Question

Write a description of how blood moves through the body. In your answer, be sure to include the   

       following:

-Involved anatomical structures of the heart

-What role veins, arteries and lungs play in the process

-Description and details of any involved systems or circuits

Answer 1

There are 2 types of circulation mainly:

• Pulmonary circulation (to the lungs)and
• Systemic circulation(to body organs)

Pulmonary circulation

When the right ventricle contract, the deoxygenated blood from the right ventricle enters to the pulmonary artery through the semilunar valve and takes the blood into the lungs.As the blood goes through the lung, it is oxygenated by the gas exchange inside the lungs.The oxygenated blood enters back into the heart to the left atrium through the pulmonary vein.

Systemic circulation

The oxygenated blood enters the left ventricle when atrial contraction occurs: by the opening of the bicuspid valve present between the left atrium and ventricle.,When the ventricular contraction occurs, it enters into the aorta by opening of the semilunar valve.Then the blood travels through the large arteries into the various parts of the body.Then it branches to the smaller arteries and finally the arterioles near the tissues, where the oxygen and nutrients are delivered to the tissues and the waste material like CO2 are recieved.Then the Deoxygenated blood enters to the venules and go through the various veins ultimately reaching the superior and inferior vena cava taking the blood to the right atrium.The atrial contraction occurs and the blood enters to the right ventricle by the opening of the tricuspid valve.

The blood from aorta goes to arms via brachial artery carrying the oxygenated blood to arms. It becomes deoxygenated and drains to cephalic vein and ultimately to the superior venacaval.

The other blood from the aorta goes to the large arteries in the head; carotid arteries, which become Deoxygenated as go through the tissue and drains to jugular vein and ultimately drain to the superior vena cava to the right atrium.

The some of the blood from the aorta goes to the liver via hepatic artery and, the deoxygenated blood from the liver drains to the right atrium through the inferior vena cava.

The oxygenated blood goes to GIT via mesenteric artery, and it will become deoxygenated, but not directly drained into systemic circulation; instead it drains to the liver and from there it joins the hepatic vein. (Hepatic portal Circulation)

Some of the blood goes to kidney through the renal artery and drains to the inferior vena cava by the renal vein.

The blood goes down to the tissues of the leg and supplies oxygen via femoral arteries and drains back to the inferior vena cava via the femoral veins.

• 

  Superior vena cava - Right atrium - Tricuspid valve cross - Right ventricle - Pulmonary semilunar valve cross - Pulmonary artery - Lung (alveoli) - Receives oxygen - Pulmonary vein - Left atrium - Bicuspid valve cross - Left ventricle - Aortic semilunar valve - Aorta - to body tissues

  Right side

  Inferior vena cava and superior vena cava are the main veins that bring the blood into the right atrium of the heart from the tissues.There is another opening that opening into the right atrium called coronary sinus.There is a hole found between the right atrium & the left atrium(during birth). This foramen ovale will be turned into the scar tissue during the development called fossa ovalis. SA node is found (a bunch of neural cells) found near the right atrium which help in the cardiac rhythm.

  Left side

  The left pulmonary veins bringing oxygenated blood from the left lung, and the right pulmonary veins drain the oxygenated blood from the right lung to the left atrium.

  Valves:

  Tricuspid valve are found in between the right atrium and ventricle. The bicuspid (mitral )valve is found in between the left atrium and ventricle.There are collagen structures that connects the valves to the inner wall of the ventricle called chorda tendinae. The papillary muscles are found on the inner wall of the ventricle upon which the chorda tendinae is attached.On contraction and relaxation of these muscles, These chorda tendinae will help the respective valves to open and close whenever needed.

  The right ventricle have to pump out the high volume of the blood into the pulmonary artery, where there is a valve present in the opening of the pulmonary artery, called pulmonary semilunar valve. Another one that separating the left ventricle and the aorta called aortic semilunar valve. Both function to prevent the back flow of the blood from these vessels.

  The septum that separating the two ventricles is called the Interventricular septum.The septum present between the atriums is called interatrial septum.