15.1 General characteristics of the cardiovascular system
15.2 Automatism of the heart
15.3 Excitability and conduction of excitation in the heart
15.4 Excitability and excitation of the heart
15.5 Contractility and contraction of the heart
15.6 Hormonal heart function
Profile materials Control questions Situational tasks
15.1. General characteristics of the cardiovascular system
Circulation is a physiological system that enables the blood to move within the cardiovascular system and ensures metabolism in organs and tissues. ?When I attend the autopsy of a person who died from heart disease, in one half of the cases I cannot understand why they have died, and in the other half of the cases, how he
could still live" (S.P. Botkin).
The main components of blood circulation system:
1) the heart; 2) vessels of systemic and pulmonary circulation; 3) blood; 4) neurohumoral regulation apparatus.
Role of the cardiovascular system in maintaining vital functions
The main functions of the cardiovascular system: 1) transport function: trophic, respiratory and excretory functions; 2) regulatory function - hormone transport, endocrine function of the vascular endothelium
and heart; 3) immune function - transport of antibodies, antigens, and WBCs; 4) afferent function - receptors of the heart and blood vessels; 5) thermoregula-tory function - transport of heat from the ?core" to the ?shell".
Blood circulation is an integrating system involved in maintenance of the body?s integrity.
Structural and functional characteristics of the heart (weight ≈300 g; 0.4% of body weight).
The heart chambers: the atria and ventricles form two consecutive pumps. The right heart provides for blood flow through the lungs (pulmonary circulation). The left heart provides for the systemic circulation.