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A lymph heart is an organ which pumps lymph in lungfishes, amphibians, reptiles, and flightless birds back into the circulatory system. [ 1 ] [ 2 ] In some amphibian species, lymph hearts are in pairs, and may number as many as 200 in one animal the size of a worm , while newts and salamanders have as many as 16 to 23 pairs of lymph hearts.
At this location, neuroscientist Otto Loewi first demonstrated that nerves secrete substances called neurotransmitters, which have effects on receptors in target tissues. In his experiment, Loewi electrically stimulated the vagus nerve of a frog heart, which slowed the heart.
In 1852 H.F. Stannius experimented on the heart. By tying a ligature as a constriction between the sinus venosus and the atrium in the frog and also one around the atrioventricular groove, Stannius was able to demonstrate that the muscle tissues of the atria and ventricles have independent and spontaneous rhythms.
The general background coloration of most glass frogs is primarily lime green, the abdominal skin of some members of this family is transparent and translucent, giving the glass frog its common name. The internal viscera, including the heart, liver, and gastrointestinal tract, are visible through the skin. When active their blood makes them ...
Frogs and toads are broadly classified into three suborders: Archaeobatrachia, which includes four families of primitive frogs; Mesobatrachia, which includes five families of more evolutionary intermediate frogs; and Neobatrachia, by far the largest group, which contains the remaining families of modern frogs, including most common species ...
The Goliath frog, however, was mainly infected by Nematodes (90.5%) which is a specific type of roundworm. The helminth species discovered within the Goliath frog was extremely similar to those discovered in amphibian hosts in other African countries emphasizing that its location/habitat is the main cause of the prevalence of this predator.
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The early bulbus cordis is formed by the fifth week of development. [4] The truncus arteriosus is derived from it later. [2]The adjacent walls of the bulbus cordis and ventricle approximate, fuse, and finally disappear, and the bulbus cordis now communicates freely with the right ventricle, while the junction of the bulbus with the truncus arteriosus is brought directly ventral to and applied ...