Ch4: The Heart

cardiovascular system characteristics:

-consists of heart and blood vessels

-heart: hollow, cone shaped muscular pump, pumps 2 different types of blood, the pump (force)

-blood vessels: 3 different types, transports blood throughout the body

away

arteries transport blood ____ from the heart

towards

veins transport blood ______ the heart

capillaries

-transport blood between arteries and veins

-perform nutrient, gas, and waste exchange

pulmonary circuit

-carries deoxygenated blood from heart to the lungs

-then drops off CO2 and picks up O2

-then flows back to the heart

-think respiratory and heart —> lungs —> heart

-DO2 blood!

systemic circuit

-transports oxygenated blood and nutrients to body cells

-removes waste from cells

-flows back to heart

-think heart —> all body systems

-O2 blood!

closed circuits

both the pulmonary & systemic circuits are examples of ___________, which means that the two types of blood will never and shouldn’t ever mix

the lungs

where is blood oxygenated?

pulmonary; systemic

right side of the heart pumps to the ________ circuit, and the left side of the heart pumps to the _______ circuit

heart structure characteristics:

-size of a fist

-located inside thoracic cavity behind the sternum

-divided into left & right hemispheres

-tilts to the left at the apex

-considered a double pump

pericardium (pericardial sac)

-covering over heart and proximal ends of large blood vessels

-protects the heart

-has 4 layers: fibrous, parietal, visceral, & pericardial cavity

fibrous pericardium

-tough outer layer

-surrounds double-layered serous membrane

parietal pericardium

-deep to fibrous pericardium

-outer layer of serous membrane

visceral pericardium

-inner layer of serous membrane

-attached to surface of the heart

-also called epicardium

pericardial cavity

-space between visceral and parietal layers of serous pericardium

walls of the heart

1. epicardium: outer, thin layer; also called visceral pericardium; reduces friction

2. myocardium: middle layer; thickest layer; composed of cardiac muscle tissue

3. endocardium: inner, thin layer; forms inner lining of all heart chambers