Human Anatomy: Circulatory System

In the correct answer, the cardiac cycle is 0.8 seconds, the average bpm is 75, and the average cardiac output is 75 mL. The other options provided different values for these parameters, making them incorrect.

Cardiac output refers to the volume of blood pumped out of the left ventricle per minute. The correct equation for cardiac output is calculated by multiplying the heart rate (beats per minute) by the stroke volume (volume of blood ejected by each ventricle during one contraction).

The 'lub-dub' sounds heard in the heartbeat are caused by the closing of heart valves. The 'lub' sound is specifically caused by the closure of the AV valves, while the 'dub' sound is caused by the closure of the semilunar valves.

A heart murmur is an abnormal sound heard during a heartbeat that can indicate a heart defect caused by the backflow of valves. It is not related to respiratory infections, high blood pressure, or muscle strain.

During relaxation, AV valves are open to allow blood flow from the atria to the ventricles, while semilunar valves are closed to prevent blood from flowing back into the ventricles.

Semilunar valves are located between the ventricles and the main arteries leaving the heart. The aortic semilunar valve guards the opening between the left ventricle and the aorta, while the pulmonary semilunar valve guards the opening between the right ventricle and the pulmonary artery.

Arteries are primarily composed of elastic connective tissue, which allows them to expand and contract with the beating of the heart. Muscular, Nervous, and Adipose tissues are not the primary components of arteries.

When there is a blockage of blood flow to the brain, it can lead to a stroke. Blockage in arteries making it harder for blood to flow can result in high blood pressure. Heart attack, aneurysm, and deep vein thrombosis are also serious conditions caused by blockages, but they are not specifically related to the scenarios described in the question.

The coronary artery is responsible for supplying blood to the heart muscle itself, while the pulmonary artery carries blood from the heart to the lungs, the carotid artery supplies blood to the brain, and the femoral artery supplies blood to the lower extremities.

Heart attacks are primarily caused by blockages in the coronary arteries, restricting blood flow and oxygen to the heart muscle. Smoking cigarettes, excessive exercise, and high sugar consumption may contribute to heart disease, but they are not direct causes of a heart attack like blockages in the arteries.

The correct treatments for a heart attack involve medical interventions rather than alternative or complementary therapies such as meditation, yoga, herbal remedies, or homeopathy.

The systematic circuit refers to the pathway of blood flow from the heart to the rest of the body, delivering oxygen and nutrients to various tissues and organs. It plays a crucial role in maintaining overall health and proper functioning of the body.

The term 'pulmonary circuit' specifically refers to the pathway of blood from the heart to the lungs for oxygenation.

The circulatory system plays a crucial role in transporting nutrients to cells and carrying away metabolic wastes for excretion. Therefore, the correct answer is 'Nutrients; wastes.' On the other hand, oxygen is carried by red blood cells and carbon dioxide is removed through respiration, making it an incorrect option. Hormones and enzymes are typically transported through the endocrine and digestive systems, respectively, not the circulatory system. Water and minerals are important for various bodily functions, but they are not the primary components carried by the circulatory system.

The correct sequence in the circulatory system involves blood flowing from arteries to arterioles to capillaries to venules and finally to veins for proper circulation.

A pulse is the rhythmic expansion and contraction of the arteries due to the pumping action of the heart.

Blood pressure is determined by the amount of blood the heart pumps and the resistance to blood flow in the blood vessels.

Blood pressure is the measurement of the force of blood pushing against blood vessel walls. Systolic pressure refers to the pressure in the arteries when the heart beats, while diastolic pressure is the pressure in the arteries when the heart is resting between beats.

The heart is located in the thoracic cavity, between the lungs and above the diaphragm, not in the abdominal, pelvic, or cranial cavities.

The correct term for the cardiac tissue found only in the heart is myocardium, which is responsible for the contraction of the heart muscle and pumping of blood throughout the body.

Veins carry blood to the heart with low oxygen levels, while arteries carry blood away from the heart with high oxygen levels.

A septum is a thick wall that separates two chambers or spaces. The other incorrect answers are not specific terms for a thick wall separating a chamber.

CO2-rich blood returns to the heart through the superior and inferior vena cava after circulating through the body's tissues. The other options mentioned are not the correct entry points for CO2-rich blood into the heart.

The pulmonary veins carry oxygen-rich blood from the lungs back to the heart. Specifically, they empty into the left atrium of the heart, where the blood will then be pumped into the left ventricle and out to the rest of the body through the aorta. The right ventricle receives deoxygenated blood from the body via the vena cava, while the aorta is responsible for distributing oxygenated blood to the rest of the body. The superior vena cava brings deoxygenated blood from the upper body back to the heart.

The bicuspid or mitral valve is located between the left atrium and left ventricle, allowing blood to flow from the atrium to the ventricle while preventing backflow. The tricuspid valve is located between the right atrium and right ventricle, the pulmonary valve is located between the right ventricle and pulmonary artery, and the aortic valve is located between the left ventricle and aorta.

The tricuspid valve is located between the right atrium and right ventricle, allowing blood to flow in one direction. The pulmonary valve connects the right ventricle to the pulmonary artery, the aortic valve connects the left ventricle to the aorta, and the mitral valve connects the left atrium and left ventricle.

The correct answer is Sinoatrial, located in the right atrium below the superior vena cava. The other options refer to different parts of the heart that do not serve as the internal pacemaker.

The AV valves are specifically called bicuspid and tricuspid valves as they are located between the atria and ventricles in the heart, ensuring unidirectional blood flow.

Cardiac fiber muscles send the SA signal to the apex of the heart, which is located at the bottom of the heart. The apex is responsible for coordinating the heartbeat and ensuring proper circulation of blood throughout the body. The aorta, left ventricle, and right atrium are important components of the heart, but they do not receive the SA signal from the cardiac fiber muscles.