45. Which of the following is/are true concerning the opening and closing of thecardiac valves?   A. valves operate according to the pressures on either side of the valve B. valve operation is constantly being controlled by the medulla oblongata C. valve operation is determined directly by the cardiac action potential (electrical currents control the opening and closing of the valves.) D. valve operation is directly controlled by the papillary muscles within theventricular wall. E. None of the above is correct.

Q: Description 1. Microscopic blood vessels with thin, porous walls; site of gas exchange between…

A: microscopic blood vessels with small porous wall for exchange of gases between the blood and the…

Q: 117. A 45-year-old man with severe tricuspid valve prolapse undergoes a valve replacement operation.…

A:

Q: 38. The onset of Ventricular systole is associated with: A. the closing of the aortic valve B. the…

A: Heart is the pumping organ. It is responsible for pumping the blood to different parts of the body.

Q: 70. Which of the following phases of the ventricular action potential most closely coincides with…

A: The electrocardiogram is a graphic representation of the electrical activity of the heart recorded…

Q: 53 Examination of a full-term male newborn shows muffled heart sounds on the left and the point of…

A: A Cardiac silhouette is the outline of the heart seen on frontal and lateral chest X ray images. It…

Q: The two factors that assist the relatively low venous pressures in propelling blood toward the heart…

A: The circulatory system in humans has the heart, blood vessels- arteries and veins, etc. mainly. The…

Q: A Myocardial Infarction is defined as: a. Chest pain that usually starts with physical exertion and…

A: Human Heart is a four-chambered, fibro-muscular organ. There are two atria through which the heart…

Q: In a healthy young adult, what happens to cardiacoutput when heart rate increases above 160 bpm?a.…

A: Cardiac output is also known as heart output. It describes the amount of blood being pumped by the…

Q: Sketch and discuss the most important waveforms associated to the cardiac cycle and what is the…

A: A sequence of alternating contraction and relaxation of the atria and ventricles in order to pump…

Q: Which of the following would be most likely to cause pulmonary congestion?   A failure of the right…

A: Pulmonary congestion is a condition of fluid accumulation occurring in the lungs which leads to…

Q: An area of dead myocardial tissue is called: A) an infarct B) stenosis C) an induration D)…

A: Answer is A.) an infarct.

Q: nodal delay a. maintains cardiac output by allowing enough ventricular filling. b. prevents…

A: The AV node is a highly specialized conducting tissue that slows the impulse conduction considerably…

Q: 1. Explain the features of the following structures: a) High elastic fiber content in the aorta b)…

A: Introduction: The aorta is the main artery in the human body, originating from the left ventricle of…

Q: 1. The source of the electrical currents that you measured on the skin throughout a normal…

A: Note: According to the given guidelines, we are supposed to answer only one question (1st question).…

Q: 6. The diagram shows stroke volume as a function of right atrial pressure. The solid curve shows…

A:

Q: To get from the right atrium to the right ventricle, blood flows througha. the pulmonary valve.b.…

A: To get from the right atrium to the right ventricle, blood flows through the right AV valve or…

Q: 1. Which phase of Ventricular Filling increases the volume of blood in the ventricles the most?…

A: The heart is a pump that transports blood through a network of arteries. Its function is to send…

Q: (iii) A muscular wall is absent in : A. Capillary B. Venule C. Arteriole D. Vein

A: The correct option is A. Capillary

Q: 8. The closure of the tricuspid valve separates which two events in the cyclic changes of the left…

A: A single cardiac cycle includes all the events associated with one heartbeat. Thus, a cardiac cycle…

Q: 23333 The aortic valve opens at which of the following lettered points on the ventricular volume…

A: Aortic valve is present between left ventricle and aorta.  Aortic valve opens during left…

Q: A circulatory pathway in which the blood flows through two capillary beds in series - before it…

A: The circulatory pathways direct proper flow of blood through heart, lungs, and various associated…

Q: 108. A resting subject is passively tilted from the supine to the standing position. This maneuver…

A: In given scenario, the subject is sitting in a resting condition. At this stage, the subject is…

