The Cardiovascular System, also known as the circulatory system, is a vital organ system responsible for the transport of blood, oxygen, nutrients, hormones, and waste products throughout the body. It plays a key role in maintaining homeostasis and ensuring the proper functioning of all other organ systems.
Main Components of the CVS
-
Heart
-
A muscular, four-chambered organ (right atrium, right ventricle, left atrium, left ventricle).
-
Acts as a pump to circulate blood.
-
Has valves to prevent backflow (tricuspid, pulmonary, mitral, aortic).
-
-
Blood Vessels
-
Arteries: Carry oxygen-rich blood away from the heart.
-
Veins: Return oxygen-poor blood to the heart.
-
Capillaries: Tiny vessels for exchange of gases, nutrients, and waste.
-
-
Blood
-
Consists of plasma, red blood cells, white blood cells, and platelets.
-
Red cells carry oxygen; white cells fight infection; platelets help in clotting.
Four-chambered organ
1. Right Atrium
-
Receives deoxygenated blood from the body via:
-
Superior vena cava (from upper body)
-
Inferior vena cava (from lower body)
-
-
Pumps blood into the right ventricle through the tricuspid valve.
2. Right Ventricle
-
Receives blood from the right atrium.
-
Pumps deoxygenated blood to the lungs through the pulmonary artery.
-
The pulmonary valve prevents backflow into the ventricle.
3. Left Atrium
-
Receives oxygenated blood from the lungs via the pulmonary veins.
-
Pumps blood into the left ventricle through the mitral (bicuspid) valve.
4. Left Ventricle
-
Receives oxygen-rich blood from the left atrium.
-
Pumps blood to the entire body via the aorta.
-
The aortic valve prevents blood from returning into the ventricle.
📝 Note: The left ventricle has the thickest muscular wall, because it needs to generate high pressure to send blood throughout the body.
Functions of the CVS
-
Oxygen and nutrient transport to tissues
-
Removal of carbon dioxide and waste products
-
Hormone delivery to target organs
-
Temperature regulation
-
Immunity (via white blood cells)
-
Clot formation to prevent blood loss during injury
Common Diseases of the CVS
-
Hypertension (High Blood Pressure)
-
Atherosclerosis (Artery narrowing due to plaque)
-
Coronary Artery Disease (CAD)
-
Heart Attack (Myocardial Infarction)
-
Congestive Heart Failure (CHF)
-
Arrhythmias (Irregular heartbeats)
-
Stroke (due to blocked or ruptured cerebral blood vessels)
