The Cardiovascular System Blood The Heart Blood Vessels

Cardiovascular system Functions: Transports: oxygen carbon dioxide nutrients wastes chemical messengers Homeostasis of pH temperature clotting Disease Defense

Systemic Vessels

Blood = Plasma + Formed (Cellular) Elements ~ 55% blood volume ~ 92% of plasma is water High dissolved oxygen content Dissolved proteins Albumins Globulins Fibrinogen Cells ~ 45% blood volume RBCs ~ 99% of cells WBCs ~1% of cells

The Proteins in Plasma Albumins 60% of plasma proteins viscosity Globulins 35% of plasma proteins Immunoglobulins attack foreign invaders Fibrinogen React in clotting reaction Form fibrin (serum = plasma - fibrinogen)

Cellular Components RBCs (erythrocytes)~ 99% of all cells. ~ 1/2 blood volume. Hematocrit = % of blood occupied by cellular components (~ RBC volume) Lacks mitochondria, ribosomes, nuclei Life span = ~120 days

Scanning Electron Micrograph (SEM) of Erythrocytes or Red Blood Cells (RBCs) on the tip of a hypodermic needle.

Hemoglobin

Erythropoietin

Life and death of an RBC

Anemia Pernicious anemia Hemorrhagic anemia Sickle cell anemia Low Fe absorption – Vitamin B12 and instrinsic factor Hemorrhagic anemia Sickle cell anemia Hypochromic anemia Hemolytic anemia polycythemia

Pernicious anemia

Blood Types - ABO

What type?

What type?

Erythroblastosis fetalis

Granular Leukocytes (WBCs) Neutrophils 70% circulating leukocytes Highly active aggressive phagocytes Eosinophils (acidophils) Much less common Attracted to foreign compounds reacted with antibodies Parasitic infections Basophils Relatively rare allergeries Release histamines.

Agranular Leukocytes Lymphocytes Primary cell of the lymphatic system T-cells attack foreign cells directly B-cells produce antibodies Monocytes Migrate into peripheral tissues and differential into Macrophages Highly mobile phagocytic cells diapedesis

Never Let Monkeys Eat Bananas Platelet cells (Thrombocytes) Fragments of Megakaryocytes enclosed packets of cytoplasm for blood clotting Never Let Monkeys Eat Bananas

Pulmonary circuit Systemic circuit - from heart to lungs back to heart to body back to heart

Arteries = vessels that carry blood away from the heart. Veins = vessels that return blood to the heart. Capillaries = smallest vessels, found between smallest arteries and veins. These are the exchange vessels.

The Heart Myocardium Chambers Valves (one-way-flow) Pericardial Sac

Location of the Heart in the Thoracic Cavity

Epicardium Visceral pericardium Myocardium Muscular wall of the heart Endocardium Epithelium of inner surface

The Heart is Dual Pump Most of the heart is Myocardium - Contractile Myocardiocytes * Interconnected by intercalated discs

Position and Orientation of the Heart

Sectional Anatomy of the Heart

Blood Flow through Heart RA -> ______ valve -> RV -> _____ valve -> pulmonary trunk -> pulmonary ______s -> lungs -> pulmonary _____s -> LA -> ____ valve -> LV -> ___ valve -> ascending aorta -> aortic arch Receives blood from systemic circuit Superior vena cava Inferior vena cava Coronary veins Return blood to coronary sinus then on to right ventricle Foramen ovale open during embryonic development Fossa ovalis after birth

Right Ventricle Right AV valve / Tricuspid valve Blood comes from right atrium to right ventricle through the atroventricular (AV) valve Right AV valve / Tricuspid valve Three cusps of fibrous tissue - Chordae tendineae - Papillary muscles - Pulmonary semilunar valve Blood leaves Rt Ventricle via pulmonary Semilunar valve to pulmonary trunk. Branches to left and right pulmonary arteries

How do papillary muscles work? Valves of the Heart How do papillary muscles work?

Heart Valves and Heart Sounds Closure of the AV valves create the 1st heart sound (‘lub’). Closure of the semilunar valves create the 2nd heart sound (‘dupp’). Placement of a stethoscope varies depending on which heart sounds and valves are of interest.

Coronary Circulation

Normal Functional Heart Anatomy

Congenital Heart Defects

Congenital Heart Defects

Congenital Heart Defects

The Cardiac Cycle

The Electrocardiogram Recording of the electrical activities in the heart P wave = Atrial Depolarization QRS complex = Ventricular Depolarization T wave = Ventricular Repolarization

ECG

The Conducting System of the Heart

Heart cycle