The cardiovascular system is sometimes called the blood-vessels, or just the circulatory system. It has a heart, which is a device that pushes muscles, and a closed system of vessels called arteries, veins, and capillaries.
As the name implies, the blood contained in the circulatory system is pumped by the heart around a closed circle or the circulation of vessels as it constantly passes through the body’s “circuits”. As in the adult body, survival of a growing embryo depends on blood circulation maintaining homeostasis and a healthy cell environment.
In response to this need, the cardiovascular system makes its appearance early in growth and reaches a state of function long before any other organ system. Surprisingly as it seems, the old heart begins to beat regularly as early as the fourth week following fertilization.
The important role of the cardiovascular system in maintaining homeostasis depends on the continuous and controlled flow of blood through thousands of miles of capillaries that penetrate every tissue and reach every cell in the body. It is in the very small capillaries that the blood performs its final function of transport.
Nutrients and other essential nutrients pass from capillary blood to fluids that surround cells when waste products are removed. The various control methods help to control and integrate the various functions and components of the cardiovascular system to supply blood to specific areas of the body according to need.
These methods ensure a constant internal environment that surrounds every cell of the body regardless of the different nutrient requirements or production of waste products.
Features of the cardiovascular system
The cardiovascular system is the system responsible for sending blood to different parts of the body. It contains the following organs and tissues:
- Heart; A muscle pump that forces blood around the body.
- Closed vascular system; These arteries include.
- Arteries; The vessels that carry blood from the heart.
- Veins; The vessels that carry blood to the heart.
- Capillaries; The small arteries that extend from the arteries to supply blood to all body tissues. A reliable source.
There are two circulatory systems in the body.
- systemic circulatory system.
- pulmonary circulatory system.
Systemic circulatory system
Like physiology, the circulation of oxygenated blood vessels and the circulation of the lungs, diverts oxygen-free blood from body tissues. From the left ventricle of the heart, blood is pumped through the arteries and capillaries through the aorta and arterial branches, where it balances with the tissue fluid, and then goes back to the arteries through the vena cava.
The right atrium of the heart. The pressure in the arterial system is caused by the activity of the heart and is disturbed by the blood, which maintains proper blood flow. However, the system consists of several parallel circuits, each with its own arterial resistance, which determines blood flow independently and without undue interference.
For example, blood flow through the digestive tract increases after eating and increases through active muscles during exercise. See also pulmonary circulation.
Includes a large network of arteries, nerves, and lymph nodes that work to transfer blood and other fluid between the heart, lungs, and spine. They are designed to perform certain functions unique to the lung system, such as ventilation and gas exchange. The pulmonary circulation receives the total output of the heart from the right ventricle and is a low pressure, low resistance system due to its parallel capillary circulation.
Structure of the heart
The heart can be found in the middle of the chest, below the sternum on the chest part. It consists of four chambers and several valves that control the normal flow of blood within the body.
Two chambers called the atrium are located in the upper part of the heart and the left atrium receives oxygenated blood and the right receives oxygen-free blood. The valves separating these chambers are called atrioventricular valves, consisting of a tricuspid valve on the left and a mitral valve on the right.
The ventricles, on the other hand, are chambers located in the lower part of the heart; it pumps oxygen-rich blood to the organs of the body, reaching even the smallest cells. Similar to the atria, the valves also separate the ventricular chambers. Collectively called semilunar valves, these include pulmona and aortic valves.
The heart consists of three layers; the epicardium, the myocardium, and the endocardium. The inner wall of the heart is lined with endocardium. The myocardium contains heart muscle cells that form the central layer and a large part of the heart wall. The outer layer of the cell is called the epicardium, the second layer which is the structure of the layers that surround and protect the heart; allows for ample space for strong pushing, but also keeps the heart in place, reducing friction between the heart and other structures.
The heart has its own blood vessels that supply the heart muscle and blood. Arteries of the heart from the aorta, which surround the outer surface of the heart like a crown. It turns to capillaries where the heart muscle is supplied with oxygen before turning again into the coronary arteries to take oxygenated blood back to the right atrium, where blood will be supplied with oxygen through the pulmonary circulation.
Atherosclerosis is a blockage of the arteries and the accumulation of artificial fat. The heart muscle will die without a steady supply of blood; because of the narrow size of the coronary arteries and its function in serving the heart itself, atherosclerosis can be fatal in these arteries.
Decreased blood flow and subsequent deprivation of oxygen can lead to severe pain, known as angina. Complete vascular blockage will lead to myocardial infarction – death of heart muscle tissue – which is commonly known as a heart attack.
The function of heart
The function of the heart in any organism is to maintain a constant flow of blood throughout the body. This replenishes oxygen and circulates nutrients between cells and tissues.
The following are the main functions of the heart:
- It is one of the basic functions of the human heart is to pump blood to the body.
- Blood provides oxygen, hormones, sugar and other substances to various parts of the body, as well as the human heart.
- The heart also ensures that adequate blood pressure is maintained in the body
There are two types of circulation within the body, which are pulmonary circulation and systemic circulation.
- The external structure of the Heart
One of the first structures that can be considered when the external structure of the heart is viewed is the pericardium.
The human heart is located on the left side of the chest and is enclosed in a fluid-filled cavity described as a pericardial cavity. The walls and facial tissue are formed by a membrane known as the pericardium.
The pericardium is a membrane of fibers found as an outer covering around the heart. It protects the heart by releasing serous fluid, which lubricates the heart and prevents friction between the surrounding organs. In addition to lubrication, the pericardium also helps by keeping the heart in its position and by maintaining the empty space of the heart to expand when it is full.
The heart wall is made up of 3 layers, which are:
- Epicardium; Epicardium is the outer layer of the heart. It consists of a thin, smooth membrane that serves to smooth and protect the outer part.
- Myocardium; This is a layer of muscle tissue and is the wall of the middle layer of the heart. It contributes to obesity and is responsible for the pushing point.
- Endocardium; It is the innermost layer that covers the inner chambers of the heart and covers the heart valves. In addition, it prevents blood from sticking to the inner walls, thus preventing blood clotting.