Search results
Results from the WOW.Com Content Network
The endocardial endothelium may also act as a kind of blood–heart barrier (analogous to the blood–brain barrier), thus controlling the ionic composition of the extracellular fluid in which the cardiomyocytes bathe.
The endocardial cushions are thought to arise from a subset of endothelial cells that undergo epithelial-mesenchymal transition, a process whereby these cells break cell-to-cell contacts and migrate into the cardiac jelly (towards the interior of the heart tube). These migrated cells form the "swellings" called the endocardial cushions seen in ...
The endocardial tubes have an intimate proximity to the foregut or pharyngeal endoderm. [ 1 ] As folding of the embryo in the horizontal plane initiates in the 4th week of gestation, the endocardial tubes meet in the midline to form the primitive heart tube , which will eventually develop into the histologically definitive endocardium .
Also in 2016, Quizlet launched "Quizlet Live", a real-time online matching game where teams compete to answer all 12 questions correctly without an incorrect answer along the way. [15] In 2017, Quizlet created a premium offering called "Quizlet Go" (later renamed "Quizlet Plus"), with additional features available for paid subscribers.
This begins with the formation of two endocardial tubes which merge to form the tubular heart, also called the primitive heart tube. The heart is the first functional organ in vertebrate embryos . The tubular heart quickly differentiates into the truncus arteriosus , bulbus cordis , primitive ventricle , primitive atrium , and the sinus venosus .
The Leitner system for scheduling flashcards was introduced by German scientific journalist Sebastian Leitner in the 1970s with his book, So lernt man lernen. [6] Later, the SuperMemo program and algorithm (specifically the SM-2 algorithm, which is the most popular in other programs) was introduced in 1987 by Polish researcher Piotr Woźniak .
The unpaired umbilical vein carries oxygen and nutrient rich blood derived from fetal-maternal blood exchange at the chorionic villi.More than two-thirds of fetal hepatic circulation is via the main portal vein, while the remainder is shunted from the left portal vein via the ductus venosus to the inferior vena cava, eventually being delivered to the fetal right atrium.
A biological system is a complex network which connects several biologically relevant entities. Biological organization spans several scales and are determined based different structures depending on what the system is. [1]