What is double circulation

• Much smaller than arteries and veins • Only one cell thick • Substances such as oxygen, glucose and carbon dioxide can diffuse through them • Blood is at very low pressure • Where gas exchange takes place - oxygen passes through the thin capillary wall and into the tissues, while carbon dioxide passes from the tissues into the blood The pulmonary circuit transports blood to the lungs. The blood is oxygenated there and then carried back to the heart. Exchange of oxygen and carbon dioxide happens in the lungs: • carbon dioxide diffuses from the blood into the air in the alveoli • oxygen diffuses from the air in the alveoli into the blood, and is absorbed by the red blood cells • Reminder : Unlike all other arteries and veins, the pulmonary artery carries deoxygenated blood and the pulmonary vein carries oxygenated blood. The heart is made of a special muscle called cardiac muscle which can tighten, or contract, regularly. It's job is to pump blood around your body. It is about the size of a clenched fist. Unlike the rest of your muscles, your heart expands and contracts, non-stop, all day and all night for your entire life without a break. About 38 million times a year! Without getting tired!! It pumps the blood which fills it up into arteries which carry the blood to the lungs or around the body. • the right side pumps blood through the pulmonary circuit to the lungs • the left side pumps blood through the systemic circuit to the rest of the body • the left side has thick...

Double Circulation A circulatory path is a path taken by the (Source: Wikipedia) Mechanism Of Double Circulation Double circulation is the most efficient way of In double circulation, there are two pathways in which blood flows. They are: • Pulmonary pathway • Systemic pathway. The pulmonary circulation or pathway carries the deoxygenated blood from the right side of the heart to the lungs. Exchange of Through the systemic circulation, oxygenated blood travels from the left side of the heart to the other areas of the body. At various organ sites, exchange of gases, nutrients, and waste through The pulmonary circuit and the systemic circuit work together. This ensures that deoxygenated blood goes to the lungs through the pulmonary artery while the oxygenated blood from the aorta reaches the different organs and Browse more Topics under Body Fluids And Circulation • • • • Capillary exchange (Source: Wikipedia) The arteries and veins have an extensive network throughout the body carrying oxygenated blood and deoxygenated blood. The smallest of these arteries and veins are connected each other through the capillaries. The capillaries at the arterial end allow Through the process of capillary exchange, oxygen leaves RBCs in the bloodstream and enters all the other cells of the body. Nutrients also diffuse out of the bloodstream into other These venous ends of the capillaries are connected with the smaller veins and venules, which join the larger veins. These veins now have deox...

Amanda Robb Amanda has taught high school science for over 10 years. She has a Master's Degree in Cellular and Molecular Physiology from Tufts Medical School and a Master's of Teaching from Simmons College. She is also certified in secondary special education, biology, and physics in Massachusetts. • Instructor A Walking Tour of the Heart Students often struggle to envision how the blood is actually flowing through double circulation. This activity seeks to address this as students create a walking tour of the circulation. This activity will require red and blue sidewalk chalk and a large space to draw outside, as students will draw a body, the lungs, and a diagram of the heart in colored chalk. Deoxygenated parts of the circulation can be drawn in blue and oxygenated parts in red. Then, students will take themselves or a friend on a "walking" tour of the circulation and point out important structures that were taught in the lesson. Directions In this activity, you're going to act like a blood cell traveling through the double circulation of a human being. To create this "walking tour" you'll need red and blue sidewalk chalk and a large space to draw. Follow the directions below to draw out the circulation, then lead a friend on a walking tour through your work. • Start by drawing a graphic heart in the center of your space. • Divide the heart into four sections and label each of the different chambers of the heart. Use red for chambers that have oxygenated blood and blue ...

To understand the critical importance of the heart requires taking a step back so we understand the needs of each cell in our body. Remember that our body is composed of over 10 trillion cells that work together in remarkable unity (a lesson in good governance!). Cells have basic needs, and at the top of the list would be these four things: The lungs are composed of a few hundred million tiny air sacs called alveoli, each of which are surrounded by a network of blood vessels (capillary bed) which carry deoxygenated blood, shown in blue, and carry out oxygenated blood, shown in red. (Adapted from Wikipedia image)Now let’s follow a single breath of air. 21% of the molecules in this breath are oxygen molecules, and as they race down into the lungs, they end up in the alveoli which are tiny air-filled sacs. The story could end there, if not for the remarkable nature of lungs. The lungs allow the oxygen molecules to continue their journey from the gas phase into a new liquid phase. Meanwhile carbon dioxide molecules make the opposite trip from liquid to gas similar to what happens at the surface of a carbonated beverage. The oxygen diffuses (think of the drop of ink in a pool of water) into the fluid interstitial space of the lung, and is then absorbed into the blood stream, and then enters into the red blood cells themselves. This diffusion occurs in a fraction of a second because the distance between the alveoli and the red blood cell is so tiny. The white balls start out on ...