What is the fibrous pericardium?; The outer layer of the pericardium, which is a tough layer protecting the heart.
What are the three layers of the heart wall?; The three layers of the heart wall are the pericardium, myocardium, and endocardium.
What is the myocardium?; The myocardium is the muscular middle layer of the heart wall.
What is the endocardium?; The endocardium is the very smooth inner layer that lines the chambers and heart valves.
Where is the heart situated in the body?; The heart is situated in the thoracic cavity between the 2 lungs, in a space called the mediastinum.
What is the size of the heart in adults?; The heart is about the size of an adult's fist, weighing between 250-350 grams.
What is the direction of the pointed apex of the heart?; The pointed apex of the heart is directed towards the left hip.
What is the direction of the broad, flat base of the heart?; The broad, flat base of the heart points towards the right shoulder.
What is the function of the endocardium?; The endocardium lines the chambers and heart valves, providing a very smooth surface for blood flow.
What is the pericardium?; The pericardium is a double-walled sac that encloses the heart.
What is the purpose of the fibrous pericardium?; It is a tough layer that protects, anchors, and prevents overfilling of the heart.
What is the serous pericardium?; It is a double-layered sac that surrounds the heart, consisting of the parietal layer and the visceral layer.
What is the pericardial cavity?; It is the space between the parietal and visceral layers of the serous pericardium, containing a serous fluid film that reduces friction during contraction and relaxation.
What is the myocardium?; It is the specialized muscle of the heart that appears striated like skeletal muscle but contains shorter and branching cells, requiring its own blood supply.
What is the purpose of gap junctions in the myocardium?; They are small pores between the cells that connect the cells, allowing them to work (contract) at the same time.
What is the endocardium?; It is the very smooth inner layer that lines the chambers of the heart and heart valves.
What is the endocardium?; The very smooth inner layer which lines the chambers of the heart and heart valves, enabling friction-free flow of blood through the heart.
What supplies the heart's own blood supply?; The coronary arteries.
Where do the coronary arteries branch off from?; The aorta, which is the major vessel leaving the left ventricle.
What is the function of the septum in the heart?; It separates the right and left side of the heart, ensuring that blood flowing through the right side does not mix with blood flowing through the left side.
What are the atria in the heart?; The receiving chambers, two thin-walled chambers (one right and one left) that do not require as much muscle as ventricular (lower chambers) do not connect this way.
What are the two receiving chambers of the heart?; The atria.
What is the function of the atria?; The atria receive blood and pump it a short distance into the ventricles.
What are the two discharging chambers of the heart?; The ventricles.
What is the function of the ventricles?; The ventricles require more muscle than the atria as they pump blood a greater distance.
What are the two large veins that bring deoxygenated blood to the right atrium?; The superior vena cava and the inferior vena cava.
What is the function of the pulmonary trunk?; The pulmonary trunk carries blood from the right ventricle to the lungs.
What is the function of the left atrium?; The left atrium receives oxygenated blood from the lungs.
What is the function of the left ventricle?; The left ventricle pumps oxygenated blood to the rest of the body.
What is the composition of deoxygenated blood?; Deoxygenated blood is low in oxygen and high in carbon dioxide.
What is the largest artery in the body?; The Aorta.
What is the function of the left atrium?; To receive oxygenated blood from the lungs via 4 pulmonary veins.
What is the function of the pulmonary circulation?; To carry deoxygenated blood from the right ventricle via the pulmonary trunk to the lungs where it is oxygenated, and then return the oxygenated blood to the left side of the heart via the pulmonary veins.
What is the function of the systemic or general circulation?; To carry oxygenated blood from the left ventricle via the aorta to supply all the organs of the body, and then return deoxygenated blood to the right side of the heart via the SVC & IVC.
What is the function of veins?; To carry blood towards the heart.
What is the function of arteries?; To carry blood away from the heart.
What is the composition of blood after it leaves the lungs?; Oxygenated blood is now high in oxygen and low in carbon dioxide.
What is the composition of blood in veins?; Blood in veins is low in oxygen and high in carbon dioxide.
What is the function of the heart?; To pump blood throughout the body.
What is the pulmonary trunk?; The pulmonary trunk is the vessel that carries deoxygenated blood from the right ventricle to the lungs.
What is the function of the cardiovascular system?; It transports nutrients and gasses around the body and removes waste.
What is the mechanism of action of heart valves?; Valves permit the flow of blood in one direction only and prevent backflow of blood.
How many valves are there in the heart?; There are four valves in the heart.
What is the purpose of the right atrio-ventricular valve or tricuspid valve?; It separates the right atrium and right ventricle.
What is the purpose of the left atrio-ventricular valve or bicuspid valve?; It separates the left atrium and left ventricle.
What is the function of the pulmonary valve?; It separates the right ventricle and the pulmonary trunk, which carries blood towards the lungs.
