Unit 13: Circulatory System

Systemic Circulation

Delivers blood to all body cells and carries away waste.

Pulmonary Circulation

Eliminates carbon dioxide and oxygenates blood through the lungs.

Heart Size

About 14 cm x 9 cm, roughly the size of a fist.

Mediastinum

The area where the heart is located, between the 2nd rib and the 5th intercostal space.

Apex of the Heart

The distal end of the heart.

Coronary Arteries

Blockages here can cause a heart attack.

Fibrous Pericardium

Encloses the heart in a two-layered structure.

Pericardial Cavity

Contains fluid to reduce friction around the heart.

Epicardium

Outer layer of the heart that reduces friction.

Myocardium

Middle layer of the heart, primarily made of cardiac muscle.

Endocardium

Thin inner lining within the chambers of the heart.

Double Pump

The heart functions as a double pump for double-loop circulation.

Atria

The two thin upper chambers of the heart that receive blood returning through veins.

Ventricles

The two thick muscular lower chambers that pump blood out through arteries.

Septum

Muscular wall that separates the left and right sides of the heart.

Valves of the Heart

Allow one-way flow of blood, including 2 atrioventricular and 2 semilunar valves.

Bicuspid Valve

Also known as the left atrioventricular valve or mitral valve.

Tricuspid Valve

Also known as the right atrioventricular valve.

Aortic Semilunar Valve

Valve between the left ventricle and the aorta.

Pulmonary Semilunar Valve

Valve between the right ventricle and the pulmonary artery.

Chordae Tendineae

Fibrous cords attaching the cusps of the atrioventricular valves to the papillary muscles.

Papillary Muscles

Muscles that help anchor the valves and prevent backflow during ventricular contraction.

Ventricular Septal Defect

A defect that is often referred to as a 'hole in the heart'.

Hemostasis

The process of stopping bleeding through coagulation and clotting of the blood.

Platelets

Help initiate the formation of blood clots and close breaks in damaged blood vessels.

Plasma

The liquid portion of blood, consisting of 92% water and containing proteins, nutrients, and hormones.

Albumins

Proteins in plasma that help regulate blood pressure.

Globulins

Proteins that transport antibodies in the blood.

Fibrinogen

A protein in plasma essential for blood clotting.

Thrombin

An enzyme that causes blood clotting by converting fibrinogen to fibrin.

Thrombus

An abnormal blood clot.

Embolus

A blood clot that has moved from its original location.

Pulmonary Embolism

Occurs when a blood clot travels to the lungs.

Vitamin K Deficiency Bleeding (VKDB)

A bleeding disorder prevented by vitamin K injections in newborns.

Hemophilia

A genetic disorder also known as 'bleeder’s disease' where blood does not clot.

Phlebotomist

A person trained to draw blood from a patient.

Erythrocytes

Red blood cells that carry oxygen throughout the body.

Leukocytes

White blood cells involved in the immune response.

Thrombocytes

Platelets that assist in blood clotting.

Hypochromia

A condition where red blood cells are pale, indicating anemia.

Spleen Functions

Filters blood, removes old blood cells, recycles iron, and makes antibodies.

Acute Lymphoblastic Leukemia (ALL)

The most common type of childhood leukemia.

Beta-Thalassemia

An inherited disorder affecting the blood’s ability to carry oxygen.

EPO (Erythropoietin)

A hormone that increases the production of red blood cells.

Sickle Cell Disease

A genetic disorder characterized by abnormal hemoglobin leading to misshapen red blood cells.