Red blood cells contain a protein called hemoglobin that takes up and releases oxygen in response to the environment around it. Hemoglobin is what's called a "metalloprotein" because it incorporates atoms of iron into its structure. This iron is positively charged and readily binds with oxygen. In oxygen-poor environments, the hemoglobin releases the oxygen it carries and picks up carbon dioxide.Know More
When hemoglobin is exposed to high oxygen concentrations, such as in the lungs, it flexes open to expose its iron atoms to the oxygen. After binding with oxygen, the hemoglobin is carried by red blood cells to various parts of the body. These destination sites are poor in oxygen, and the differential induces the hemoglobin protein to shed its oxygen. The ionized iron is then exposed and eager to bond with carbon dioxide. The hemoglobin holds this waste gas securely until the red blood cell is transported back into the oxygen-rich environment of the lungs, where the cycle repeats and more oxygen is taken up.
Around 25 percent of the cells in the human body are red blood cells, with 2.4 million of them produced every second. Each red blood cell contains around 270 million hemoglobin molecules, circulates through the body once every 20 seconds, and lasts between 100 and 120 days before breaking down.Learn more about Blood
The red color of blood comes from the hemoglobin that makes up the majority of the mass of the cell, which allows the blood cell to carry oxygen around the body. The plasma itself is a straw color when viewed under a microscope, but the hemoglobin makes up so much of the blood cell that its red color overpowers the color of the plasma. When a red blood cell is full of oxygen, the red has a scarlet tint to it, when it has released it's oxygen its more of a dark burgundy color.Full Answer >
Blood in humans is red, not blue. It is a misconception that human blood is blue and turns red upon touching oxygen in the air.Full Answer >
A vein is a blood vessel that carries blood toward the heart. There are four main types of veins: pulmonary and systemic, and superficial and deep.Full Answer >
Blood platelets are cells that aid in the clotting process, according to the American Red Cross. They collect at the lining of the blood vessels in the event of a cut and help stop the flow of blood.Full Answer >