What is the order of blood flow through the heart?; Superior & inferior vena cava (blood returning from systemic circulation) & Coronary sinus (blood from myocardium), right atrium, right ventricle, pulmonary trunk (carries blood towards lungs), pulmonary veins (blood returning from lungs), left atrium, left ventricle, aorta (carries blood into general circulation).
What is the purpose of the atrio-ventricular valve or bicuspid valve?; It separates the left atrium and left ventricle.
Where is the pulmonary valve located, and what is its function?; It sits at the base of the pulmonary trunk, and it prevents the blood from flowing back into the right ventricle.
Where is the aortic valve located, and what is its function?; It sits at the base of the aorta, and it prevents blood from flowing back into the left ventricle.
What is the purpose of the semilunar valves?; Their purpose is to prevent blood from flowing back into the ventricles when the ventricles relax.
How many cusps does the tricuspid valve have, and where is it located?; It has three cusps, and it is located between the right atrium and right ventricle.
How many cusps does the bicuspid or mitral valve have, and where is it located?; It has two cusps, and it is located between the left atrium and left ventricle.
What are the chordae tendineae, and what is their purpose?; They are tendon-like cords that anchor the valves in place and prevent them from pushing up into the atria during ventricular contraction.
What are the two distinct sounds heard when listening to the heart through a stethoscope, and what causes them?; The first sound, 'Lub,' is heard when the right and left atrio-ventricular valves close.
The second sound, 'Dub,' is heard when the semilunar valves close.; What is the difference between the sounds 'Lub' and 'Dub' heard during heart auscultation?; 'Lub' is the sound heard when the right and left atrio-ventricular valves close, while 'Dub' is heard when the pulmonary and aortic valves close.
What is the conducting system of the heart?; The conducting system of the heart is a group of electrically charged cells that stimulate the heart muscle to contract.
What is the function of the AV bundle (bundle of His) in the conducting pathway of the heart?; The AV bundle carries the impulse from the AV node to the bundle branches.
What is an electrocardiogram (ECG)?; An electrocardiogram (ECG) is a graphic representation of electrical activity in the heart that can be detected on the surface of the body.
Where is the sinoatrial (SA) node located, and what is its function?; The sinoatrial (SA) node is located in the right atrial wall and acts as the pacemaker of the heart, discharging or depolarizing spontaneously to give the characteristic rhythm, sinus rhythm.
What is the AV node?; The AV node is located at the bottom of the right interatrial septum.
What is the function of the AV bundle or bundle of His?; The AV bundle or bundle of His carries impulses from the atria to the ventricles and is located at the bottom of the interatrial septum.
Where do the right and left bundle branches course towards?; The right and left bundle branches course towards the apex through the interventricular septum.
What are Purjinkie fibers?; Purjinkie fibers penetrate the apex and ventricle walls.
What is the P wave in an ECG?; The P wave is a wave of electrical activity (depolarization) as it passes across the atria from the SA node.
What is the QRS complex in an ECG?; The QRS complex is a wave of electrical activity (depolarization) as it passes down the ventricular septum and across the walls of the ventricles.
What is the T wave in an ECG?; The T wave is the repolarization of the ventricles.
What is the P-Q interval in an ECG?; The P-Q interval is the time it takes for the impulse to reach the ventricles.
What sets the pace for the heart to contract?; The SA node or pacemaker sets the pace for the heart to contract.
What is the normal range for an adult's heart rate?; The normal range for an adult's heart rate is approximately 72 bpm.
What is bradycardia?; Bradycardia is a heart rate below 60 bpm.
What is tachycardia?; Tachycardia is a heart rate above 100 bpm.
What is the normal range for heart rate?; The normal range for heart rate is approximately 72 bpm.
What is bradycardia?; Bradycardia is a heart rate below 60 bpm.
What is tachycardia?; Tachycardia is a heart rate above 100 bpm.
What happens during the cardiac cycle?; During the cardiac cycle, the cardiac muscle contracts, the atria contract simultaneously, followed by a short pause, and then the ventricles contract simultaneously, forcing blood out of the ventricles into the blood vessels of the pulmonary system or systemic circulation.
What is systole?; Systole is the phase of the cardiac cycle when the heart contracts and forces blood out of its chambers.
What is diastole?; Diastole is the phase of the cardiac cycle when the heart relaxes and fills with blood.
What is the duration of atrial contraction during the cardiac cycle?; Atrial contraction (systole) lasts for 0.1 sec during the cardiac cycle.
What is the duration of ventricular contraction during the cardiac cycle?; Ventricular contraction (systole) lasts for 0.3 sec during the cardiac cycle.
What is the duration of complete cardiac relaxation during the cardiac cycle?; Complete cardiac relaxation (diastole) lasts for 0.4 sec during the cardiac cycle.
What is the duration of the cardiac cycle?; The cardiac cycle is 0.8 sec, which includes atrial contraction, ventricular contraction, and complete cardiac relaxation.