Bulbous corydalis (Corydalis cava) or bird in the bush, is a highly poisonous perennialherb of the family Fumariaceae, with a large, hollow, globose underground tuber with wiry roots. The stem is erect and bears two biternate lobed leaves, bluish-green below and light green above. The flowers are irregularly shaped, violet or white in colour, and arranged in a solitary terminal raceme. The upper petal is drawn out into a long apically curved spur. Bulbous corydalis is found throughout Europe and neighbouring Asia growing in open woods and hedgerows. Research Bulbous Corydalis
The left atrium is a small upper cavity of the heart. Oxygen rich blood returns from the lungs through the four pulmonary veins into the smooth chamber of the left atrium. The chamber is constructed of two overlapping layers of muscle: a superficial layer and an inner layer, composed of many small bundles. The wall of the chamber is slightly thicker and more powerful than the right atrium. As the heart contracts (ventricular systole), blood flows into the ascending aorta through the aortic arch. As the heart relaxes (ventriclediastole), the blood flows through the mitral valve to the left ventricle. The right atrium is a small upper cavity of the heart that holds about three-and-a-half tablespoons of blood. It serves as the receiving chamber for all the venous blood (short of oxygen and laden with carbon dioxide) returning through the superior and inferior vena cava, and from many minute blood vessels that drainblood from the walls of the chamber itself. The right atrium is slightly larger than the left atrium, which is slightly more powerful. The walls of the right atrium are less than an eighth of an inch thick. Two layers of muscle form the wall. The superficial layer spans both atria, and the inner layer, composed of many small bundles, arches over the atrial cavity at right angles to the superficial layer. As the heart contracts (ventricular systole), the blood is pushed through the pulmonary valve into pulmonary circulation. As the heart relaxes (ventricular diastole), the blood exits the right atrium through the tricuspid valve to the right ventricle. In the upper part of the right atrium there is a small patch of special hearttissue called the sinus node or the sinoatrial node. It is the heartspacemaker, triggering the heartbeat and establishes its rate. Research Atrium
The coronary vein is often referred to as the great cardiac vein of the heart. It is a large vein with two branches, the left coronary vein and the right coronary vein. The vein commences at the apex of the heart and ascends along the heart to the base of the ventricles. It then curves left to the back part of the heart and opens into the left coronary sinus, which is about 2.5 centimeters in length and terminates in the right atrium near the inferior vena cava. Research Coronary Vein
The eustachian valve is one of the valves of the heart, lying at the point where the inferior vena cava empties itself into the right auricle. Research Eustachian Valve
There are two gastroepiploic veins. One is a small vein, that corresponds to the hepatic artery. The other is a large vein, that corresponds to the gastric artery. Both veins receive blood from the stomach and converge with the vena cava. Research Gastroepiploic Vein
The heart is a hollow pear-shaped muscular organ placed between the lungs in the middle of the chest that pumps blood through the body, supplying cells with oxygen and nutrients.
The heart in humans, quadrupeds, birds, and some reptiles is composed of four cavities, two auricles and two ventricles. It is enveloped in a membrane called the pericardium, and is situated toward the left of the cavity of the chest, between the lungs. With each beat the apex of the heart strikes against the wall of the chest in the space between the 5th and 6th ribs, a little below and to the right of the left nipple. The right auricle communicates with the right ventricle, besides which there are in it three openings, that of the vena cava inferior, that of the vena cava superior, and that of the coronary vein. The communication between this auricle and ventricle is closed by a valve when the ventricle contracts. The right ventricle communicates with the pulmonary artery, the opening into the artery being guarded by a valve formed of three flaps. When these are brought together they interrupt the communication between the ventricle and the artery. The left auricle communicates through a valved opening with the left ventricle, and contains the orifices of the four pulmonary veins. The left ventricle, besides the communication with the left auricle, contains the orifice of the aorta, also provided with a valve similar to that of the pulmonary artery.
The auricles and ventricle of one side are separated from those of the other by a complete muscular partition, the septum cordis. The valves at the openings of the arteries are called semilunar, that at the orifice of the right auricle tricuspid, that at the orifice of the left auricle mitral, and that at the orifice of the vena cava inferior the Eustachian valve.
The heart is formed of a firm thick muscular tissue, composed of fibres interlacing so as to form a figure of eight. It also contains nerves and vessels.
The arteries carry the blood from the heart to all parts of the body. They terminate in the capillary vessels, a series of extremely minute tubes which pass over into the veins.
The veins are the channels by which the blood passes back from the body to the right auricle of the heart. The blood which is returned from the veins is purplish red, from the presence of carbon dioxide and deficiency in oxygen, and is called venous; that which leaves the heart is bright red, being oxygenated, and is called arterial.
