Q1. Label the following external and internal parts of the sheep heart: Pericardium, Adipose, Interventricular Sulcus, Coronary blood vessels, Apex, Aorta, Left atrium, Right atrium, Pulmonary artery, Superior vena cava, Inferior vena cava, Pulmonary veins, Interventricular septum, Right ventricle, Left ventricle, Bicuspid valve, Tricuspid valve.

Background

Topic: Heart Anatomy

This question tests your knowledge of the anatomical structures of the heart, both external and internal, and your ability to identify them on a specimen or diagram.

Key Terms:

• Pericardium: The double-walled sac that encloses the heart.

• Adipose: Fat tissue, often found on the surface of the heart.

• Interventricular Sulcus: Groove on the heart's surface marking the boundary between the ventricles.

• Coronary blood vessels: Vessels that supply blood to the heart muscle itself.

• Apex: The pointed end of the heart, usually directed leftward and downward.

• Aorta: The main artery carrying oxygenated blood from the left ventricle to the body.

• Left/Right Atrium: Upper chambers of the heart that receive blood.

• Left/Right Ventricle: Lower chambers that pump blood out of the heart.

• Pulmonary artery: Carries deoxygenated blood from the right ventricle to the lungs.

• Superior/Inferior vena cava: Large veins bringing deoxygenated blood from the body to the right atrium.

• Pulmonary veins: Bring oxygenated blood from the lungs to the left atrium.

• Interventricular septum: Wall separating the left and right ventricles.

• Bicuspid (mitral) valve: Valve between the left atrium and left ventricle.

• Tricuspid valve: Valve between the right atrium and right ventricle.

Step-by-Step Guidance

1. Start by reviewing diagrams or models of the heart to familiarize yourself with the location of each structure listed above.

2. Identify the external features first: pericardium, adipose tissue, interventricular sulcus, coronary vessels, and apex. Note their positions relative to the heart's orientation.

3. Next, locate the major blood vessels entering and leaving the heart: aorta, pulmonary artery, superior and inferior vena cava, and pulmonary veins. Consider where they connect to the heart chambers.

4. Move to the internal anatomy: identify the four chambers (left/right atria and ventricles) and the interventricular septum that separates the ventricles.

5. Finally, locate the valves: the bicuspid (mitral) valve is between the left atrium and ventricle, and the tricuspid valve is between the right atrium and ventricle. Think about the direction of blood flow to help you place these.

Try labeling a diagram or model on your own before checking the answer!

Q2. Where is blood deoxygenated and where is it oxygenated in the heart and blood vessels?

Background

Topic: Oxygenation of Blood in the Heart

This question tests your understanding of the flow of blood through the heart and the points at which it is oxygenated or deoxygenated.

Key Terms:

• Deoxygenated blood: Blood low in oxygen, high in carbon dioxide.

• Oxygenated blood: Blood rich in oxygen, low in carbon dioxide.

• Pulmonary circuit: Pathway from the heart to the lungs and back, where blood is oxygenated.

• Systemic circuit: Pathway from the heart to the body and back, where oxygen is delivered to tissues.

Step-by-Step Guidance

1. Recall that blood returning from the body is deoxygenated and enters the right atrium via the superior and inferior vena cava.

2. This deoxygenated blood moves from the right atrium to the right ventricle, and then is pumped out through the pulmonary artery to the lungs.

3. In the lungs, blood picks up oxygen and releases carbon dioxide, becoming oxygenated.

4. Oxygenated blood returns to the heart via the pulmonary veins, entering the left atrium, then moves to the left ventricle, and is pumped out through the aorta to the body.

5. Think about which chambers and vessels carry deoxygenated versus oxygenated blood as you trace this pathway.

Try to identify the oxygenation status of each chamber and vessel before revealing the answer!

Q3. What is the difference between the systemic and pulmonary circuits?

Background

Topic: Circulatory Pathways

This question tests your understanding of the two main circuits of blood flow in the body and their functions.

Key Terms:

• Pulmonary circuit: Carries blood from the heart to the lungs and back to the heart.

• Systemic circuit: Carries blood from the heart to the rest of the body and back.

Step-by-Step Guidance

1. Define the pulmonary circuit: it starts at the right ventricle, goes to the lungs via the pulmonary artery, and returns to the left atrium via the pulmonary veins.

2. Define the systemic circuit: it starts at the left ventricle, goes to the body via the aorta, and returns to the right atrium via the vena cavae.

3. Consider the function of each circuit: pulmonary circuit exchanges gases in the lungs; systemic circuit delivers oxygen to tissues and removes waste.

4. Think about the oxygenation status of blood in each circuit and the direction of flow.

Try to summarize the differences before revealing the answer!

Q4. What is the order of the structures that blood flows through as it moves through the heart?

Background

Topic: Blood Flow Pathway

This question tests your ability to trace the path of blood through the heart, including all chambers, valves, and major vessels.

Key Terms:

• Right atrium

• Tricuspid valve

• Right ventricle

• Pulmonary valve

• Pulmonary artery

• Pulmonary veins

• Left atrium

• Bicuspid (mitral) valve

• Left ventricle

• Aortic valve

• Aorta

Step-by-Step Guidance

1. Start with deoxygenated blood entering the right atrium from the superior and inferior vena cava.

2. Blood passes through the tricuspid valve into the right ventricle.

3. From the right ventricle, blood is pumped through the pulmonary valve into the pulmonary artery and travels to the lungs.

4. Oxygenated blood returns from the lungs via the pulmonary veins to the left atrium.

5. Blood passes through the bicuspid (mitral) valve into the left ventricle, then is pumped through the aortic valve into the aorta and out to the body.

Try to write out the full sequence before revealing the answer!