Chapter 37 Circulatory and Respiratory Systems 37-1 The Circulatory System Objectives: Name the three types of blood vessels in the circulatory system. Describe blood pressure.

Blood Vessels The circulatory system is known as a closed system because the blood is contained within either the heart or the blood vessels at all times. This system contains two subsystems: the pulmonary circulation (lungs) and the systemic circulation.

Blood Vessels Arteries Capillaries and Veins The large, muscular vessels that carry blood away from the heart and to the body Arteries are made up of three layers: an inner endothelial layer, a middle layer of smooth muscle, and an outer layer of connective tissue. Capillaries and Veins The capillaries are a vast network of tiny vessels that allow an exchange between the blood and the cells to occur. A vein is a bundle of vascular tissue that transports fluids and waste back to the heart.

Blood Vessels In order to measure blood pressure, Systolic pressure, measured first, is the pressure of the blood when the ventricles contract. Diastolic pressure, measured second, indicates the steady flow of blood through the artery Normal blood pressure Males 120/80 Females 110/70

Chapter 37 Circulatory and Respiratory Systems 37-2 Blood Objectives: Describe blood plasma. Explain the functions of red blood cells, white blood cells, and platelets.

Blood Blood is composed of a liquid medium—plasma—and blood solids–red and white blood cells and platelets. Plasma (60% of make-up) Plasma is a sticky, straw-colored fluid that is about 90 percent water and includes metabolites, nutrients, wastes, salts, and proteins. Plasma provides cells with nourishment and carries various proteins.

Blood Red Blood Cells (part of 40%) A red blood cell is a disc-shaped cell that has no nucleus and transports oxygen to cells in all parts of the body. Immature red blood cells synthesize large amounts of an iron-containing protein called hemoglobin. Hemoglobin is the molecule that transports oxygen.

Blood White Blood Cells (part of 40%) Platelets (part of 40%) White blood cells are cells in the blood that destroy bacteria, viruses, and toxic proteins and helps the body develop immunities. Platelets (part of 40%) Platelets are partial cells that are necessary for the formation of a blood clot.

Blood Blood Types Red blood cells have surface proteins that are used to classify a person’s blood. The type of surface protein determines a person’s blood type.

Blood Blood Types A-B-O System Surface markers can be A or B, both (AB) or neither (O) Rh System based on the presence or absence of the Rh antigen. A person with Rh antigens is Rh positive; a person without Rh antigens is Rh negative If blood of a different type is introduced into the body it will be treated as a foreign invader

37-1/37-2 Classwork Compare the functions of the three types of blood vessels in the circulatory system. List the main function of red blood cells, white blood cells, and platelets.