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ФИО авторов:
Tlegenov Nurlanbek
Student of the Faculty of Natural Sciences of Nukus State Pedagogical Institute
Nametullaeva Juldiz
Student of the Faculty of Natural Sciences of Nukus State Pedagogical Institute
Название публикации:
«ANATOMICAL STUDY OF THE CIRCULATORY
SYSTEM»
The circulatory system includes the coronary arteries, capillaries, veins, and
lymphatic vessels. The heart and blood vessels ensure the uninterrupted movement of
blood in the human body. As a result of the heart's automatic contraction and dilation,
blood travels through the great arteries and capillaries to all tissues and cells in the
body, and then back to the heart through the small, medium, and large veins. arterial
blood, rich in substances, oxygen, hormones, is pumped into the aortic artery. It travels
through large, medium, and small arteries to the capillaries between tissues and cells.
Nutrients, oxygen and hormones in the blood pass into the cells.
Residual substances and carbon dioxide formed as a result of metabolism in the
cells pass from them to the small veins, capillaries, and then through the middle, large
veins to the right compartment of the heart. Thus, the cardiovascular system delivers
nutrients and oxygen to all the tissues and cells of the body. It receives the residual
substance formed in them and delivers it to the digestive organs. That is why the
cardiovascular system is also called the carrier system.
The cardiovascular system plays the most important vital function. If the heart
stops for a short time, a person’s life will also stop.
The cardiovascular system is made up of several parts, as mentioned above. In
order to study the functioning of this system perfectly, it is expedient to get acquainted
with the structure and function of each of its parts.
The structure and location of the heart. The heart is a central part of the circulatory
system and is a hollow organ made up of muscles. The size of each person’s heart is
close to a fist. People who engage in physical activity and sports have a well-developed
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heart muscle, which is larger than the heart of others. Heart mass is 220-300 g in men
and 180-220 g in women.
The heart is located in the chest, behind the sternum, between the two lungs, and
most of it is on the left side of the chest cavity. It is separated from the spine by the
posterior part of the esophagus and the descending part of the aortic artery. On the
lower side, it is separated from the abdominal cavity by a diaphragm (Fig. 3). The heart
wall consists of three layers: inner - endocardium, middle - muscle, ie myocardium,
and outer - pericardium. The outer membrane of the pericardium is two layers, and the
inner layer is attached to the heart muscle, which is called the epicardium. The outer
layer surrounds the heart as a bag. There is fluid in the space between the layers, which
facilitates the contraction and expansion of the heart.
The heart is made up of four chambers: the right and left ventricles, the right and
left ventricles. The wall of the ventricle is thinner, the ventricles, especially the wall of
the left ventricle, are thicker because the left ventricle pushes blood into the aorta with
high pressure and supplies blood to all organs and tissues of the body through a large
circulatory system. The heart has four valves (valves), a bicuspid valve between the
left ventricle and the left ventricle, a bicuspid valve between the right ventricle and the
right ventricle, and an aorta with a left ventricle. between and between the right
ventricle and the pulmonary artery are hemispherical valves. The heart valves are
designed in such a way that the blood moves in only one direction, that is, from the
compartments of the blood to the ventricles, and from them to the aorta and pulmonary
arteries.
The heart, as mentioned above, is the central organ of the circulatory system,
which, like a pump, continuously moves the blood in the arteries and supplies all the
organs, tissues, and cells of the body with nutrients and oxygen. Through its chambers,
5 I blood passes through an adult in a minute, but the heart does not use a single drop
of this blood for its own needs. The heart muscle is supplied with blood through two
special coronary arteries. These vessels separate from the initial part of the aorta and
enter between the heart muscles. The blood in the arteries supplies the heart muscle
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with nutrients and oxygen and turns into venous blood, which forms two coronary veins
and flows into the right ventricle of the heart. In an adult, 200-250 ml of blood per
minute travels to the heart muscle through the coronary arteries of the heart at rest.
when exercising, the amount of this blood increases to 800-1000 ml.
In one day and night, 500 I of blood flows through the coronary arteries through
the heart muscle.
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