Search results
Results From The WOW.Com Content Network
The cardiac skeleton binds several bands of dense connective tissue, as collagen, that encircle the bases of the pulmonary trunk, aorta, and all four heart valves. [2] While not a traditionally or "true" or rigid skeleton , it does provide structure and support for the heart, as well as isolate the atria from the ventricles.
Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem Detail of the vasculature of a bramble leaf Translocation in vascular plants. Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem ...
Cardiac physiology or heart function is the study of healthy, unimpaired function of the heart: involving blood flow; myocardium structure; the electrical conduction system of the heart; the cardiac cycle and cardiac output and how these interact and depend on one another.
In plants, organogenesis occurs continuously and only stops when the plant dies. In the shoot, the shoot apical meristems regularly produce new lateral organs (leaves or flowers) and lateral branches. In the root, new lateral roots form from weakly differentiated internal tissue (e.g. the xylem-pole pericycle in the model plant Arabidopsis ...
The trabeculae carneae (columnae carneae or meaty ridges) are rounded or irregular muscular columns which project from the inner surface of the right and left ventricle of the heart. [1] These are different from the pectinate muscles, which are present in the atria of the heart. In development, trabeculae carneae are among the first of the ...
A germination rate experiment. Plant physiology is a subdiscipline of botany concerned with the functioning, or physiology, of plants. [1]Plant physiologists study fundamental processes of plants, such as photosynthesis, respiration, plant nutrition, plant hormone functions, tropisms, nastic movements, photoperiodism, photomorphogenesis, circadian rhythms, environmental stress physiology, seed ...
Ryanodine receptors mediate the release of calcium ions from the sarcoplasmic reticulum and endoplasmic reticulum, an essential step in muscle contraction. [1] In skeletal muscle, activation of ryanodine receptors occurs via a physical coupling to the dihydropyridine receptor (a voltage-dependent, L-type calcium channel), whereas, in cardiac muscle, the primary mechanism of activation is ...
The coronary sinus runs transversely in the left atrioventricular groove (coronary sulcus) on the posterior aspect of the heart. [5] The sinus, before entering the right atrium, is considerably dilated - nearly to the size of the end of the little finger.