5.Серцево-судинна та респіраторна системи

• Where is the heart located?

It is located on the diaphragm between the lower borders of the lungs, occupying the middle of the mediastinum.

• What does each half of the heart consist of?

Each half consists of an upper chamber, called an atrium, and a larger lower chamber, called a ventricle

• What is the function of the right atrium?

The right atrium receives deoxygenated blood from the entire body via 2 large veins called the venae cavae. This blood is transferred to the right ventricle and pumped to the lungs via the pulmonary artery to be oxygenated and to lose carbon dioxide

• What is the function of the left atrium?

The left atrium of the heart receives oxygenated blood from the lungs (via the pulmonary veins); this blood is transferred to the left ventricle and then pumped to all tissues in the body.

• What is systole?

Each cardiac cycle consists of three phases: physiologists have called the first phase of short contraction of both atria — the atrial systole. They have called the second phase of a more prolonged contraction of both ventricles — the ventricular systole

• What is diastole?

The period of rest of the cardiac muscle is called the diastole

• What is the cardiac cycle composed of?

It composed of systole and diastole.

• What does the rate of heart beat depends on?

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

• How many beats per min does the heart make?

Physiologists have determined that in the adult the heart makes from 60 to 72 beats per minute

• What is blood?

Blood is a reddish bodily fluid that is pumped by the heart through the arteries and veins

• What is blood composed of?

It is composed of blood cells floating in blood plasma

• What are the functions of red blood cells?

The primary function of red blood cells is to transport oxygen from the lungs to the cells of the body.

• What are the functions of white blood cells?

White blood cells (WBCs), or leukocytes, are a part of the immune system and help human bodies fight infection

• What are thrombocytes responsible for?

Thrombocytes, also called platelets, are responsible for blood clotting (coagulation)

• What is blood plasma?

Plasma is a fluid that is the blood's liquid medium.

• How many blood groups do you know? Name them.

There are 4 blood groups: A, B, AB, O (ABO system). They can be Rh+ or Rh-.

• What may happen when blood groups between the donor blood and the recipient are not compatible?

If they are not compatible, the red blood cells from the donated blood will clump or agglutinate.

• What are the differences in human blood due to?

The differences in human blood are due to the presence or absence of certain protein molecules called antigens and antibodies. The antigens are located on the surface of the red blood cells and the antibodies are located in the blood plasma. Individuals have different types and combinations of these molecules. The blood group you belong to depends on what you have inherited from your parents.

• What are the two main ways to classify blood groups?

There are ABO and Rh systems.

• What are the main parts of the respiratory system?

There are 3 major parts of the respiratory system: the airway, the lungs, and the muscles of respiration.

• What is the function of the respiratory system?

The respiratory system provides oxygen to the body’s cells by removing carbon dioxide.

• What process takes place in the lungs?

Once oxygen enters the lungs, it's sent to the rest of the body's organs and tissues through a network of blood vessels

• Why is the left lung smaller than the right one?

The left lung is smaller than the right one due to location of heart near it.

• What is the respiratory system responsible for?

The respiratory system is responsible for supplying our body with oxygen

• What is the function of the nose?

We breathe oxygen through the mouth or nose, which warm up the gas and moisten it before it enters the rest of the body

• How do people expel foreign matters from the respiratory tract?

This foreign matter is expelled from the body through swallowing, coughing or sneezing.

• What do cilia do?

Cilia, which are very fine hairs, grow in the larynx, trachea and bronchi. These hairs are coated with mucus that captures any germs and pollutants that are in the air we breathe before it enters the lungs.

• What is hemoglobin?

Hemoglobin is an important transport molecule found in red blood cells that carries almost 99% of the oxygen in the blood.

• What is Sechenov famous for?

I.M. Sechenov (1829-1905) was a prominent Russian scientist, the founder of Russian physiology and scientific psychology. 106 scientific works were written by him. I. M. Sechenov isolated the blood gases and found out that most of the blood gases were combined with erythrocytes. I. M. Sechenov investigated the process of absorption of carbon dioxide by the solutions of salts