The human circulatory system

However, Harvey was not able to identify the capillary system connecting arteries and veins; these were later discovered by Marcello Malpighi in In this way, the body controls how much blood flows to different parts of the body under varying circumstances.

To avoid any injury or trauma, the heart is encompassed with a protective sac called the pericardium. An adult woman has approximately 5 liters of blood and a man has approximately 6.

The shape of erythrocytes is biconcave—disks with a concave curve on The human circulatory system sides of the disk so that the center of an erythrocyte is its thinnest part. Contraction of the ventricle then closes the tricuspid valve and forces open the pulmonary valve.

Pulmonary circulation transports deoxygenated blood from the right side of the heart to the lungswhere the blood picks up oxygen and returns to the left side of the heart. There are two major classes of white blood cells: This artery performs the function of transporting blood from the heart to the entire body.

Blood is made up of red blood cells, white blood cells, platelets, and liquid plasma. The sympathetic fight or flight division of the autonomic nervous system causes vasoconstriction, which leads to increases in blood pressure and decreases in blood flow in the constricted region.

Because blood pools in the veins after death, arteries look empty. Blood vessels can also affect blood pressure. Organs of the Circulatory System There are three basic organs of the circulatory system. In an adult male the heart weighs approximately gm. The Greek physicianHerophilusdistinguished veins from arteries but thought that the pulse was a property of arteries themselves.

Cardiovascular System

The heart pumps oxygenated blood to all the organs of the body and sends back de-oxygenated blood back to the lungs. In arthropodsthe open circulatory system is a system in which a fluid in a cavity called the hemocoel bathes the organs directly with oxygen and nutrients and there is no distinction between blood and interstitial fluid ; this combined fluid is called hemolymph or haemolymph.

For example, the brachiocephalic artery carries blood into the brachial arm and cephalic head regions. Note that the blood draining the stomach, spleen, and intestines passes through the liver before it is returned to the heart.

Sponsors Human Circulatory System Also known as cardiovascular or double circulatory system that is responsible for the transportation of oxygen, carbon dioxide, nutrients and other products of metabolism through three separate pulmonary, coronary and systemic circuits. The circulatory system works thanks to constant pressure from the heart and valves throughout the body.

These blood vessels carry the impure blood from the heart to the lungs and the purified blood back to the heart to be transported to various organs of the body. As skeletal muscles in the body contract, they squeeze nearby veins and push blood through valves closer to the heart. Cardiovascular System Physiology Functions of the Cardiovascular System The cardiovascular system has three major functions: If the area is not too large, the undamaged part of the heart can, in time, compensate for the damage.

Human Circulatory System

If you want to know the size of your heart, clench your fist. Contraction of the ventricle closes the mitral valve and opens the aortic valve at the entrance to the aorta.The circulatory system is a vast network of organs and vessels that is responsible for the flow of blood, nutrients, hormones, oxygen and other gases to and from cells.

Without the circulatory system, the body would not be able to fight disease or maintain a stable internal environment — such as proper temperature and pH — known as homeostasis. Human body.

Circulatory system

4 learner guides + 1 class clip. Find out how the heart keeps all the blood in your circulatory system flowing. 1 class clip. We have a selection of great videos for use in the.

Cardiovascular System Physiology Functions of the Cardiovascular System. The cardiovascular system has three major functions: transportation of materials, protection from pathogens, and regulation of the body’s homeostasis.

Transportation: The cardiovascular system transports blood to almost all of the body’s tissues. The blood delivers essential nutrients and oxygen and removes wastes and carbon. The circulatory system consists of three independent systems that work together: the heart (cardiovascular), lungs (pulmonary), and arteries, veins, coronary and portal vessels (systemic).

The system is responsible for the flow of blood, nutrients, oxygen and other gases, and as well as hormones to and from cells. The human circulatory system functions to transport blood and oxygen from the lungs to the various tissues of the body.

The heart pumps the blood throughout the body. The lymphatic system is an extension of the human circulatory system that includes cell. The remainder of the system is known as the systemic circulation.


The graphic shows the major arteries (in bright red) and veins (dark red) of the system. Blood from the aorta passes into a branching system of arteries that lead to all parts of the body.

The human circulatory system
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