In the systole phase of the cardiac cycle, the heart ventricles contract (beat) and pump blood into the arteries. Blood pressure readings measure systolic and diastolic pressures as the heart goes through the cardiac cycle. When platelets encounter an injured blood vessel, they clump together to block the opening in the vessel.īlood pressure is the force at which blood exerts pressure against artery walls as it circulates throughout the body. Fragments of the megakaryocytes circulate through the bloodstream and play a major role in clotting. Platelets (thrombocytes): These cell components are formed from pieces of cells found in the bone marrow called megakaryocytes.Examples include lymphocytes, monocytes, neutrophils, basophils, and eosinophils. There are several different types of white blood cells, each with different functions. These cells locate, destroy, and remove pathogens and foreign matter from the body. White Blood Cells (leukocytes): These cells play an important role in the immune system and lymphatic system by defending the body against infection.After depositing oxygen to tissue and organ cells, red blood cells pick up carbon dioxide (CO 2) for transportation to the lungs where the CO 2 is expelled from the body. These iron-containing proteins bind oxygen molecules obtained in the lungs and transport them to various parts of the body. Red blood cells do not have a nucleus, but they do contain millions of hemoglobin molecules. This flexible disc shape helps to increase the surface area-to-volume ratio of these extremely small cells. Both sides of the cell's surface curve inward like the interior of a sphere. Red blood cells have what is known as a biconcave shape. Red Blood Cells (erythrocytes): These cells determine blood type and are the most abundant cell type in the blood.Plasma also transports nutrients, sugars, fats, hormones, gases, and waste material contained within blood. Plasma contains salts, proteins, and blood cells.
![formed elements of blood formed elements of blood](https://reader020.vdocuments.site/reader020/slide/20190913/56649e875503460f94b8a8b9/document-16.png)
It consists of water with several different substances dissolved within. Plasma: This major constituent of blood comprises about 55 percent of blood volume.