(n.) A genus of Monotremata found in Australia, Tasmania, and New Guinea. They are toothless and covered with spines; -- called also porcupine ant-eater, and Australian ant-eater.
Example Sentences:
(1) In the echidna a few dark, organelle-rich glia cells were encountered.
(2) This study provides anatomical evidence for the presence of cone-like photoreceptors in the retina of the echidna.
(3) This is a report of experiments which provide evidence in support of the existence of an electric sense in the echidna, or spiny anteater Tachyglossus aculeatus.
(4) Echidna Mb, which has one replacement (Glu-59 to Ala) within region 56-62, displayed greatly reduced cross-reactivities and relative binding affinities.
(5) Echidna band A protein has some similarity to high cystine "whey" proteins.
(6) The concentration of pituitary LH is in the range of that found in eutherian mammals, but the concentration of ACTH is lower than that reported for other vertebrates, and this may be linked causally with the remarkably low rate of corticosteroid secretion in the echidna.
(7) The presence of two lysozyme variants, echidna lysozyme I and II, has been confirmed in mature milk samples of Tachyglossus aculeatus multiaculeatus and Tachyglossus aculeatus aculeatus respectively.
(8) There is a wide disparity in growth rates of echidna young that is related to differences in the body weights of the mothers.
(9) At the time of publishing the list stands at 244, including, but certainly not limited to: disturbed balance; blurred vision; cataracts; mass bee extinction; unexplained deaths of cattle, goats, dolphins, worms and sundry other animals; family discord; disoriented echidnas; social problems among peacocks; and eggs without yolks.
(10) The gross anatomy and nerve supply of the bill of echidna (Tachyglossus aculeatus) is described in relation to its function as an outstanding sensory organ.
(11) Within the rostral one centimetre of the Echidna beak, three specialised receptors were found: a mucous sensory gland, a rod-like structure, and an innervated epidermal pit.
(12) The cells of the secretory tubules in the mandibular gland of the echidna are packed with fairly large birefringent granules, which show a lamellated structure consisting of alternating thin and thick layers or shells of protein.
(13) Adult Aponomma concolor were able to locate their mammalian host (echidna) from distances greater than 3 reptile-infesting species could locate their hosts.
(14) Generally there are more changes between beta-chains; there are only three other examples reported where there are more changes between alpha-chains than beta-chains, these are of echidna, rabbit and dog globins.
(15) Maturation of spermatozoa in the Wolffian duct of the echidna appears to be expressed only in a changing capacity for motility and in loss of the cytoplasmic droplet.
(16) The karyotype of the platypus (2n = 52) has several features in common with those of the echidna species; six pairs of large autosomes, many pairs of small (but not micro-) chromosomes, and a series of small unpaired chromosomes which form a multivalent at meiosis.
(17) Neurohypophysial hormones of platypus seem similar to those of echidna, the other living prototherian, and to those of most placental mammals.
(18) The same properties make this formation different from the anterodorsal and anteroventral nuclei in rats, the equivalents of which could not be identified in echidnas.
(19) An additional nine live echidnas were presented for clinical examination for dog or fox wounds (eight), or wire snare wounds (one).
(20) Statistical comparison of amino acid composition of the component chains with other immunoglobulin heavy chains suggests that echidna gamma chains are more closely related to eutherian gamma chains than to the 7S Ig heavy chains from amphibia or aves.
Monotreme
Definition:
(n.) One of the Monotremata.
Example Sentences:
(1) By contrast, the growth of the oocyte in relation to the follicle in monotremes in linear throughout the whole period of follicular growth.
(2) The mammals examined included 3 eutherian, 2 marsupial and a monotreme species and the reptiles 2 saurian, 1 crocodilian and 1 testudine species.
(3) Monotreme enamel has been interpreted as representing a structural stage intermediate between that of known multituberculates and extant tribosphenid mammals.
(4) No sex difference was observed in any monotreme tissue.
(5) The possible role these and the native rodents, marsupials and monotremes would play should an exotic disease of livestock enter Australia is discussed.
(6) A dorsal pterygoid element and a ventral ectopterygoid element can be recognised during the development of monotremes, marsupials and eutherian mammals.
(7) The ratio of the contents of the two major mammalian ganglioside fractions GD1a and GT1b is generally in the range of 1.0 and even higher; in the heterothermic platypus from the monotremes and in hibernators among the placental mammals, however, it is much lower (about 0.8).
(8) Because monotremes and marsupials diverged independently from eutherian mammals, this finding implies that the whole human X short arm region is a relatively recent addition to the X chromosome in eutherian mammals.
(9) Several lines of evidence suggest that electroreception has evolved independently in this monotreme.
(10) Since marsupials and monotremes diverged independently from eutherians, these data suggest that HSA 21 genes were originally located in two separate autosomal blocks.
(11) Here we establish that the platypus, the Australian nocturnal diving monotreme, can locate and avoid objects on the basis of d.c. fields.
(12) In monotremes the elements remain distinct and show specialised features, including a hamular cartilage in the ectopterygoid of one specimen of Ornithorhynchus.
(13) In order to extend comparative mapping studies to the monotreme mammals (subclass Prototheria), somatic-cell hybrids were obtained between Chinese-hamster cells deficient in hypoxanthine phosphoribosyltransferase (HPRT) and platypus fibroblasts.
(14) The amino acid sequence showed approximately 85 differences from mammalian, monotreme and bird myoglobins.
(15) There was no ligament of the femoral head in the hip joints of the monotremes, and it is suggested the absence of a ligament may be significant in the development of the cavity.
(16) The present study examines the cartilaginous epiphyses and physes from the knee and hip of the rat and the two Australian monotremes (platypus, Ornithorhynchus anatinus and echidna, Tachyglossus aculeatus).
(17) A region represented by the short arm of the human X is common to the X in all eutherians, but is autosomal in marsupials and monotremes; thus it was not a part of the original X, and must have been acquired by the X early in the eutherian radiation.
(18) The enamel of the fossil monotreme is prismatic and tubular and displays large areas of Pattern 2 prism packing.
(19) This estimate agrees well with similar estimates made using alpha- and beta-globin sequences, in contrast to widely differing estimates of dates of divergence for monotremes using the same three globin chains.
(20) Xenoantisera directed against human heavy chain isotypes allowed the serological identification of IgM and IgG immunoglobulins in the echidna (Tachyglossus aculeatus), a monotreme which is one of the most primitive species of extant mammals.