Heart Anatomy Flashcards
Describe the location of the heart in the thoracic cavity and what the cardiac notch is.
Located in a space called the mediastinum. The cardiac notch is a depression on the left lung in order to make room for the heart.
Explain the systemic circuit by following a drop of blood beginning in the left ventricle. Name the chambers and blood vessels it will encounter on its journey away from the heart and back. When is this blood oxygen-rich? When is it oxygen-poor?
This chamber sends oxygenated blood out to the body.
The left ventricle contracts, pumping oxygenated blood into the aorta, which quickly splits to send blood to the arms and head. The aorta then makes a U-turn and descends back down behind the heart to deliver blood to the rest of the body. Upon arrival at destination blood trickles into systemic capillaries where gas exchange occurs. Oxygen and nutrients exit the systemic capillaries to be used by cells in their metabolic processes, and carbon dioxide and waste products will enter the blood. Veins will carry the blood back to the heart eventually flowing into the superior vena cava, which drains blood from the head and arms, and the vena cava, which drains blood from the rest of the body. The blood then flows into the right atrium, which pumps blood into the right ventricle.
Explain the pulmonary circuit by following a drop of blood beginning in the right ventricle. Name the chambers and blood vessels it will encounter on its journey away from and back to the heart. When is this blood oxygen-rich? When is it oxygen-poor?
This chamber sends deoxygenated blood to the lungs.
The right ventricle contracts and pumps the deoxygenated blood into the pulmonary trunk, A large artery that will quickly split into the left and right pulmonary arteries, which eventually turns into pulmonary capillaries. this is where gas exchange occurs: Carbon dioxide exits the blood (exhaled) and oxygen enters to be distributes throughout the body (inhaled). Now the oxygenated blood will return through the pulmonary capillaries in the lungs, return to the pulmonary veins, which carries blood into the left atrium of the heart. When the left atrium contracts it pumps blood into the left ventricle.
What are the layers of the pericardium? Which are tough layer(s) to protect the heart and hold it in place? Which are slippery layers to reduce friction during heartbeats?
The fibrous pericardium and the serous pericardium. The fibrous pericardium is made up of tough dense connective tissue that protects the heart and maintains its position in the thorax. The more delicate serous pericardium consists of two layers: the parietal pericardium, which is fused to the fibrous pericardium. And the inner visceral pericardium which is fused to the heart and part of the hearts wall. The pericardium cavity, filled with lubricating serous fluid, lies between the layers of the pericardium.
What are the functions of the coronary arteries and veins? What does this have to do with coronary artery disease?
The coronary arteries deliver oxygen rich blood to the myocardium to nourish the cardiac muscle cells. The cardiac veins are now responsible for returning the now deoxygenated blood back to the right atrium. The coronary arteries on the surface of the heart are commonly affected by atherosclerosis, which causes a condition called ischemia. Ischemia causes cells to receive insufficient amounts of oxygen called hypoxia. If left untreated this can cause angina or a heart attack.
Name the three layers of the heart wall and in a few words summarize their functions.
Epicardium- The outermost layer of the heart wall. It is a thin layer fused to the heart and with the parietal pericardium. It created the pericardial space where serous fluid is found.
Myocardium- The middle and thickest layer. It is the contraction of the myocardium that pumps blood through the heart and into the major arteries. They form a figure 8 around atria and base of great vessels, this allows the heart to pump blood more efficiently than a linear pattern would.
Endocardium- The innermost layer of the heart wall. The endocardium lines the chambers where the blood circulates and covers the heart valves. It is made of simple squamous epithelium and provides a slippery-smooth surface for blood cells as they rush through the heart.
Can you name all of the heart valves? Where are they found? Which have chordae tendineae and papillary muscles attached to them and why?
AV valves:
Tricuspid valve- Between the right atrium and right ventricle. This valve keeps blood rom returning to the right atrium after it has already moved into the right ventricle.
Bicuspid valve (mitral valve)- Between the left atrium and ventricle. Prevents blood from returning to atrium after moving to the ventricle.
The papillary muscles and chordae tendineae are attached to BOTH of the AV valves. To prevent any potential backflow, the papillary muscles also contract, generating tension on the chordae tendineae. This prevents the flaps of the valves from being forced into the atria and regurgitation of the blood back into the atria during ventricular contraction.
Semilunar valves:
Pulmonary semilunar valve- The base of the pulmonary trunk. Prevents backflow of blood into the pulmonary trunk.
Aortic semilunar valve- Prevents blood from returning to the atrium after moving to the ventricle.
When blood is returning from the lungs and entering the right atrium of the heart, this is considered part of the _____ circuit.
Pulmonary
The primary pumping chambers of the heart are the _____ and _____.
Left and right ventricle.
What term means “muscle”?
Myo-
What vessel carries oxygen rich blood?
Aorta
Arteries carry blood….
Away from the heart
Veins carry blood
Into/Towards the heart
