Systemic and Pulmonary System

Systemic and Pulmonary Circulations Summary Chart

* Pulmonary -> Blood going from the lungs to the heart via a Vein carries O2 and is CO2 poor. * Pulmonary -> Blood coming from the Heart to the Lungs via an Artery is O2 poor and CO2 rich. * Systemic -> Blood coming from the heart to the abdomen via an Artery is O2 rich and CO2 poor. * Systemic -> Blood coming from the abdomen to the heart via a Vein is O2 poor and CO2 rich.

Path of Blood Flow through the Heart

1. Right atrium (deoxygenated blood) 2. Right Ventricle 3. Pulmonary Trunk and Pulmonary Arteries 4. Pulmonary capillaries on the right and left lung 5. Pulmonary Veins (oxygenated blood) 6. Left Atrium 7. Left Ventricle 8. Aorta and Systemic Arteries 9 Systemic capillaries of head and upper limbs; systemic capillaries of the trunk and lower limbs 10 Superior Vena Cava, Inferior Vena Cava, Coronary Sinus

Systemic and Pulmonary Circulations Overview

The left side of the heart pumps oxygenated blood into the systemic circulation to all tissues of the body except the air sacs (alveoli) of the lungs. The right side of the heart pumps deoxygenated blood into the pulmonary circulation to the air sacs (alveoli) of the lungs.

Pulmonary Circulation

Pulmonary circulation is the movement of blood from the heart, to the lungs, and back to the heart again. This is just one phase of the overall circulatory system. The veins bring waste-rich blood back to the heart, entering the right atrium throughout two large veins called vena cavae. The right atrium fills with the waste-rich blood and then contracts, pushing the blood through a one-way valve into the right ventricle. The right ventricle fills and then contracts, pushing the blood into the pulmonary artery which leads to the lungs. In the lung capillaries, the exchange of carbon dioxide and oxygen takes place. The fresh, oxygen-rich blood enters the pulmonary veins and then returns to the heart, re-entering through the left atrium. The oxygen-rich blood then passes through a one-way valve into the left ventricle where it will exit the heart through the main artery, called the aorta. The left ventricle's contraction forces the blood into the aorta and the blood begins its journey throughout the body. The one-way valves are important for preventing any backward flow of blood. The circulatory system is a network of one-way streets. If blood started flowing the wrong way, the blood gases (oxygen and carbon dioxide) might mix, causing a serious threat to your body. You can use a stethoscope to hear pulmonary circulation. The two sounds you hear, "lub" and "dub," are the ventricles contracting and the valves closing.

Systemic Circulation

Systemic circulation supplies nourishment to all of the tissue located throughout your body, with the exception of the heart and lungs because they have their own systems. Systemic circulation is a major part of the overall circulatory system. The blood vessels (arteries, veins, and capillaries) are responsible for the delivery of oxygen and nutrients to the tissue. Oxygen-rich blood enters the blood vessels through the heart's main artery called the aorta. The forceful contraction of the heart's left ventricle forces the blood into the aorta which then branches into many smaller arteries which run throughout the body. The inside layer of an artery is very smooth, allowing the blood to flow quickly. The outside layer of an artery is very strong, allowing the blood to flow forcefully. The oxygen-rich blood enters the capillaries where the oxygen and nutrients are released. The waste products are collected and the waste-rich blood flows into the veins in order to circulate back to the heart where pulmonary circulation will allow the exchange of gases in the lungs. During systemic circulation, blood passes through the kidneys. This phase of systemic circulation is known as renal circulation. During this phase, the kidneys filter much of the waste from the blood. Blood also passes through the small intestine during systemic circulation. This phase is known as portal circulation. During this phase, the blood from the small intestine collects in the portal vein which passes through the liver. The liver filters sugars from the blood, storing them for later.