Anatomy – blood, blood vessels arteries veins and capillaries and heart
Physiology – the function of the cardiovascular system is Transportation – substances that are transported include respiratory gasses, nutrients from the digestive tract antibodies, waste materials and hormones from the endocrine glands as well as transportation of heat from active muscles to the skin, where the heat can be dissipated Protection – the body is protected through disease fitting white blood cells and removal of impurities and pathogens Combat hemorrhage – this is accomplished by clotting mechanism which prevent the loss of body fluids from damaged vessels.
BLOOD – blood transports nutrients to, and waste products from, individual cells. Blood is a fluid medium containing formed elements and liquid plasma. Formed elements are erythrocytes (Red Blood) leukocytes (white blood) and thrombocytes (platelets). Blood is classified as a liquid connective tissue and is essential for human life due to tissues getting oxygen and nutrients only from its blood supply a blood cell makes a round trip through the circulatory system every 60 seconds. Blood makes up 8% of total body weight; the average size person is approximately 5 l or 6 quarts or 12 pints of blood.
Hematopoiesis – is the process of blood cell development
Color of blood varies from bright scarlet red to dull maroon, depending on oxygen content.
COMPONENTS OF BLOOD
Erythrocytes – Red blood cells (RBC) primary function is to transport oxygen to cells , do not have a nucleus which keep them from reproducing the life span of a RBC is 120 days , they are biconcave with raised edges and a flattened middle to allow greater surface area for more efficient diffusion of oxygen and movement ease through time capillaries . They are occupied by pigment call hemoglobin giving it its red color, hemoglobin an iron –based protein combines temporarily with oxygen and carbon dioxide so that gases can be transported and then released, and hemoglobin carries oxygen or carbon dioxide but not both at any given time. Special proteins on the surface of RBC determine the different blood type.
Leukocytes – white blood cells serve as part of the body’s immune system by protecting the body from invading pathogens and by removing dead cells and substances. WBC combat irritants by producing histamine, in extreme cases causes dilation of capillaries, decreased blood pressure and constriction of smooth muscles of the bronchi. Other WBC produce antibodies, which are produced in response to specific foreign substances such as bacteria, viruses or cells of an incompatible blood type.
Thrombocytes – also known as platelets, they are fragmented cells that are important in blood clotting or coagulation, their jagged shape helps the adhere to torn surfaces easily, such as occurs in a damaged blood vessel. The life span is 10 days. The clotting process starts when a vessel is damaged and it takes only a few minutes to form a clot. Coagulation is the process of transforming fibrinogen in plasma into fibrin threads and trap red blood cells Vitamin K and calcium are also need during this process. Once a clot is formed it goes through a process of tightening that draws the injured are of vessel wall closer together for repair, then reduces and stops blood loss. At the time a clot is formed an enzyme is formed which has the ability to slowly dissolve the clot over time when healing is complete.
Plasma – Straw colored liquid that helps transport blood cells. Approximately 55% of blood is plasma. Plasma itself is 90% water 10% solutes such as sodium, potassium and fibrinogen which aids in blood clotting.
Blood Types – The most common blood typing system is ABO system
Type a Presence of antigen a, antibodies B
Type B - b antigen, Antibodies A
Type AB a & B antigens no antibodies
Type O – absence of both antigens presence