A&P Lab 2- Exercise 30 Anatomy of the Heart
electrocardiogram
An ECG stands for?
right atrium
Blood from the systemic circulation enters what chamber of the heart?
Bradycardia referes to a heart rate under 60 beats/min
Bradycardia referes to a heart rate under __________ beats/min
The mitral valve has only two flaplike cusps while the tricuspid valve has three.
Compare and contrast the structure of the mitral and tricuspid valves.
Blood vessels carry blood to and from the lungs for gas exchange. (oxygen poor blood) right
Describe the role of the pulmonary circuit.
Left side of the heart where blood vessels carry oxygenated blood from lungs to all body tissues.
Describe the role of the systemic circuit.
Describe the unique anatomical features of cardiac muscle. intercalated discs What role does the unique structure of cardiac muscle play in its function? allows electrical connection between the cells which is vital to the function of the heart as a whole
Describe the unique anatomical features of cardiac muscle. What role does the unique structure of cardiac muscle play in its function?
right coronary artery (RCA)
Description: Branches from the ascending aorta just above the aortic valve and encircles the heart in the coronary sulcus Areas supplied/branches: Its branches include the right marginal artery and the posterior interventricular artery
anterior interventricular artery
Description: branches off the LCA and is located in the anterior interventricular sulcus. This artery is referred to clinically as the left anterior descending artery (LAD) Areas supplied/branches: supplies the anterior portion of the interventricular septum and the anterior walls of both ventricles
posterior interventricular artery
Description: branches off the RCA and is located in the posterior interventricular sulcus Areas supplied/branches: supplies the posterior walls of the ventricles and the posterior portion of the interventricular septum. Near the apex of the heart, it merges (anatamoses) with the anterior ventricular artery.
great cardiac vein
Description: located in the anterior interventricular sulcus; parallel to the anterior interventricular artery Areas drained: anterior portions of the right and left ventricles
coronary sinus
Description: located in the coronary sulcus on the posterior surface of the heart; drains into the right atrium Areas drained: The entire heart; the great, middle, and small cardiac veins all drain into here
anterior cardiac veins
Description: located on the anterior surface of the right atrium Areas drained: they drain directly into the right atrium
small cardiac vein
Description: located on the lateral right ventricle, parallel to the right marginal artery Areas drained: lateral right ventricle
left coronary artery (LCA)
Description: branches from the ascending aorta and passes posterior to the pulmonary trunk Areas supplied/branches: it branches include the anterior interventricular artery and the circumflex artery
circumflex artery
Description: branches off the LCA: located in the coronary sulcus Areas supplied/branches: supplies the left atrium and the posterior portion of the left ventricle
right marginal artery
Description: branches off the RCA and is located in the lateral portion of the right ventricle Areas supplied/branches: supplies the lateral right side of the heart
middle cardiac vein
Description: located in the posterior interventricular sulcus, parallel to the posterior interventricular artery Areas drained: posterior portions of the right and left ventricles
The left ventricle was bigger than the right ventricle.
During the sheep heart dissection, you were asked initially to identify the right and left ventricles without cutting into the heart. During this procedure, what differences did you observe between the two chambers?
Cardiac muscle have branching cells and intercalated discs which skeletal muscles lack.
How would you distinguish the structure of cardiac muscle from that of skeletal muscle?
A: mitral valve
Identify the following parts of the heart. A:
B: subendocardial conduction network
Identify the following parts of the heart. B:
C: chordae tendineae
Identify the following parts of the heart. C:
D: interventricular septum
Identify the following parts of the heart. D:
A: P wave
Identify the parts of an ECG. A:
B: QRS complex
Identify the parts of an ECG. B:
C: T wave
Identify the parts of an ECG. C:
D: Q-T interval
Identify the parts of an ECG. D:
superior vena cava, inferior vena cava, & coronary sinus
Name the three vessels that deliver oxygen-poor blood to the right atrium.
tricuspid valve
Name the valve that has three flap like cusps anchored to the papillary muscle by chordae tendineae.
interventricular septum
Name the wall of the heart that separates the two ventricles.
Semilunar valves prevent backflow into the ventricles; mitral and tricuspid valves prevent backflow into the atriums. Using your own observations, explain how the operation of the semilunar valves differs from that of the atrioventricular valves. AV valves push blood into the great vessels while SL valves prevent back flow of blood from the great vessels into the ventricles.
