Is the flow in the giraffe's jugular vein a 'free' fall?

Autor:	Henry S. Badeer
Rok vydání:	1997
Předmět:	business.industry Models Cardiovascular Blood Pressure General Medicine Blood flow Anatomy Regional Blood Flow Jugular vein cardiovascular system Animals Medicine Vascular Resistance Pressure work Jugular Veins Neck veins business Artiodactyla Gravitation
Zdroj:	Comparative Biochemistry and Physiology Part A: Physiology. 118:573-576
ISSN:	0300-9629
DOI:	10.1016/s0300-9629(96)00376-3
Popis:	There is controversy as to whether or not the heart works against gravity in the arteries to the head in the upright position. One view is that the gravitational effects in the neck arteries are counterbalanced by the gravitational effects in the veins of the neck and the heart does not do extra pressure work. This concept has been challenged by others who claim that the heart works against gravity based on the notion that the jugular vein is collapsed and gravitational effects on jugular blood are inoperative, similar to the "free" fall of liquids. The present study supports the view that blood flow in the collapsible jugular vein of the giraffe is not a "free" fall and that the heart does not spend extra energy to raise the blood to the head.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::614beb0900a862df619a99a3115aecc3 https://doi.org/10.1016/s0300-9629(96)00376-3 Zobrazit plný text záznamu