Human blood

Human blood is composed of several types of cells that have specific functions in the body. These cells are suspended in a liquid called plasma, which makes up about 55% of the volume of blood. The cells present in blood include red blood cells, white blood cells, and platelets.
Red blood cells, also known as erythrocytes, are the most abundant type of blood cells. Their primary function is to transport oxygen from the lungs to the tissues of the body and to carry carbon dioxide back to the lungs to be exhaled. Red blood cells are biconcave discs with a thin rim and a central depression, which gives them a doughnut-like shape. They contain a protein called hemoglobin, which binds to oxygen and carries it through the body. Red blood cells are produced in the bone marrow and have a lifespan of about 120 days.
White blood cells, also known as leukocytes, are responsible for protecting the body against infections and diseases. There are several different types of white blood cells, each with a specific function. For example, neutrophils are the most common type of white blood cell and are responsible for fighting off bacterial infections. Monocytes and macrophages are also types of white blood cells that help to destroy infected or damaged cells. Lymphocytes are another type of white blood cell that is involved in the immune response. They include T cells and B cells, which help to identify and attack foreign substances in the body. White blood cells are produced in the bone marrow and are released into the bloodstream when the body needs them.
Platelets, also known as thrombocytes, are small, irregularly shaped cells that are involved in the process of blood clotting. When a blood vessel is damaged, platelets aggregate at the site of the injury and form a clot to stop the bleeding. Platelets are produced in the bone marrow and have a lifespan of about 10 days.
In conclusion, human blood is composed of several types of cells that have specific functions in the body. Red blood cells transport oxygen and remove carbon dioxide, white blood cells protect against infections and diseases, and platelets help to stop bleeding. These cells work together to maintain the health and function of the body.