Semilunar valves prevent backflow into the ___________________________; mitral and tricuspid valves prevent backflow into the ________________________________. Using your own observations, explain how the operation of the semilunar valves differs from that of the atrioventricular valves.
Tachycardia referes to a heart rate over 100 beats/min
Tachycardia referes to a heart rate over __________ beats/min
The external surface of the heart is known as the visceral (or epicardium) pericardium. The walls of the heart consists of several layers. myocardium is the thickest layer and composed mainly of cardiac muscle and reinforced by a cardiac skeleton.
The external surface of the heart is known as the _________ pericardium. The walls of the heart consists of several layers. _________ is the thickest layer and composed mainly of cardiac muscle and reinforced by a cardiac skeleton.
The heart is enclosed within a double-walled sac called the pericardium. The loose-fitting superficial part of the sac is the fibrous pericardium. The parietal pericardium lines the internal surface of the fibrous pericardium.
The heart is enclosed within a double-walled sac called the pericardium. The loose-fitting superficial part of the sac is the __________ pericardium. The __________ pericardium lines the internal surface of the fibrous pericardium.
cardiac skeleton
The myocardium is reinforced with dense fibrous connective tissue, the ________ which is thicker around the heart valves and at the base of the great vessels leaving the heart.
fibrous pericardium, parietal layer, and visceral layer of epicardium
What are the three coverings of the heart from superficial to deep?
interatrial septum and interventriucular septum
What internal partition or septum divides the heart longitudinally separating the atria? What septum divides the ventricles?
Connects heart where gap junctions occur so that electrical impulses can be moved throughout the heart.
What is the function of intercalated discs in cardiac muscle?
Reduce friction during heart activity.
What is the function of the fluid that fills the pericardial sac?
coronary circulation
What is the functional blood supply of the heart? (also the shortest circulation in the body)
transportation (oxygen, nutrients, cell wastes, electrolytes, and many other substances vital to the body's homeostasis to and from the body cells)
What is the major function of the cardiovascular system
to prevent the back flow of blood fro the ventricles into the atria (AV valves) and prevent back flow of blood from the great vessels into the ventricles (SL valves)
What is the purpose of the valves, more specifically the cusps?
When you measured thickness of ventricular walls, was the right or left ventricle thicker? left Knowing that structure and function are related, how would you say this structural difference reflects the relative functions of these two heart chambers? The left ventricle is bigger and walls are thicker in order to pump oxygenated blood throughout the whole body.
When you measured thickness of ventricular walls, was the right or left ventricle thicker? Knowing that structure and function are related, how would you say this structural difference reflects the relative functions of these two heart chambers?
Atrioventricular valves: 1) tricuspid valve 2) mitral valve
Which valves are anchored by chordae tendineae?
Semilunar valves: 1) pulmonary valve 2) aortic valve
Which valves close when the cusps fill with blood?
circumflex artery, DIRECTLY supplies blood to the posterior portion of the left ventricle.
__________, DIRECTLY supplies blood to the posterior portion of the left ventricle.
Posterior interventricular artery, a branch of the right coronary artery, directly supplies blood to the posterior portion of the inter ventricular septum.
__________, a branch of the right coronary artery, directly supplies blood to the posterior portion of the interventricular septum.
ventricles
discharging chambers of the heart
coronary sinus
drains blood into the right atrium
great cardiac vein
drains the anterior portion of the right and left ventricles
aurticles
earlike flaps of tissue projecting from the atria
small cardiac vein
immediately drains the lateral right ventricle
myocardium
layer composed of cardiac muscle
mitral or bicuspid valve
left AV valve
endocardium
lining of the heart chambers
mediastinum
location of the heart in the thorax
coronary arteries
provide nutrient blood to the heart muscle
semilunar valves
pulmonary and aortic valves
atria
receiving chambers of the heart
tricuspid valve
the right AV valve
atrioventricular valves
tricuspid and mitral valves
semilunar (SL) valves
valves located between a ventricle and a great vessel
atrioventricular (AV) valves
valves located between the atrium and ventricle on the left and right side of the heart
epicardium
visceral pericardium