The venous blood parts with its carbon dioxide and receives new supplies of oxygen in the capillary system of the lungs, flows into the pulmonary veins, thence into the left cavities of the heart, thence it passes into the aorta, and is transmitted to all parts of the body, returning to the veins by the capillary system. It has now become venous, passes through the veins from the extremities towards the heart, receiving the chyle and the lymph, and is emptied into the right cavities of that organ, which returns it through the pulmonary artery to the capillary vessels of the lungs, where it is subjected to the influence of the air, resumes the qualities of red or arterial blood, and is ready for a new course.
The mechanism of the circulation is as follows: The blood contained in the two venae cavae is poured into the right auricle, which contracts, and thus forces the fluid to escape; but the venae cavae oppose to its backward passage the column of blood which they contain, and it must therefore pass into the right ventricle. The ventricle then contracts, and the tricuspid valve closing the passage through which the liquid entered, it is forced into the pulmonary artery, along which it must flow (return to the ventricle being prevented by the semi-lunar valve) into the capillary system of the lungs, whence it passes into the pulmonary veins, which pour it into the left auricle by four orifices.
The contraction of the auricle impels it into the left ventricle, by which it is driven forward into the aorta (the mitral valve preventing its return into the auricle), and thence into the general circulation. The two auricles contract and relax simultaneously with each other, as do also the two ventricles. The relaxation is called diastole; the contraction systole.
The quantity of blood projected at each systole is generally estimated at six ounces. The causes of the alternate contraction and relaxation are entirely involuntary and dependent on the nervous system to a large extent. The systole of the ventricles is the cause of the motion of the blood in the arteries, which dilate with each wave driven into them.
The heart is the seat of various and generally dangerous diseases. One of these is pericarditis or inflammation of the pericardium, the double lining membrane or bag enveloping the heart. The cause of this disease may be exposure to cold, or an injury, or it may be complicated with other diseases. Inflammation of the inner lining is termed endocarditis.
Valvular disease is a common affection of the heart, the valves becoming thickened, contracted, rigid, or otherwise affected, so that they cannot properly perform their duty. The mitral valve, for instance, may become too narrow and contracted, and the result is that all the blood does not pass into the aorta. In other cases of valvular disease, the same result follows, that is imperfect depletion of the ventricles and auricles, the return of blood being termed regurgitation. The heart consequently becomes weakened, while the entire system suffers.
Overgrowth or hypertrophy and dilatation are frequent results of valvular disease. The use of digitalis is often successful in strengthening and soothing the heart. Certain diseases produce atrophy, in which the heart becomes feeble in action, while fatty degeneration occurs, when the muscular fibres are replaced by oleaginous particles. Research Heart
The veins of the liver are relatively large to accommodate the great volume of blood passing through it. The liver receives 28% of the body's total cardiac output of blood, which equates to 2 1/2 pints (1.4 liters) of blood circulating through an average adult at rest every minute. After passing through the liver, the blood leaves the liver by way of the hepatic vein, which drains into the inferior vena cava. Research Hepatic Vein
The external iliac is a continuation of the femoral vein. It extends upward along the pelvis eventually joining with the internal iliac to form the common iliac vein. The left common iliac and right common iliac veins converge to form the inferior vena cava. The
iliac veins receive blood from the lower extremities and pelvis. The external iliac contains one or two valves, while the internal iliac and common iliac veins do not have any. Research Iliac Vein
The portal vein is a large vein (a little over eight centimeters in length) responsible for carrying the oxygen and nutrient poor blood from the organs of the abdomen to the liver, where wastes will be eliminated. The portal vein enters the underside of the liver and divides into a network of capillaries. The capillaries then reconverge and form the hepatic veins that carry the blood to the inferior vena cava. The veins of the liver are relatively large to accommodate the great volume of blood passing through it. The liver receives 28% of the body's total cardiac output of blood, which equates to 1.4 liters of blood circulating through an average adult at rest every minute. Research Portal Vein
There are two renal veins, one extending from each lobe of the kidney, and opening into the vena cava. Cell waste is discharged in the veins for excretion through the kidneys. The body circulates about 425 gallons of blood through the kidneys on a daily basis, but only about a thousandth of this is converted in urine. The remainder goes back into circulation through the renal arteries. From the Bowman's capsule, the blood is carried through the compact network of capillaries that forms the glomerulus within the capsule. The capillaries eventually reconverge into small venules which lead to the larger renal veins. Research Renal Vein
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Bulbous Corydalis
