The Circulatory System

Vertebrates have Closed circulatory systems A system that uses a continuous series of vessels of different sizes to deliver blood to body cells and return it to the heart The human closed circulatory system is sometimes called the cardiovascular system. What is an open circulatory system?

Multicellular animals do not have most of their cells in contact with the external environment and so have developed circulatory systems to transport nutrients, oxygen, carbon dioxide and metabolic wastes. Vertebrates have Closed circulatory systems

Components of the circulatory system: 1.blood: 2.heart: 3.blood vessels:

1.Blood Human Blood Cells

The Components of Blood Plasma –liquid component of blood accounts for about ____ of total blood volume. Plasma consists of ____water and ____ dissolved materials that include: –acts as a buffer, maintaining pH near 7.4.

Red blood cells (erythrocytes) are flattened, doubly concave cells and lack a nucleus carry oxygen ___________________ small (7 µm in diameter): _________________ _____ million hemoglobin molecules per cell. Humans have a total of ________ (about 1/3 of all the cells in the body) The Components of Blood

Red blood cells are continuously manufactured in _________________________________________ ________________ Life-span of an erythrocyte is only ________, after which they are destroyed in ______ and __________. –Iron from hemoglobin is recovered and reused by red marrow. The liver degrades the heme units and secretes them as pigment in the bile, responsible for the colour of feces. Each second 2 million red blood cells are produced to replace those taken out of circulation. The Components of Blood Red blood cells cont.

The Components of Blood White blood cells, (_________) larger than rbc’s but occupy less than ____ of the blood volume, have a _________, but lack __________. They function in the _______ ________ response. made from _________ in _________.

The Components of Blood White blood cells, (leukocytes) There are Five types of leukocytes 1. ___________: enter the tissue fluid by squeezing through capillary walls and ___________ foreign substances. 2. ___________: release white blood cell growth factors, causing a population increase for white blood cells.

The Components of Blood White blood cells, (leukocytes) 3. ____________: fight infection. 4. __________: attack cells containing _______. 5. __________: produce __________. Antigen- antibody complexes are phagocytized by a macrophage

Platelets carry chemicals essential to blood clotting. Platelets survive for _______ before being removed by the liver and spleen. There are ________ to ________ platelets in each ________ of blood. Platelets stick and adhere to tears in blood vessels; they also release ________ _________. A hemophiliac's blood cannot clot. The Components of Blood Platelets

Red Blood Cells, Platelets and T-lymphocyte (erythocytes = red; platelets = yellow; T-lymphocyte = light green)