Heart 

 Your heart is the main organ of your cardiovascular system, a network of blood vessels that pumps blood throughout your body. It also works with other body systems to control your heart rate and blood pressure. Your family history, particular health history and life all affect how well your heart works. 

 What's the heart? 

The heart is a fist sized organ that pumps blood throughout your body. It's the primary organ of your circulatory system. 

Your heart contains four main sections (chambers) made of muscle and powered by electrical impulses. Your brain and nervous system direct your heart’s function. 

 What's the heart’s function? 

• Your heart’s main function is to move blood throughout your body. 
• Your heart also controls the meter and speed of your heart rate. 
•  Maintains your blood pressure. 

 How does your heart work with other organs? 

 Your heart works with other body systems to control your heart rate and other body functions. The primary systems are Nervous system. Your nervous system helps control your heart rate. It sends signals that tell your heart to beat slower during rest and briskly during stress. 

 Endocrine system: Your endocrine system sends out hormones. These hormones tell your blood vessels to constrict or relax, which affects your blood pressure. Hormones from your thyroid gland can also tell your heart to beat briskly. 

 Where is your heart located? 

 Your heart is located in the front of your casket. It sits slightly behind and to the leftism of your sternum (breastbone). Your caricature pen protects your heart. 

 What side is your heart on? 

 Your heart is slightly on the left side of your body. It sits between your right and left lungs. The left lung is slightly lower to make room for the heart in your left casket. 

How big is your heart? 

 Everyone’s heart is a slightly different size. Generally, adult hearts are about the same size as two gripped fists, and children’s hearts are about the same size as one clenched fist. 

 How important does your heart weight? 

 On average, grown-up’s heart weight about 10 ounces. Your heart may weigh a little more or a little less, depending on your body size and coitus. 

 What are the corridor of the heart’s deconstruction? 

 The corridor of your heart are like the corridor of a house. Your heart has 

•  Walls. 
•  Chambers (apartments). 
•  Faucets (doors). 
•  Blood vessels (plumbing). 
•  Electrical conduction system (electricity). 

 Heart walls 

 Your heart walls are the muscles that contract (squeeze) and relax to shoot blood throughout your body. A subcaste of muscular towel called the septum divides your heart walls into the left and right sides. 

 Your heart walls have three layers, 

•  Endocardium Inner subcaste. 
•  Myocardium Muscular middle subcaste. 
•  Epicardial Defensive external subcaste. 

 Epicardial is one subcaste of your pericardium. The pericardium is a defensive sac that covers your entire heart. It produces fluid to slick your heart and keep it from rubbing against other organs. 

Heart chambers 

 Your heart is divided into four chambers. You have two chambers on the top (patio, plural gallerias) and two on the bottom (ventricles), one on each side of the heart. 

1.  Right patio Two large modes deliver oxygen-poor blood to your right patio. The right patio pumps the blood to your right ventricle. 
2.  Right ventricle The lower right chamber pumps the oxygen-poor blood to your lungs through the pulmonary roadway. The lungs reload blood with oxygen. 
3.  Left patio After the lungs fill blood with oxygen, the pulmonary modes carry the blood to the left patio. This upper chamber pumps the blood to your left ventricle. 
4.  Left ventricle The left ventricle is slightly larger than the right. It pumps oxygen-rich blood to the rest of your body. 

 Heart faucets 

 Your heart faucets are like doors between your heart chambers. They open and close to allow blood to inflow through. The atrioventricular (AV) faucets open between your upper and lower heart chambers.

They include 

•  A Tricuspid stopcock Door between your right patio and right ventricle. 
•  Mitral stopcock Door between your left patio and left ventricle. 
•  Semilunar (SL) faucets open when blood flows out of your ventricles.

They include 

•  Aortic stopcock Opens when blood flows out of your left ventricle to your aorta (roadway that carries oxygen-rich blood to your body). 
•  Pulmonary stopcock Opens when blood flows from your right ventricle to your pulmonary highways (the only highways that carry oxygen-poor blood to your lungs). 

 Blood vessels 

1.  Your heart pumps blood through three types of blood vessels. 
2. Highways carry oxygen-rich blood from your heart to your body. 
3. The exception is your pulmonary highways, which go to your lungs. 
4. Modes carry oxygen-poor blood back to your heart. 
5. Capillaries are small blood vessels where your body exchanges oxygen-rich and oxygen-poor blood. 

 Your heart receives nutrients through a network of coronary highways. These highways run along your heart’s face. They serve the heart itself. 

 Electrical conduction system 

 Your heart’s conduction system is like the electrical wiring of a house. It controls the meter and pace of your twinkle. It includes

•  Sinoatrial (SA) knot, sends the signals that make your heart beat. 
•  Atrioventricular (AV) knot Carries electrical signals from your heart’s upper chambers to its lower bones. 

 Your heart also has a network of electrical packets and filaments. This network includes 

•  Left pack branch sends electric impulses to your left ventricle. 
•  Right pack branch sends electric impulses to your right ventricle.