PATH OF BLOOD THROUGH THE HEART

Question 1

Blood

Answer 1

low in oxygen and high in carbon dioxide

Question 2

Vena cavae

Answer 2

Two large veins supplying blood to the right atrium.
A. Superior vena cava
B. Inferior vena cava

Question 3

Coronary sinus

Answer 3

Smaller vein which drains blood from the heart wall into the right atrium

Question 4

Tricuspid valve

Answer 4

one of two atrioventricular valves (A-V valves); functions to ensure one-way blood flow between the atria and ventricles

Question 5

Chordae tendineae

Answer 5

strong, fibrous strings attaching to the cusps of the tricuspid valve on the ventricular side.

Strings arise from small mounds of cardiac muscle tissue called papillary muscles which project inward from the ventricular walls

Question 6

Step 1

Answer 6

blood enters the right atrium through the vena cavae and coronary sinus

Question 7

Step 2

Answer 7

As the wall of the right atrium contracts, blood passes through the tricuspid valve into the right ventricle.

As the tricuspid valve closes, the papillary muscles pull on the chordae tendineae and prevent the cusps from swinging back into the atrium

When the right ventricular wall contracts, the tricuspid valve closes, preventing back flow into the right atrium, and the blood moves through the pulmonary valve and into the pulmonary trunk and its branches - divides into left and right pulmonary arteries that lead to the lungs.

Question 8

Step 3

Answer 8

As the ventricle contracts, the valve opens; when the ventricle relaxes, the valve closes.

Question 9

Step 4

Answer 9

From the pulmonary arteries, the blood enters the capillaries of the alveoli of the lungs.

Gas exchanges occur between the blood in the capillaries and air in the alveoli.

Freshly oxygenated blood, now high in oxygen and low in carbon dioxide concentrations, returns to the heart through the pulmonary veins, which lead to the left atrium.

Four pulmonary veins - two from the right lung and two from left lung bring blood to the left atrium.

Question 10

Step 5

Answer 10

Blood passes from the left atrium into the left ventricle through the bicuspid valve.

Question 11

Step 6

Answer 11

When the left ventricle contracts, the bicuspid valve closes and the blood must exit through a large artery - the aorta.

As the left ventricle contracts, the aortic valve is forced open allowing blood to leave.

When the ventricle relaxes, the aortic valve closes and prevents blood from backflow into the ventricle.

**The entire system is designed to facilitate one-way blood flow through the heart, preventing backflow.

Question 12

pulmonary valve

Answer 12

allows blood to leave the right ventricle and prevents backflow into the ventricular chamber when the ventricle relaxes

Question 13

Bicuspid valve (mitral valve)

Answer 13

prevents backflow of blood into the left atrium from the ventricle during ventricular contraction(valve closes during ventricular contraction).

Question 14

Mitral valve prolapse

Answer 14

may result in regurgitation of blood into the left atrium.

Prolapse is due to one or both of the cusps stretching and bulging into the left atrium during ventricular contraction.

Symptoms of MVP include chest pain, fatigue, palpitations, and anxiety.

Question 15

Murmur

Answer 15

heard in a stethoscope is the blood moving back through the valve into the left atrium.

Question 16

Papillary muscles and chordae tendineae

Answer 16

prevent the cusps of the bicuspid valve from swinging back into the left atrium during ventricular contraction

**Valve closes due to pressure differences created by ventricular contractions and relaxation.