in addition to the activities usually shown by nitroimidazoles against protozoa and anaerobic bacteria.
(15) Antigenic macromolecules and some viruses, bacteria, and protozoa enter their apical surface by endocytosis or phagocytosis.
(16) Trapping of many types of small protozoa and manipulation of organelles within protozoa is also possible.
(17) These associations are also compared with other, previously described cases of symbiosis involving prokaryotes and protozoa.
(18) Although C. ventriculi is classified as a holotrich, concentrations of this species in the rumen appear to follow a diurnal cycle more closely related to be entodiniomorph protozoa.
(19) In a later phase, the protozoa treated with histamine or prednisolone died.
(20) The stool samples were examined for the presence of Cryptosporidium sp., other protozoa, helminths, and pathogenic enterobacteria.