Search results
Results from the WOW.Com Content Network
By the time Loewi began his experiments there was much discussion among scientists whether communication between nerves and muscles was chemical or electrical by nature. . Experiments by Luigi Galvani in the 18th century had demonstrated that electrical stimulation of the frog sciatic nerve resulted in twitching of the leg muscles, and from this he developed the concept of bioelectri
Loewi's famous experiment, published in 1921, largely answered this question. He dissected out of frogs two beating hearts: one with the vagus nerve which controls heart rate attached, the other heart on its own. Both hearts were bathed in a saline solution (i.e. Ringer's solution).
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.
Through experiments on the heart of snails and with a series of 19 observations on frog's heart, he was able to demonstrate the direct relationship between the volume of blood contained in the heart cavities and the contractile energy of the heart and consequently how, within certain limits, the lengthening of the heart fibers, cause of the ...
When hyperstimulated, the left vagal branch predisposes the heart to conduction block at the atrioventricular node. 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 ...
Jennifer Lopez is looking back on 2024 with gratitude, and toward 2025 with positivity.. The actress and singer posted a video montage recapping her year with some memorable moments featured ...
In an experiment, Fowler's toad (Bufo ... H. F. Stannius used a frog's heart in a procedure called a Stannius ligature to demonstrate the ventricle and atria beat ...
Sen. Josh Hawley (R-Mo.) is asking the Senate Homeland Security Committee to call on Homeland Security Secretary Alejandro Mayorkas and FBI director Christopher Wray to testify after the New ...