Lecture Outline - Chapter 5

5.1 Red Blood Cells (p. 109)
	1.	Red blood cells (erythrocytes) are biconcave and anucleate. These are 4 to 6 million red blood cells per mm3 in whole blood.
	2.	Hemoglobin (p. 109, Fig. 5.3)
		a.	Hemoglobin is the respiratory pigment that transports oxygen.
		b.	Each hemoglobin molecule has four polypeptides that comprise the protein globin 	and an iron-containing, oxygen-carrying heme portion.
		c.	Hemoglobin also assists in the transport of carbon dioxide.
	3.	Life Cycle of Red Blood Cells (p. 111, Figs. 5.4, 5.5)
		a.	Red blood cells (RBCs) are produced in the red bone marrow of all bones in infants; in adults, RBCs are made only in certain bones.
		b.	Reduced oxygen triggers RBC production involving the hormone erythropoietin.
		c.	All blood cell types form from stem cells.
		d.	Myeloid stem cells produce erythroblasts, which mature to become RBCs. 
		e.	RBCs live for about 120 days; then, phagocyctic cells in the liver and spleen destroy them.
		f.	Anemia (p. 111)
			Anemia results from too few red blood cells and/or insufficient hemoglobin. Types of anemia include iron-deficiency anemia, pernicious anemia, and sickle-cell disease. 
			ECOLOGY FOCUS: Carbon Monoxide, a Deadly Poison (p. 112, Fig. 5A)
			i.	Carbon monoxide is produced through the incomplete combustion of gasoline and natural gas.
			ii.	Carbon monoxide is deadly because it binds 200 times more tightly to hemoglobin than does oxygen. 
			iii.	A number of measures are available to lessen carbon monoxide production. 
5.2 White Blood Cells (p. 113, Fig. 5.6)
	1.	White blood cells (leukocytes) are large, white, and nucleate, and function in immunity. They squeeze through capillaries and invade tissues when needed.
	2.	Types of White Blood Cells (p. 113)
		a.	Granular leukocytes have visible granules in their cytoplasm. Neutrophils engulf bacteria and debris through phagocytosis. Eosinophils are numerous during allergic reactions or parasitic infections. Basophils become mast cells in tissues, releasing histamine.
		b.	Agranular leukocytes include monocytes, which become macrophages that phagocytize pathogens and cellular debris in tissues, and lymphocytes (B lymphocytes and T lymphocytes) responsible for immunity.
		c.	Leukemia, a type of cancer, is characterized by an abnormally large number of immature leukocytes that crowd red bone marrow.
5.3 Blood Clotting (p. 114, Fig. 5.7)
	1.	Platelets (thrombocytes) form as megakaryocytes fragment. Platelets are involved in blood clotting.
	2.	Blood Clotting Has Steps (p. 114)
		a.	When tissues are damaged, platelets stick to the damaged area, partially sealing torn blood vessels.
		b.	Injured tissues release prothrombin activator, which converts prothrombin to thrombin. This step requires calcium ions.
		c.	Thrombin functions as an enzyme to convert fibrinogen into fibrin.
			HEALTH FOCUS: What to Know When Giving Blood (p. 115)
			i.	Do not give blood if you have AIDS or any of its symptoms, have taken illegal drugs by needle, or have other risk factors associated with HIV.
			ii.	The donor cannot become infected with HIV or other diseases while donating blood. 
5.4 Plasma (p. 116, Table 5.2)
	1.	Plasma is the liquid portion of blood, made up mostly of water, but also containing salts, small organic molecules, hormones, and plasma proteins.
	2.	Plasma Proteins (p. 116)
		a.	The liver makes most plasma proteins, which constitute 7% of plasma. They help to buffer the blood, transport molecules, and maintain osmotic pressure.
		b.	Albumin transports bilirubin.
		c.	Globulin is a component of lipoproteins, which transport cholesterol.
		d.	Gamma globulins are the antibodies of immunity.
		e.	Fibrinogen is involved in blood clotting.
5.5 Exchange of Materials with Tissue Fluid (p. 116, Fig. 5.8)
	1.	Arterial End of the Capillary (p. 116)
		a.	Arterial blood leading to capillaries contains nutrients and oxygen.
		b.	High pressure in arterial blood forces fluid through the capillary walls into tissues. 
	2.	Midsection (p. 116)
		Diffusion is responsible for the movement of gases, nutrients, and wastes between the tissues and the blood.
	3.	Venous End of the Capillary (p. 117, Fig. 5.9)
		a.	Blood pressure is reduced, but osmotic pressure remains stable, pulling water from tissues back into the capillaries.
		b.	Lymphatic capillaries drain excess tissue fluid.
5.6 Blood Typing (p. 118)
	1.	Antigens are foreign substances that trigger the formation of antibodies in the immune response. The membrane of RBCs contains antigens.
	2.	ABO System (p. 118, Fig. 5.10, Table 5.3)
		a.	The most common system for typing blood is the ABO system. Blood types A, B, and AB correspond with having specific antigens on the surface of RBCs; type O is an absence of these antigens.
		b.	All persons have antibodies in their plasma for the ABO antigen not carried on their own RBCs.
	3.	Rh System (p. 119, Fig. 5.11)
		a.	The Rh system represents another antigen on the surface of RBCs. Rh positive (Rh+) indicates presence of the antigen; Rh negative (Rh-) indicates its absence.
		b.	Rh factor is especially important in Rh_ mothers who carry Rh+ fetuses because of the possibility of hemolytic disease of the newborn.