"heart" prevod sa engleskog na srpski

Množina: hearts

The hollow muscular organ whose rhythmic contractions pump blood through the body; SYN. pump, ticker.
Muscular organ that rhythmically contracts to force blood around the body of an animal with a circulatory system. Annelid worms and some other invertebrates have simple hearts consisting of thickened sections of main blood vessels that pulse regularly. An earthworm has ten such hearts. Vertebrates have one heart. A fish heart has two chambers—the thin-walled atrium (once called the auricle) that expands to receive blood, and the thick-walled ventricle that pumps it out. Amphibians and most reptiles have two atria and one ventricle; birds and mammals have two atria and two ventricles. The beating of the heart is controlled by the autonomic nervous system and an internal control center or pacemaker, the sinoatrial node.
the cardiac cycle.
The cardiac cycle is the sequence of events during one complete cycle of a heart beat. This consists of the simultaneous contraction of the two atria, a short pause, then the simultaneous contraction of the two ventricles, followed by a longer pause while the entire heart relaxes. The contraction phase is called “systole” and the relaxation phase which follows is called “diastole”. The whole cycle is repeated 70–80 times a minute under resting conditions.
When the atria contract, the blood in them enters the two relaxing ventricles, completely filling them. The mitral and tricuspid valves, which were open, now begin to shut and as they do so, they create vibrations in the heart walls and tendons, causing the first heart sound. The ventricles on contraction push open the pulmonary and aortic valves and eject blood into the respective vessels. The closed mitral and tricuspid valves prevent return of blood into the atria during this phase. As the ventricles start to relax, the aortic and pulmonary valves close to prevent backward flow of blood, and their closure causes the second heart sound. By now, the atria have filled once again and are ready to start contracting to begin the next cardiac cycle.
position and capacity.
The human heart is more or less conical in shape and is positioned within the chest, behind the breast bone, above the diaphragm, and between the two lungs. It has flattened back and front surfaces and is, in health, the size of a person’s closed fist. However, it varies in size with the person’s weight, age, sex, and state of health. Its capacity is about 20 cm3 in the newborn, reaching 150–160 cm3 in the mid-teens. The female heart has a smaller capacity and is lighter than the male.
internal structure.
The heart is enclosed by a strong membranous bag formed by the pericardium. It is inclined so that its tip (or apex) points left and downward. The point at which the stroke of the heart is most perceptible is called the “apex beat”. The organ is divided inside, into the left and right halves, by a longitudinal partition. Transverse constrictions further divide it into two chambers at the top and two at the bottom, the left and right atria and ventricles, respectively. Its blood supply comes from the left and right coronary arteries, arising from the root of the aorta. The heart is surrounded by fatty tissue in which may be found lymphatic vessels, nerves, and nerve endings. The inner surface of the cavity of the heart is lined by the endocardium.
atria and ventricles.
The atria are situated at the broader end of the heart which is at the top, and are thin-walled chambers that act as reservoirs, receiving blood from the veins. The two venae cavae, the major veins bringing back deoxygenated blood from the head, body, and limbs, join the right atrium. This chamber is separated from its respective ventricle by a valve with three flaps, the tricuspid valve. The right ventricle is a pyramidal chamber with thicker walls than the atria. The opening of the pulmonary artery, which leaves the right ventricle, has a valve that prevents the ejected blood from flowing back into the ventricle when it relaxes. The left atrium receives blood from the lungs via the four pulmonary veins, and transfers it into the left ventricle. This chamber has the stoutest walls of all, as its contraction should generate sufficient blood pressure to propel the blood into all the arteries of the body. The valve between the left atrium and ventricle has only two flaps and looks somewhat like a bishop’s miter.
, hence the name bicuspid or mitral valve. The aorta, the main artery of the body, springs from the left ventricle. Its orifice is guarded by the aortic valve.

Množina: hearts

ETYM Old Eng. harte, herte, heorte, AS. heorte.
(Homonym: hart).
1. The locus of feelings and intuitions; SYN. bosom.
2. The courage to carry on; SYN. mettle, nerve, spunk.<br /> 3. An inclination or tendency of a certain kind; SYN. spirit.
4. A playing card in the major suit of hearts.
5. A firm rather dry variety meat (usually beef or veal).
6. A shape with rounded sides curving inward at the top and intersecting at the bottom; conventionally used on playing cards and valentines.

Množina: heart attacks

Or myocardial infarction; Sudden onset of gripping central chest pain, often accompanied by sweating and vomiting, caused by death of a portion of the heart muscle following obstruction of a coronary artery by thrombosis (formation of a blood clot). Half of all heart attacks result in death within the first two hours, but in the remainder survival has improved following the widespread use of thrombolytic (clot-buster) drugs.
After a heart attack, most people remain in hospital for seven to ten days, and may make a gradual return to normal activity over the following months. How soon a patient is able to return to work depends on the physical and mental demands of their job. Despite widespread fears to the contrary, it is safe to return to normal sexual activity within about a month of the attack.
A sudden severe instance of abnormal heart function.

Množina: heart defects

Množina: heart diseases

A disease of the heart; SYN. heart condition, cardiopathy.
Disorder affecting the heart; for example, ischemic heart disease, in which the blood supply through the coronary arteries is reduced by atherosclerosis; valvular heart disease, in which a heart valve is damaged; and cardiomyophathy, where the heart muscle itself is diseased.

Množina: heart failures

Inability of the heart to pump enough blood to sustain normal bodily functions; SYN. coronary failure.
Condition arising when the heart's pumping mechanism is inadequate. It results in back pressure of blood, causing congestion of the liver and lungs, failure of the peripheral blood supply and edema. It may be a consequence of hypertension or various types of heart disease. Treatment is with a diuretic and heart drugs, especially digoxin. heart-failure

Množina: heart-to-hearts

A heart-to-heart conversation.

Množina: heartbeats

1. The beating of the heart.
2. A single beat of the heart.
3. A brief moment; an instant.
The regular contraction and relaxation of the heart, and the accompanying sounds. As blood passes through the heart a double beat is heard. The first is produced by the sudden closure of the valves between the atria and the ventricles. The second, slightly delayed sound, is caused by the closure of the valves found at the entrance to the major arteries leaving the heart. Diseased valves may make unusual sounds, known as heart murmurs.

1. Causing intense sorrow or distress.
2. Extremely trying or difficult.
3. Producing an intense emotional reaction or response.