Ch. 22 Heart

Explain how a heart muscle impulse travels from the SA node through the heart

The muscle impulse spreads via gap junction between cardiac muscle cells throughout both the atria and to the AV node via intermodal pathways.

Explain the role of the sinoatrial node

The heartbeat is initiated by the specialized cardiac muscle cells of the SA node, which are located in the posterior wall of the right atrium. The cells of the SA node act as a pacemaker, the rhythmic center that establishes the pace for cardiac activity.

What is the function of the superior vena cava?

The large vein which returns blood to the heart from the head, neck, and both upper limbs

What is the structure and function of the atria?

The left and right atria are thin-walled chambers located superiorly. The anterior part of each atrium is a wrinkled, flaplike extension called an auricle. The atria receives blood returning to the heart through both circulations: The right atrium receives blood from the systemic circulation and the left receives from the pulmonary circulation.

What is the structure and function of the ventricles?

The left and right ventricles are the inferior chambers of the heart. Right ventricle pumps blood into pulmonary circulation, left ventricle pumps blood into systemic circulation via aorta

What are the tendons that connect the valves to the muscles?

Chordae tendinae

What are the flaps on the front of atria called?

Auricles

What is the function of chordae tendinae?

Cord like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve

What does the coronary sinus do?

Drains directly into the right atrium of the heart

If you place a probe in the aorta, into what chamber will it exit?

Left ventricle

What is another name for the bicuspid valve?

Mitral valve

What is systemic circulation?

Moves oxygenated blood from the left side of the heart.

What is the function of papillary muscles?

Muscles located in the ventricles of the heart. They contract to prevent inversion or prolapse of the valves during systole.

What is the function of the AV node?

Normally slows conduction of the impulse as it travels from the atria to the ventricles, providing a delay between activation and contraction of the ventricles.

What muscles hold the valves in place?

Papillary muscles

What is the only artery in the body that carries deoxygenated blood?

Pulmonary artery

What is the function of the semilunar valves?

Pulmonary semilunar valve- Prevents backflow of blood into right ventricle when ventricles relax Aortic semilunar valve- Prevents backflow of blood into left ventricle when ventricles relax

The large vessel on the front of the heart that lies in front of the aorta is the...

Pulmonary trunk

What is the function of the bundle of his(atrioventricular bundle)

Receives impulses from the AV node and extends into the interventricular septum before dividing into left and right bundles.

What is the function of pulmonary veins?

Responsible for carrying oxygenated blood from the lungs back to the left atrium. Different from the rest of the veins, which are used to carry deoxygenated blood from the rest of the body back to the heart.

What is the function of the inferior vena cava?

Returns blood to the heart from the lower part of the body.

What is the function of the atrioventricular valves?

Right Atrioventricular valve- prevents backflow of blood into right atrium when ventricles contract Left Atrioventricular valve- prevents backflow of blood into left atrium when ventricles contract

The superior and inferior vena cava enter into what chamber of the heart?

Right Atrium

What is the basic pattern of blood flow?

Right side of the heart-> lungs-> left side of the heart-> systemic tissues of the body-> back to the right side

What is the function of the purkinje fibers?

Send nerve impulses to the cells in the ventricles of the heart and cause them contract and pump blood either to the lungs or the rest of the body.

What is the difference between systole and diastole?

Systole-Maximum pressure your heart exerts while beating. Semilunar valves open, blood flows into arteries, contraction of ventricles Diastole-The amount of pressure in your arteries between beats. Relaxation of ventricles, blood flows into ventricles from atria

What is the function of the heart?

To move nutrients and oxygen throughout the body

What is pulmonary circulation?

conveys deoxygenated blood from the right side of the heart through the blood vessels to the lungs for the pickup of oxygen and the release of carbon dioxide.

Define pericarditis

inflammation of the pericardium