The heart is a powerful muscular organ located in the chest, slightly left of the center. Its main function is to pump blood throughout the body, providing oxygen and nutrients to the cells and removing waste products. Here’s an overview of how the heart works:
- Blood Circulation: The heart is divided into four chambers: two upper chambers called the atria and two lower chambers called the ventricles. Blood flows through a series of blood vessels in a closed loop, known as the circulatory system.
- Deoxygenated Blood: Blood returning from the body, low in oxygen and rich in carbon dioxide, enters the right atrium through two large veins called the superior and inferior vena cava. When the right atrium contracts, it pushes the blood into the right ventricle.
- Pulmonary Circulation: From the right ventricle, the blood is pumped into the pulmonary artery, which carries it to the lungs. In the lungs, carbon dioxide is exchanged for oxygen through the thin walls of the capillaries surrounding the alveoli. Oxygenated blood returns to the heart through the pulmonary veins and enters the left atrium.
- Oxygenated Blood: When the left atrium contracts, it pushes the oxygenated blood into the left ventricle.
- Systemic Circulation: From the left ventricle, the blood is pumped into the aorta, the largest artery in the body. The aorta branches into smaller arteries that deliver oxygen-rich blood to all parts of the body’s tissues and organs.
- Cardiac Cycle: The heart’s pumping action is coordinated by electrical signals generated by the sinoatrial (SA) node, often referred to as the “natural pacemaker.” The SA node sends electrical impulses that cause the atria to contract, pushing blood into the ventricles. The impulses then travel to the atrioventricular (AV) node, which delays the signal slightly before transmitting it to the ventricles. This delay allows the ventricles to fill completely before they contract, pumping blood out of the heart.
- Heartbeat: The rhythmic contraction and relaxation of the heart chambers create a heartbeat. The lub-dub sound heard during a heartbeat corresponds to the closing of the heart valves. The “lub” sound is produced by the closure of the atrioventricular valves (tricuspid and mitral), while the “dub” sound is caused by the closure of the semilunar valves (aortic and pulmonary).
- Regulation: The heart rate and strength of contractions can be influenced by the autonomic nervous system. The sympathetic nervous system increases heart rate and contractility in response to stress or physical activity, while the parasympathetic nervous system slows down the heart rate during rest.
Overall, the heart’s efficient pumping action ensures a continuous flow of oxygenated blood to meet the body’s metabolic demands and maintain proper functioning of all organs and tissues. Maintaining a healthy lifestyle, managing stress, and avoiding risk factors can contribute to optimal heart function and overall cardiovascular health.
The human heart acts like a pump sending blood around your body to keep you alive. It’s a muscle the size of your fist, leaning slightly to the left in the middle of your chest.
What is the function of human heart?
Each day, your heart beats about 100,000 times. It continuously pumps about five liters (eight pints) of blood around your body through a network of blood vessels called your circulatory system. This blood carries oxygen and nutrients to all parts of your body to help your organs and muscles work properly. Your blood also carries away unwanted carbon dioxide and waste products.
What is the structure of human heart?
Your heart has a left side and a right side, separated by a thin muscular wall called the septum. Your heart has an upper chamber and a lower chamber on either side.
The upper chambers are called the left atrium and the right atrium (or atrium).
The lower chambers are called the left ventricle and the right ventricle.
The right side of your heart receives the deoxygenated blood that has just been circulated around your body. It pumps blood to your lungs to collect a fresh supply of oxygen. The left side of your heart pumps the reoxygenated blood around your body.
Your heart muscle is made up of three layers of tissue: heart chamber diagram.
Pericardium – a thin, outer layer that protects and surrounds your heart.
Myocardium – a thick, muscular middle layer that contracts and relaxes to pump blood around your heart.
Endocardium – a thin, inner layer that lines the four chambers and valves in your heart.
What does the electrical system of the heart do?
Your heart’s electrical system tells your heart when to contract and when to relax in order to pump your blood regularly. The instructions to contract and relax are given by electrical signals.
Electrical signals are sent from the sinus node, which is called your heart’s natural pacemaker. Usually, the sinus node sends electrical signals at a constant rate, but the rate can change depending on your emotions and if you’re active or at rest – so is your heart rate.
How does blood flow through the heart and around the body?
Your heart is connected to the rest of the circulatory system through blood vessels called arteries and veins.
Your arteries carry oxygen-rich blood from the heart to other areas of your body.
your veins return deoxygenated blood from your organs back to your heart
Your arteries and veins are connected by even smaller blood vessels called capillaries.
Your blood flows in one direction between your heart and the rest of your body, like a one-way traffic system. Your heart’s valves control the direction of your blood flow, they act like doors that open and close with each beat.
There are four valves in your heart, they are:
tricuspid valve and pulmonary valve on the right side of the heart
The mitral valve and the aortic valve on the left side of your heart.
Like the rest of your body, your heart needs a supply of oxygen-rich blood to function properly. Coronary arteries are the arteries responsible for supplying oxygenated blood to the heart. The coronary arteries extend to the outside of the heart to deliver blood.
How do your heart and lungs add oxygen to your blood?
Your blood flows through your heart and lungs to be reoxygenated before being pumped to the rest of your body. Oxygen gets added to your blood in four main steps, they are:
The right atrium receives the low-oxygen blood that has just been circulated around the body. The right atrium pumps the blood into the right ventricle.
The right ventricle pumps the low-oxygen blood to the lungs to pick up a fresh supply of oxygen.
The left atrium receives high-oxygen blood from the lungs and pumps it into the left ventricle.
The left ventricle pumps the high-oxygen blood to the rest of the body.
What are heart and circulatory diseases?
Sometimes the heart and circulatory system don’t work as they should, which can lead to heart and circulatory diseases (also called heart disease). We fund research on these conditions and their risk factors, including:
- Coronary heart disease (heart attack and angina)
- congenital heart disease
- inherited heart diseases
- the strokes
- vascular dementia
- diabetes.
What is causing your heart and circulatory system to malfunction?
problems with your heart and circulatory system, including heart attack or stroke, usually due to a gradual build-up of fatty material (called atheroma) in the arteries that surround the heart and supply blood to your brain It happens. blocked artery
The fatty material on the walls of the coronary arteries of the heart narrows the space for blood flow. When the arteries narrow and blood flow is restricted, the arteries cannot deliver enough blood to the heart and brain, which can lead to heart and circulatory diseases.
What puts me at risk for heart and circulatory disease?
Many heart and circulatory diseases share common risk factors, including
- poorly managed diabetes
- high blood pressure
- high cholesterol
- being overweight or obese
- smoking
- drinking too much alcohol
Heart and circulatory diseases can be worrying but the good news is that there are many things you can do now to reduce your risk of developing heart and circulatory diseases.