Name ______________________________The Heart: Notes
Function of the Circulatory System• Transportation system by which
______________________________________________________, and ____________________________________________________________________________.
• Also carries substances called ______________________, which control body processes, and ___________________________ to fight invading germs.
Three major parts– The ____________________ – The ____________________ – The _____________________________
Circulation• Two parts • Heart acts as _________________________________
– Blood from the _________________________ pump is _______________________ and ________________________________ (oxygen-poor)• Travels through ____________________________________________ where
it gets fresh oxygen and becomes ___________________________– Blood ___________________________ through
__________________________________ back to the heart's left side pump• Pumped out into the ________________
Three Kinds of Circulation:• Pulmonary circulation
– Movement of blood __________________________________________________________
• Coronary circulation– Movement of blood
__________________________________________________________ • Systemic circulation
– _________________________________________________________________ , except for the heart and lungs
The Heart’s Role in Blood Circulation• Systemic circulation
– Blood flows from the ______________ of the heart through the ___________ tissues and back to the ________________ of the heart
• Pulmonary circulation– Blood flows from the __________________ of the heart to the
_______________ and back to the ______________________ of the heart
Cardiac Circulation• Blood in the heart chambers does not nourish the myocardium• The heart has its own nourishing circulatory system consisting of
– ______________________________—branch from the aorta to supply the heart muscle with oxygenated blood
– ______________________________—drain the myocardium of blood– ______________________________—a large vein on the posterior of the heart,
receives blood from cardiac veins• Blood empties into the right atrium via the coronary sinus
The Heart• Location
• Thorax between the lungs in the inferior _____________________• Orientation
• Pointed apex directed toward left hip• Base points toward right shoulder
• About the ____________________________
Coverings• _____________________________—a double-walled sac
– Fibrous pericardium is loose and superficial– Serous membrane is deep to the fibrous pericardium and composed of
two layers
• _____________________________– Next to heart; also known as the epicardium
• _____________________________– Outside layer that lines the inner surface
of the fibrous pericardium– Serous fluid fills the space between the layers of pericardium
Wall• Three layers
– ________________________• Outside layer• This layer is the visceral pericardium• Connective tissue layer
– ________________________• Middle layer• Mostly cardiac muscle
– ________________________• Inner layer• Endothelium
Chambers• Right and left side act as separate pumps• Four chambers
– ______________• Receiving (_______) chambers
– Right atrium– Left atrium
– _________________• Discharging (_________) chambers
– Right ventricle– Left ventricle
Septum• _____________________ septum
– Separates the two ventricles• _____________________ septum
– Separates the two atria
Valves• Allow blood to flow in only one direction to prevent backflow• _____________ valves
– Atrioventricular (AV) valves—between atria and ventricles• _______________ (mitral) valve (_______ side of heart)• _______________ valve (__________ side of heart)
– Semilunar valves—between ventricle and artery• ___________________ semilunar valve• ___________________ semilunar valve
• AV valves – Anchored in place by ____________________________ (“heart strings”)
– __________________________________________ and closed during ventricular contraction
• Semilunar valves– __________________________________________ but open during ventricular
contraction• Notice these valves operate opposite of one another to force a one-way path of
blood through the heart
Heart Sounds• Heart sounds are _____________________________ as they open and close• Valves _______________________________ from one chamber to another• Prevent ____________________
Associated Great Vessels• Arteries
– _______________• Leaves left ventricle
– _____________________________• Leave right ventricle
• Veins– ____________________________________
• Enter right atrium– _______________________________ (four)
• Enter left atrium
Blood Flow Through the Heart• ______________________________________________________ dump blood into the
right atrium• From _______________________, through the _______________________, blood
travels to the right ventricle• From the ________________________, blood leaves the heart as it passes through
the ___________ _________________________________ into the pulmonary trunk• _________________________ splits into right and left
____________________________________ that carry blood to the lungs• Oxygen is picked up and carbon dioxide is dropped off by blood in the
__________________• Oxygen-rich blood returns to the heart through the four
________________________________• Blood enters the ______________________ and travels through the
__________________________ into the left ventricle• From the _______________________, blood leaves the heart via the
_________________________ valve and ___________________
How does the heart work?
Heart Beats (Lub Dub)• _______________________________________
– Group of cells on the ______________________________________ near the entrance of the superior vena cava
– “___________________” of the heart• _______________________________________
– Electrically ________________________________________________– Signals go from the ____________________ through the
____________________________ allowing the ventricles to contract