Anatomy and Physiology 2- Heart (study questions)

What are the outer coverings of the heart?

The outer covering of the heart are the pericardium, which has two main layers: the fibrous pericardium (a tough outer layer) and the serous pericardium (a thinner inner layer that includes the parietal and visceral layers)

As blood flows through the heart, what path does it take? What chambers and valves does it flow through?

Blood flows through the heart in the following path:

1. It enters the right atrium from the body.

2. It moves through the tricuspid valve into the right ventricle.

3. It is pumped through the pulmonary valve to the lungs to get oxygen.

4. It returns to the left atrium from the lungs.

5. It moves through the mitral valve into the left ventricle.

6. It is pumped through the aortic valve out to the rest of the body.

What make up the atrioventricular valves and what is their function?

The atrioventricular valves are made up of flaps or leaflets of tissue. Their function is to prevent the backflow of blood from the ventricles to the atria when the heart pumps

What makes the heart sounds?

The heart sounds are made by the closing of the heart valves. The “lub” sound happens when the atrioventricular valves (tricuspid and mitral valves) close, and the “dub” sound happens when the semilunar valves (aortic and pulmonary valves) close.

What are the vessels that carry blood to and from the heart?

The vessels that carry blood to and from the heart are:

• Arteries: These carry blood away from the heart. The main artery is the aorta.

• Veins: These carry blood back to the heart. The main veins are the superior and inferior vena cava.

• Pulmonary arteries: These carry blood from the heart to the lungs.

• Pulmonary veins: These bring blood from the lungs back to the heart.

How are cardiac muscle cells different from skeletal muscle cells?

Cardiac muscle cells are different from skeletal muscle cells in several ways. Cardiac muscle cells are found only in the heart and are responsible for pumping blood throughout the body. They can contract on their own without needing signals from the brain, thanks to special cells that generate electrical impulses. These cells are also interconnected, allowing the heart to contract in a coordinated way. In contrast, skeletal muscle cells are attached to bones and are used for voluntary movements. They require signals from the brain to contract and are not as interconnected as cardiac muscle cells.

What is the SA node and the AV node? what do these do?

The SA node (sinoatrial node) is often called the heart’s natural pacemaker. It sends out electrical signals that make the heart beat. The AV node (atrioventricular node) is like a relay station; it takes the signals from the SA node and passes them to the lower parts of the heart, ensuring the heart beats in a coordinated way.

What is atrial fibrillation, ventricular fibrillation, heart block, heart attack and cardiac arrest?

Atrial fibrillation is a type of irregular heartbeat that starts in the upper chambers of the heart. Ventricular fibrillation is a more serious irregular heartbeat that occurs in the lower chambers and can be life-threatening. Heart block is a problem where the electrical signals that control the heartbeat are slowed down or blocked. A heart attack happens when the blood supply to a part of the heart is blocked, causing damage to the heart muscle. Cardiac arrest is when the heart suddenly stops beating, which can lead to death if not treated immediately.

What are the main parts of an EKG trace?

The main parts of an EKG trace are:

1. P wave: This shows the electrical activity in the atria (the upper chambers of the heart) as they contract.

2. QRS complex: This shows the electrical activity in the ventricles (the lower chambers of the heart) as they contract.

3. T wave: This shows the ventricles as they relax after contracting.

What is cardiac output and stroke volume?

Cardiac output is the amount of blood the heart pumps in one minute. Stroke volume is the amount of blood pumped by the heart in one beat.

What are ways in which cardiac output can increase (or decrease)?

Cardiac output can increase when the heart beats faster or pumps more blood with each beat. This can happen during exercise or when you’re excited. It can decrease when the heart beats slower or pumps less blood with each beat, which can happen when you’re at rest or if you have certain heart conditions.