Human Circulation at a Glance
The human body has several different processes that happen at the same time. These processes are vital in our body to happen to keep us alive.
The circulation of blood in a human body is essential to have enough oxygen to reach different cells. This particular oxygen is then used by our cells for other purposes, including respiration. Respiration is a critical process in our human body to carry out various life functions.
This image above shows a circular human system. The human circulatory system is an intricate network of arteries, capillaries, and veins. Our heart is a fist-sized organ that is located in our rib cage, and slightly tilted towards the left. It is an organ that pumps blood from our body.
Composition of the Human Circulatory System
We can classify these tissues into two parts, Meristematic Tissues, and Permanent Tissues.
The human circulatory system comprises very vital organs with various functions to perform.
These important organs are:
Heart: The heart is a four-chambered organ that is present inside our rib cage. It is the size of our first and is made up of special muscles known as cardiac muscles.
The upper two chambers of the heart are called The Auricles and lower chambers are known as Ventricles.
Human beings have a complex circulation which is also known as a double circulation. In this circulation the blood flows through the heart two times.
This type of circulation is vital for our body as our human body is larger than other animals and needs oxygen-rich blood to flow throughout the body.
It is divided into four chambers by a division known as the septum. In this structure of the heart, the left side has pure oxygenated blood flowing through it, whereas the right side carries the deoxygenated or the carbon dioxide-rich blood. Among the auricles and the ventricles, one valve is there on each side.
The valves are responsible for the unidirectional flow of blood. When the blood flows through the ventricles, these valves close up so that there is not any backflow.
There is a lub-dub sound that is produced as these valves open and close. This sound is known as the heartbeat.
Lymphatic System: Our human body has other fluids than the blood; these are called lymph. They are a tissue just like the blood, but it is a colorless liquid that is responsible for transporting fats and absorbed foods to intercellular areas.
Blood: Speaking of fluids in our body, Blood is the most important one. It is not an organ but a connective tissue that has a composition of blood cells, plasma, floating proteins and other minerals.
Blood is made up of different types of cells, platelets, and plasma:
Plasma is the fluid content of the blood which makes about 90% of its structure.
Red Blood Cells (RBCs): They are also known as Erythrocytes and transport oxygen to our entire body. They contain the important protein Haemoglobin, which when combined with Oxygen, creates a compound called Oxyhaemoglobin.
People with a higher amount of Haemoglobin are usually more active because oxygen reaches all parts of their body quickly, which as a result, produces more energy.
White Blood Cells (WBCs): They are also known as Leukocytes and are responsible for forming our body's defense mechanism. These blood cells help us fight against foreign pathogens and build up our immunity.
Platelets: They are also called Thrombocytes, and help during an energy to create blood clots so that excessive blood does not flow out of our body.
Blood Vessels: Blood Vessels are tube-like structures responsible for the flow of blood in the body. There are two types of blood vessels present in our body:
Arteries: They are responsible for carrying the oxygenated blood from our heart to other organs of our body. Blood flows through our arteries at tremendous pressure. This is the reason why our arteries have thick and elastic walls. They are located deep below our skin.
Veins: They are responsible for carrying the deoxygenated blood from the cells in our body back to the heart. The pressure of the flowing of blood in them is lesser than the arteries. They are located near the surface of our skin, and we can also see them in our bodies.
Functions of the Human Circulatory System
The human body has a complex circulatory system that has the following functions:
It maintains the blood supplied to all the organs of our body.
It transports nutrients like oxygen-carbon dioxide and hormones to various cells and organs.
It protects our body from any new disease-causing microorganisms.
FAQs on Human Circulatory System
1. What are the four main parts of the Human Circulatory System?
The Human Circulatory System works on three primary independent systems. These systems are the cardiovascular, pulmonary and systemic parts of our body.
The heart maintains our cardiovascular system, the lungs maintain our pulmonary system, and our arteries, veins, coronary and portal vessels maintain the systemic part of our human body.
It is the system that is responsible for the blood flow throughout our body, the nutrients, oxygen and other gasses that pass through our body, and the hormones to and from the cells.
2. What is the correct order of the blood flow in our circulatory system?
The correct order in which our blood flows through our circulatory system is as follows:
Firstly, our right ventricle pumps the oxygen-poor blood from the lungs through our pulmonary valve.
The left atrium will then receive this oxygen-rich blood from our lungs and pump it to the left ventricle through a valve called the mitral valve.
After this, the left ventricle makes this oxygen-rich blood flow through the aortic valve out to the rest of the human body.
The blood then flows throughout our body.
3. What is the location of our Heart?
The heart lies in the front and the middle of our chest. It is there in the behind and slightly to the left of our breastbone and it is the size of a human fist.
It is a muscle that pumps blood throughout our human body to provide it with important nutrients and hormones for proper functioning.
Our heart beats around 100,000 times a day and pumps about 9,000 Liters of blood everyday.
Our heart is separated into right and left parts by a wall.
4. What is the primary distinction between White Blood Cells and Red Blood Cells?
The Red Blood Cells (RBCs) and The White Blood Cells (WBCs) are both extremely vital for the human body.
The main difference is between the functions that they both perform. Where the Red Blood Cells carry the oxygen to different parts of our body. The White Blood Cells are responsible for creating a defense mechanism in our body and generate antibodies.
We can call the RBCs the Carriers, on the other hand, the WBCs are the Protectors inside our body.
5. Are there other concepts related to our Human Body available on Vedantu?
On this page, we studied about the human circulatory system, its composition and functions. You can find plenty of other material related to the subject of the human body right here at Vedantu's app and website. This study material is curated by experts to help a student learn about these concepts easily.
Students can utilize the live lecture and micro-lessons which are designed to facilitate their pace of learning. We also provide study material like mock tests, questions papers, important questions and syllabus structures for students to download as PDFs for offline use.
6. Explain The Difference Between The Pulmonary Artery And Pulmonary Vein?
Arteries carry oxygenated blood, while veins carry deoxygenated blood. However, the functions of the pulmonary artery and pulmonary vein are entirely different. The pulmonary artery carries deoxygenated blood while pulmonary veins carry oxygenated blood.
Pulmonary veins bring oxygenated blood from the lungs to the left auricle. The pulmonary artery takes the deoxygenated blood from the right ventricle to the heart back to the lungs
7. Explain the entire process of circulation in the human body?
Process of circulation: We breathe in oxygen, which reaches the lungs. Inside every lung, tiny air sacs called alveoli are present. These alveoli are richly supplied with blood vessels. Here, the oxygen moves from the lungs to the blood. Through the pulmonary vein, the oxygen-rich blood enters the left auricle. The valve opens and this blood is pumped into the left ventricle. From here, the blood flows to the mother artery (aorta) after which, the blood is supplied to various organs of the body through a network of other arteries. Carbon dioxide formed as a product of respiration by the cells returns back to the heart. The carbon dioxide-rich blood enters the right auricle and is pushed into the right ventricle. The pulmonary artery takes this deoxygenated blood from the right ventricle to the lungs. Again, an exchange of gas takes place and carbon dioxide moves out of the blood into the lungs, after which it is exhaled through the nose.
