Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: June 21, 2025
The introduction of fresh air into a room or building in such a manner as to keep the air within it in a pure condition. Belonging to the abdominal or belly cavity. Ventricles of the Heart. The two largest cavities of the heart. Worm-shaped. The backbone; also called the spinal column and spine. Vestibule.
To illustrate the effect of muscular exercise in quickening the pulse. Run up and down stairs several times. Count the pulse both before and after. Experiment 104. To show the action of the elastic walls of the arteries. Take a long glass or metal tube of small caliber. Turn the water on and off alternately and rapidly, to imitate the intermittent discharge of the ventricles.
Experimenting with a pigeon upon one occasion, after the heart had wholly ceased to pulsate, and the auricles too had become motionless, I kept my finger wetted with saliva and warm for a short time upon the heart, and observed that under the influence of this fomentation it recovered new strength and life, so that both ventricles and auricles pulsated, contracting and relaxing alternately, recalled as it were from death to life.
In those animals in which the ventricles of the heart are smooth within and entirely without fibres of muscular bands, or anything like hollow pits, as in almost all the smaller birds, the partridge and the common fowl, serpents, frogs, tortoises, and most fishes, there are no chordae tendineae, nor bundles of fibres, neither are there any tricuspid valves in the ventricles.
When the walls of the ventricles squeeze down to drive out their blood into the lungs and around the body, like all other muscles they harden as they contract and thump the pointed lower end, or apex, of the heart against the wall of the chest, thus making what is known as the beat of the heart, which you can readily feel by laying your hand upon the left side of your chest, especially after you have been running or going quickly upstairs.
In a somewhat parched voice Tom started to explain how this could come about, but in no time he was talking gibberish. "The aorta," he heard himself saying, "is the big main artery which comes out of one of the ventricles," and then he noticed the dazed look on the men's faces and, floundering hopelessly, managed to laugh it off.
The slender cords which regulate the valves are only just long enough to allow the folds to close together, and no force of the blood pushing against the valves can send them farther back, as the cords will not stretch The harder the blood in the ventricles pushes back against the valves, the tighter the cords become and the closer the folds are brought together, until the way is completely closed.
Great stress has been laid on the appearance of the heart; but, generally speaking, in nine cases out of ten, the heart of the rabid dog will exhibit no other symptoms of disease than an increased yet variable deepness of colour in the lining membrane of the ventricles.
In my younger days I visited Fairmount, and it was with a pious reverence that I renewed my pilgrimage to that perennial fountain. Its watery ventricles were throbbing with the same systole and diastole as when, the blood of twenty years bounding in my own heart, I looked upon their giant mechanism.
When the heart is hypertrophied in disease, the cavities of the ventricles are probably also generally enlarged, and therefore they propel more blood at each contraction than in normal persons and thus increase the blood pressure. The blood pressure is raised not only by intestinal toxemia and uremia, but also by lead poisoning and the conditions generally present in gout.
Word Of The Day
Others Looking