the cardiovascular system & blood system

How many times does the heart contract in a normal day?

Approximately 86,400 times.

What is the estimated number of heart contractions in a year?

About 31.5 million contractions.

What is the estimated number of heart contractions during an average lifetime?

Approximately 2.4 billion contractions.

How much blood does the heart pump per day?

5,000-6,000 liters, or about 2,000 gallons.

Why is circulation important for the body?

Every cell requires oxygen and nutrients to stay alive.

What is the function of the pulmonary circuit?

To send blood to the lungs for oxygenation.

What is the function of the systemic circuit?

To deliver oxygen to the rest of the body.

What is the first part of the cardiovascular sequence that returns deoxygenated blood?

Superior & Inferior vena cava and coronary sinus.

What is the role of the right atrium?

To receive deoxygenated blood from the vena cava and contract to push blood into the right ventricle.

What valve opens to allow blood flow from the right atrium to right ventricle?

Tricuspid valve.

What is the role of the right ventricle?

Pumps deoxygenated blood to the lungs and contracts to push blood through the pulmonary valve.

What is the structure known as the normal pacemaker of the heart?

Sinoatrial node.

What is tachycardia?

A fast heart rate.

What is bradycardia?

A low heart rate.

What is fibrillation?

A condition where muscle tissue does not fully contract.

What is cardioversion?

A method to restore the heart to a normal rhythm.

Which ion are the heart's conducting cells most sensitive to?

Potassium (K).

What is the longest vein in the body?

The great saphenous vein.

What are the normal heart rates for a fetus, newborn, and adult?

Fetus: 144, Newborn: 140, Adult: 60-99.

What percentage of blood is red blood cells?

About 45% of blood, with 95.1% of that being red blood cells.

What is hematocrit?

The percentage by volume of red blood cells in a sample of whole blood.

What makes up the formed elements in blood?

Red blood cells, white blood cells, and platelets.

What type of blood cells lack a nucleus when mature?

Red blood cells.

What is the normal white blood cell count per microliter of blood?

3,500 to 10,500 white blood cells.

How are platelets best described?

As pieces of cell fragments.

What are biliverdin and bilirubin?

Biliverdin is a green pigment and bilirubin is an orange pigment formed from the breakdown of red blood cells, both broken down by the liver.