Q: Standing for a prolonged period of time can cause ... a. Decline in venous return  b. A drop in…

A: Venous return is the flow of blood from peripheral regions to back to right atrium . Factors which…

Q: a. Explain the difference in size and wall thickness of the ventricles. . b. Describe the function…

A: * The ventricles of the heart will have thicker walls than atria because blood is pumped out of…

Q: An increase in mean arterial pressure can result froma. an increase in peripheral resistance.b. an…

A: Mean arterial pressure is defined as the average arterial pressure in one cardiac cycle, which…

Q: 54. Atropine Sulfate: a. Decreases heart rate by depressing the SA note and AV node activity b.…

A: Ques 52 & 53 is not clear moreover as per our guidelines we're supposed to answer only one…

Q: 57 Which of the following is the principal factor determining the distribution of blood flow to the…

A: Blood vessels are the channels through which blood circulates inside the body ,these include  Types…

Q: 48) Pericardial arteries supply blood to the a) outer heart muscle b) tissue of the aorta c) tissue…

A: The heart is located on the slightly left side of the sternum in front of the lungs where it pumps…

Q: 3. (1) List the major blood vessels and their origins involved in coronary circulation. (ii) At what…

A: Coronary circulation is the movement of blood throughout the vessels that supply the heart muscle.…

Q: Stable angina is defined as: a. Chest pain that usually starts with physical exertion and is…

A: Cardiac physiology plays a critical role in the appropriate perfusion of organs in our body with…

Q: 7. The P-Wave in the electrocardiogram...   A)Gives information about the oxygenation content of…

A: The correct answer is Option D.Each cardiac cycle is of 0.8 seconds. Electrocardiogram (ECG) is a…

Q: 16 A 62-year-old man comes to the emergency department because of chest pain. Cardiac…

A: The two main coronary arteries are the right coronary artery (RCA) and the left main coronary artery…

Q: 1- The left ventricular wall of the heart is thicker than the right wall in order to…

A: Introduction :- Near the heart base, the ventricular wall is thickest, and it thins out to 1-2 mm at…

Q: 46. It is generally accepted that a relatively low diastolic vascular pressure is more important…

A: Diastolic vascular pressure is the lowest arterial pressure measured during a cardiac cycle and is…

Q: The normal pacemaker of the heart is the ______.   A sinoatrial node   B left atrium   C…

A: Heart is an important organ that pumps blood. Heart is myogenic in nature meaning it is capable of…

Q: 111. A healthy 23-year-old woman engages in strenuous dynamic exercise for 30 minutes. Which of the…

A:

Q: During the period of isovolumic contraction: A. the AV-valves are open and the aortic & pulmonary…

A:

Q: A. begins with closure of the AV-valves and ends with opening of the valves B. begins with opening…

A: There are two types of atrioventricular valves. The mitral and the tricuspid valves, also known as…

Q: Which of the following is/are true concerning the opening and closing of the cardiac valves? A.…

A: Backward blood flow is prevented by the valves. On each end of the two ventricles are flaps that act…

Q: The onset of Ventricular diastole is associated with: A. the closing of the aortic valve B. the…

A: Human heart is composed of two auricles (atria) and two ventricles. Cardiac cycle consists of…

Q: Which of the choices below best describes the systemic circulation of blood? a. The flow of blood…

A: The circulatory system is one of the most essential systems in the body. The function of the…

Q: One difference between the semilunar valves and the atrioventricular valves is that only the…

A: The valves that are found between the atria and ventricles are termed as atrioventricular valves,…

Q: Which of the following statements is true?a. The longer the vessel, the lower the resistanceand the…

A: Blood is a fluid connective tissue that circulates all over the body delivering nutrients and oxygen…

Q: 6. In the carotid arteriogram, obstruction of the vessel at X is most likely to result in which of…

A: Introduction Carotid arteriogram:- It is an X-ray of the blood vessels to see the blood vessels in…

Dissection

Dissection is the process of cutting up the tissue of a dead or live animal or plant, to do anatomical studies and surgical treatments. The purpose of dissection is to learn more about the overall structure of organs and organ systems and thereby understand the physiology of the organism.