Cardivascular Structure
Blood Flow and Circulation
Heart Sounds and Blood Pressure
Conduction System
Heart Rate and Autonomic Nervous System
100
Name the three layers of the heart.
Epicardium: Outer layer, provides a protective layer around the heart.
Myocardium: Middle layer, composed of cardiac muscle, responsible for contraction and pumping blood.
Endocardium: Inner layer, lines the heart chambers and valves, reducing friction during blood flow.
100
Name the main blood vessels entering and leaving the heart.
Entering: Superior vena cava, inferior vena cava, and pulmonary veins.
Leaving: Pulmonary artery and aorta.
100
What causes the "lub-dub" heart sounds?
"Lub" (S1): Closing of the AV valves (tricuspid and mitral) during ventricular contraction.
"Dub" (S2): Closing of the semilunar valves (aortic and pulmonary) during ventricular relaxation.
100
Name the main components of the cardiac conduction system.
Sinoatrial (SA) node.
Atrioventricular (AV) node.
Bundle of His.
Purkinje fibers.
100
What is the average resting heart rate for an adult?
60–100 beats per minute.
200
What are the four chambers of the heart, and what is their primary function?
Right atrium: Receives oxygen-poor blood from the body.
Right ventricle: Pumps oxygen-poor blood to the lungs.
Left atrium: Receives oxygen-rich blood from the lungs.
Left ventricle: Pumps oxygen-rich blood to the body.
200
What is the difference between systemic and pulmonary circulation?
Systemic circulation: Delivers oxygen-rich blood from the heart to the body and returns oxygen-poor blood back to the heart.
Pulmonary circulation: Transports oxygen-poor blood from the heart to the lungs for oxygenation and returns oxygen-rich blood to the heart.
200
What is the normal range for systolic blood pressure in an adult?
80–120 mmHg.
200
What is the function of the SA node?
The SA node, the pacemaker of the heart, initiates electrical impulses that set the heart rate.
200
Which autonomic system decreases heart rate?
The parasympathetic nervous system.
300
What is the function of the pericardium?
The pericardium is a double-walled sac that surrounds the heart. It provides:
Protection against friction.
Anchoring of the heart in the chest cavity.
Preventing overfilling of the heart with blood.
300
How does the heart pump blood throughout the body?
What is the coordinated contraction of the atria and ventricles, pushing oxygen-poor blood through the pulmonary arteries to the lungs and oxygen-rich blood through the aorta to the body? (Lecture 2)
300
How does blood pressure change with distance from the heart?
Blood pressure decreases as it moves away from the heart due to resistance in smaller blood vessels.
300
What happens during the P wave of an ECG?
The P wave represents atrial depolarization, signaling atrial contraction.
300
What neurotransmitter is released by the parasympathetic nervous system?
Acetylcholine.
400
What are the main vessels of the heart, and what is their role?
Aorta: Carries oxygen-rich blood from the left ventricle to the body.
Pulmonary arteries: Carry oxygen-poor blood from the right ventricle to the lungs.
Pulmonary veins: Carry oxygen-rich blood from the lungs to the left atrium.
Superior and inferior vena cava: Bring oxygen-poor blood from the body to the right atrium.
400
What is blood, and how is it circulated throughout the body?
What is a fluid that circulates oxygen, nutrients, hormones, and waste products via the heart’s pumping action through systemic and pulmonary circuits?(Lecture 1)
400
What tool is used to measure blood pressure?
A sphygmomanometer (blood pressure cuff).
400
What is the role of the Bundle of His in cardiac conduction?
What is the pathway that transmits electrical impulses from the AV node to the ventricles, ensuring coordinated contraction?
400
What is the effect of epinephrine on heart rate?
Epinephrine increases heart rate and cardiac output by stimulating beta-adrenergic receptors.
500
What are the heart valves, and what is their role?
Tricuspid valve: Between the right atrium and right ventricle; prevents backflow into the atrium.
Pulmonary valve: Between the right ventricle and pulmonary artery; prevents backflow into the ventricle.
Mitral (bicuspid) valve: Between the left atrium and left ventricle; prevents backflow into the atrium.
Aortic valve: Between the left ventricle and aorta; prevents backflow into the ventricle.
500
What happens during ventricular systole?
What is the contraction of the ventricles that closes the AV valves, opens the semilunar valves, and pumps blood into the aorta and pulmonary artery?
During ventricular systole:
The ventricles contract.
The AV valves close to prevent backflow into the atria.
The semilunar valves open, allowing blood to flow into the aorta and pulmonary artery
500
Explain the role of baroreceptors in regulating blood pressure.
Baroreceptors, located in the carotid sinuses and aortic arch, detect changes in blood pressure and signal the brain to adjust heart rate and vascular resistance.
500
What is the significance of Purkinje fibers in the heart’s conduction system?
What are the specialized fibers that rapidly distribute electrical impulses throughout the ventricles, allowing for synchronized contraction?
500
How does the vagus nerve influence heart function?
The vagus nerve reduces heart rate by enhancing parasympathetic tone.