Physiology of the human body Physiology of the cadiovascular system

I. Exercises.

ex. 1 Memorize the pronunciation of the following words:

total cardiac

ton systole

emotion diastole

regulate cadiovascular

ex. 2 Memorize the meaning of the following words:

pump - накачивать, нагнетать per - в, на, за

rate - частота, скорость per minute - в минуту

pulse rate - частота пульса depend (on, upon) - зависеть (от)

respiratory rate - частота дыхания wave - волна, колебание

beat (n) - толчок, удар, биение follow - следовать, соблюдать

beat (v) — бить(ся)б ударять(ся) exertion — напряжение, нагрузка

prolong (v) - продлевать on exertion - при напряжении (нагрузке)

prolonged - длительный estimate - определять, подсчитывать

discharge - выделять serve - служить

discharge from - выписывать send (sent, sent) - посылать, направлять

discharge out - выбрасывать considerable - значительный

ex. 3 Translate the word combinations:

on physical exertion, to be discharge from the hospital, to discharge out some blood, pulmonary circulation, to estimate the number of cells, to pump blood through the blood vessels, the total body weight, the period of rest, much higher

ex. 4 Translate into English:

1. чувствовать боль при физическом напряжении; to feel pain on physical exertion; 2. иногда физическое напряжение вызывает боль; sometimes physical exertion causes pain; 3. выбрасывать (выталкивать) кровь; to discharge out some blood; 4. она выписалась из больницы; she is discharged from the hospital; 5. малый круг кровообращения; pulmonary circulation; 6. большой круг кровообращения; systemic circulation; 7. периферическое кровообращение; peripheral circulation; 8. определят роль желудочков; to estimate the role of the ventricles; 9. медсестра подсчитала число клеток крови; the nurse has estimated the number of blood cells; 10. изменения зубцов электрокардиограммы зависят

от состояния работы сердца; the changes of the electrocardiogram waves depend on the condition of the heart activity

II. Text "Work of the Human Heart"

The human heart contracts from the first moment of life until the last one. The contractions of the heart pump the blood through the arteries to all the parts of the body. Scientists have determined that the total weight of the blood pumped by the heart daily is about ten tons.

The rate of heart contractions is regulated by two groups of nerve fibres. It varies in different persons and at different age.

Physiologists have determined that in the adult the heart makes from 60 to72 beats per minute. In children the rate of heartbeat is much higher. Research work of many scientists has helped to determine that the rate of heartbeat increases depending on different emotions.

Each beat of the heart is followed by a period of rest for the cardiac muscle. Each wave of contraction and a period of rest following it compose a cardiac cycle.

Research work has given physiologists the possibility to find out that the heart muscle works or contracts about one third of the time of the person's life. The period of rest is shorter during greater physical exertion and longer when the body is at rest.

Each cardiac cycle consists of three phases: the first phase of short contraction of both atria - the atrial systole; the second phase of a more prolonged contraction of both ventricles - the ventricular systole. The period of rest of the cardiac muscle is called the diastole.

The left ventricle discharges out the blood received by the left atrium from the pulmonary circulation through the aorta to the systemic circulation.

The blood received from the systemic circulation by the right atrium is discharged out of the right ventricle to the lungs through the pulmonary arteries.

Prolonged research work of many physiologists has given the possibility to estimate the role of the ventricles which serve as the main pump. The atria act as receiving chambers. The contraction of the atria which sends the final portion of the blood into the ventricle is considerably less.

III. Exercises.

ex. 1 Memorize the pronunciation of the following terms:

corpuscle flexibility

erythrocyte reservoir

leucocyte hemoglobin

thrombocyte maximal
elasticity

ex. 2 Memorize the meaning of the following words:

fluid - жидкость mild - мягкий, слабый, легкий

place — место range — колебаться; ряд, предел, область

take place - происходить meal - принятие пищи, еда

platelet - пластинка крови feature - характерная черта; особенность

exist - существовать, быть average - равняться в среднем

count - подсчет; подсчитывать volume - объем; емкость; том

mental - умственный, душевный, психический

sound - звук, тон; крепкий, здоровый; глубокий (о сне)

state - сообщать; констатировать, утверждать; состояние

to do (make) smb's blood count - делать (провести) подсчет клеток крови

ex. 3 Define parts of speech of the words in bold type; translate the sentences:

1. Please count from one to ten. 2. You must do the white blood cell count of this patient. 3. You must count how many days on an average we'll spend on this experiments. 4. What is the average temperature in the Crimea during August? 5. The doctor is going to discharge this patient from the hospital because his condition has become good. 6. Why does the wound continue to discharge much blood?

ex. 4 Translate the following indefinite personal sentences:

1. It is known that blood becomes oxygenated in the lungs. 2. They say that this patient's health will be restored soon. 3. One knows that pulse rate becomes rapid on physical exertion. 4. It is estimated that his body weight considerably decreased during the prolonged illness. 5. It is known that the increase of the number of leucocytes takes place when a person is ill. 6. They say that the Physiology Chair is going to form a students' scientific society. 7. It is determined that in the man the corpuscles form from 39 to 50 per cent of the blood volume. 8. It is considered that the first heart sound is the longest. 9. One can say that heart sounds are very important in making the diagnosis of a heart disease.

IV. Text "The Corpuscular Elements of Blood".

Blood is a fluid tissue with many various functions. Not only important physiological process takes place in the blood but it determines the activity of widely separated body cells.

Blood is composed of plasma and the corpuscular elements which are called red corpuscles or erythrocytes, white corpuscles or leucocytes and blood platelets or thrombocytes.

It is generally considered that no sex differences exist in the count of white corpuscles or leucocytes. The count of leucocytes in the blood of a healthy person is 4,500 to 9,500 per cu mm (cubic millimetre). When the number of white blood

cells is counted after mental or physical exertion, meals and mild activity it may increase.

The red blood cell count may change with age; when the red blood cell count is done after physical exertion and emotions it may increase.

One knows that red corpuscles have two physical features which are very important in the function of respiration. They have great elasticity and flexibility. These features give them the possibility to pass through very small capillaries. The discoid form of the corpuscle gives it a maximal surface for a given mass.

The most important part of the red cell is its red colouring substance or hemoglobin which on an average forms about 36% of its mass.

The total blood volume is divided into circulating and reservoir volumes.

The average human blood volume is not less than 7.5% but not more than 10% of the body weight. It is generally stated that the circulating volume averages smaller in the females than in the males. The circulating volume of the blood depends on the changes of the air temperature.

V. Text "The Heart Sounds"

When we listen to the heart we can hear two sounds. The third sound is also heard in some persons.

The first heart sound is the longest one. It is heard at the moment of contraction of the ventricles when the atrioventricular valves close.

The second sound lasts for a shorter period of time. It is heard at the moment when the pulmonary and aortic semilunar valves close.

The third sound is heard when the blood is passing from the atria into the ventricles.

The first sound and the second cardiac sounds are heard over all portions of the heart and often over the large vessels. The first heart sound is greater over the surface of the ventricles and it is the greatest over the surface of the mitral and tricuspid valves. The second heart sound is heard loudest over the aorta and the pulmonary artery.

Heart sounds are also heard over some portions of the chest. Normally the first heart sound is heard best over the apex of the heart in the fifth costal interspace. The second sound is heard best over the pulmonary artery and the aorta, that is in the second left and right costal interspaces. The aortic sound is normally louder than the pulmonic sound.

The heart sounds are very important in the clinical diagnosis and the doctors determine many cardiac diseases by heart sounds.