Biology Grade 11 Heart

What is the main function of the heart in the human body?

• To digest food and absorb water

• To pump blood and circulate oxygen and nutrients

• To regulate body temperature and control emotions

• To pump air and circulate nutrients

Describe the structure of the human heart including its chambers and valves.

• The heart has two valves: tricuspid valve and mitral valve.

• The human heart has four chambers: two atria and two ventricles. The right atrium receives deoxygenated blood from the body, which then flows into the right ventricle. The right ventricle pumps the blood to the lungs for oxygenation. The oxygenated blood returns to the heart in the left atrium, then passes into the left ventricle. The left ventricle pumps the oxygenated blood out to the rest of the body. The heart has four valves: tricuspid valve, pulmonary valve, mitral valve, and aortic valve, which ensure blood flows in the correct direction.

• The human heart has three chambers: one atrium and two ventricles.

• The right atrium receives oxygenated blood from the body.

Explain the process of the cardiac cycle and the different phases involved.

• The cardiac cycle involves only one phase called diastole

• Atrial systole occurs during ventricular diastole

• The cardiac cycle involves systole (contraction) and diastole (relaxation) phases, which are further divided into atrial systole, ventricular systole, early diastole, and late diastole.

• Late diastole is the phase where the heart is fully contracted

How does blood circulate through the heart and the rest of the body?

• Blood circulates through the heart and the rest of the body by following the path from the right atrium to the right ventricle, then to the lungs, back to the left atrium, and finally to the left ventricle before being pumped out to the body.

• Blood circulates through the heart by bypassing the lungs entirely

• Blood circulates through the heart by jumping directly from the right atrium to the left ventricle

• Blood circulates through the body by flowing in reverse from the left ventricle to the right atrium

What is the role of the atria and ventricles in the heart's pumping action?

• Atria contract to pump blood out of the heart, while ventricles receive blood and push it into the atria.

• Atria and ventricles contract simultaneously to push blood in and out of the heart.

• Atria and ventricles both receive blood and pump it out of the heart.

• Atria receive blood and contract to push it into the ventricles, while ventricles contract to pump blood out of the heart.

Discuss the importance of the sinoatrial node (SA node) in regulating the heart's rhythm.

• The SA node plays a role in digestion by secreting enzymes.

• The SA node controls the body's temperature regulation.

• The SA node is crucial in setting the heart's rhythm by generating electrical impulses that coordinate the heart's contractions.

• The SA node is responsible for filtering blood in the heart chambers.

Identify the major blood vessels connected to the heart and their respective functions.

• Coronary arteries, carotid arteries, jugular veins

• Brachial artery, iliac veins, popliteal vein

• Aorta, pulmonary arteries, superior vena cava, inferior vena cava, pulmonary veins

• Hepatic artery, renal veins, femoral vein

What are the differences between pulmonary circulation and systemic circulation?

• Pulmonary circulation involves the flow of blood between the heart and the lungs, while systemic circulation involves the flow of blood between the heart and the rest of the body.

• Pulmonary circulation occurs in the veins, while systemic circulation occurs in the arteries.

• Pulmonary circulation involves the flow of blood between the heart and the brain, while systemic circulation involves the flow of blood between the heart and the lungs.

• Pulmonary circulation is responsible for delivering oxygenated blood to the body, while systemic circulation is responsible for oxygenating the blood.

Describe the pathway of blood flow through the heart, starting from the vena cava.

• Vena cava -> Left atrium -> Tricuspid valve -> Right ventricle -> Pulmonary valve -> Pulmonary artery -> Lungs -> Pulmonary veins -> Right atrium -> Mitral valve -> Left ventricle -> Aortic valve -> Aorta

• Vena cava -> Right atrium -> Tricuspid valve -> Right ventricle -> Pulmonary valve -> Pulmonary artery -> Lungs -> Pulmonary veins -> Left atrium -> Mitral valve -> Left ventricle -> Aortic valve -> Aorta

• Vena cava -> Right atrium -> Tricuspid valve -> Left ventricle -> Pulmonary valve -> Pulmonary artery -> Lungs -> Pulmonary veins -> Left atrium -> Mitral valve -> Right ventricle -> Aortic valve -> Aorta

• Vena cava -> Right atrium -> Mitral valve -> Right ventricle -> Pulmonary valve -> Pulmonary artery -> Lungs -> Pulmonary veins -> Left atrium -> Tricuspid valve -> Left ventricle -> Aortic valve -> Aorta

Explain the significance of coronary circulation in providing oxygen to the heart muscle.

• Coronary circulation has no impact on heart muscle oxygenation

• Coronary circulation only delivers carbon dioxide to the heart muscle

• The heart muscle does not require oxygen for proper function

• Coronary circulation plays a vital role in delivering oxygen to the heart muscle, which is essential for its metabolic needs and overall function.