Download Circulatory System Chapters 17, 18, 19

Circulatory System Chapters 17, 18, 19

• Plasma consists of : – 92% water, 8% solutes - mostly proteins (albumin, globulins (antibodies), fibrinogen), hormones, gasses (CO2, O2), nutrients (glucose), wastes (urea, ammonia).

• Serum is fluid left after plasma clotting proteins are removed.

• 45% Formed (cellular) elements. – all formed in the red marrow, short lived in circulation. • Consists of: – < 1% buffy coat (wbc and platelets) between plasma and rbcs. – Leukocytes - White Blood Cells - primarily function to defend against foreign bodies (bacteria, viruses, foreign proteins, etc). – Platelets (Thrombocytes) - cytoplasmic fragments. Help stop blood flow by forming a platelet plug.

• 45% RBC (hematocrit- estimate of rbc mass). • Erythrocytes - Red Blood Cells 99%+ of formed elements of blood.

Time to Draw!

Lungs Pulmonary circuit

Systemic circuit Body Tissues oxygen poor oxygen rich

Lungs Pulmonary circuit

Systemic circuit Body Tissues oxygen poor oxygen rich

Lungs

Right atrium

Left atrium

Right ventricle

Left ventricle

Pulmonary circuit

Systemic circuit

Body Tissues

oxygen poor oxygen rich

Pulmonary vein Lungs

From RV

Right atrium

Left atrium

Superior Vena Cava Inferior Vena Cava Atrioventricular valve - tricuspid

Right ventricle

Left ventricle

To lungs

Atrioventricular valve – bicuspid or mitral

Aortic semilunar valve

Aorta To body Pulmonary artery Pulmonary semilunar valve Body Tissues

oxygen poor oxygen rich

myocardium endocardium = endothelium Epicardium = visceral pericardium

Interventricular septum

CHORDAE TENDONAE - Tendon-like cords connect pointed ends and undersurfaces of AV flaps to papillary muscles attached to inner surface of ventricle. PAPILLARY MUSCLES - Contract as ventricles contract. Keeps AV flaps from everting back into atria, and stops backflow into atria.

The Pacemaker and Conduction System of the Heart Intra-atrial path Sinoatrial node

Right atrium

Left atrium

Atrioventricular bundle (of His) Atrioventricular node

Right ventricle

Left ventricle

Left and Right bundle branches Conduction myofibers (purkinje)

CORONARY ARTERIES - arise from small openings (aortic sinus) just above aortic semilunar valve. Arteries form an upside down crown around about the heart.

CORONARY VEINS - Generally travel with arteries. Drain into right atrium by way of coronary sinus. CORONARY SINUS- When cardiac veins join together on posterior side of heart they form a sinus which drains into the right atrium.