Overview of the Circulatory System

Overview of the Circulatory System

• Comprises the heart, blood vessels, and blood.
• Responsible for transporting oxygen, nutrients, hormones, and waste products throughout the body.

Components

1. Heart

   • Muscular organ that pumps blood.
   • Divided into four chambers:
     • Right Atrium
     • Right Ventricle
     • Left Atrium
     • Left Ventricle

2. Blood Vessels

   • Arteries: Carry oxygenated blood away from the heart (except pulmonary arteries).
   • Veins: Carry deoxygenated blood back to the heart (except pulmonary veins).
   • Capillaries: Microscopic vessels where gas and nutrient exchange occurs.

3. Blood

   • Composed of red blood cells, white blood cells, platelets, and plasma.
   • Red blood cells contain hemoglobin to transport oxygen.

Blood Flow through the Heart

1. Deoxygenated blood enters the Right Atrium via superior and inferior vena cava.
2. Blood flows from the Right Atrium to the Right Ventricle through the tricuspid valve.
3. Right Ventricle pumps blood to the lungs via the pulmonary artery for oxygenation.
4. Oxygenated blood returns to the Left Atrium through the pulmonary veins.
5. Blood flows from the Left Atrium to the Left Ventricle through the bicuspid (mitral) valve.
6. Left Ventricle pumps oxygenated blood to the rest of the body via the aorta.

Function of the Circulatory System

• Transportation: Moves oxygen, carbon dioxide, nutrients, hormones, and waste.
• Regulation: Maintains body temperature, pH balance, and fluid balance.
• Protection: Involves white blood cells and antibodies, contributing to the immune response.

Cardiac Cycle

• Systole: Contraction phase of the heart; ventricles pump blood out.
• Diastole: Relaxation phase; heart fills with blood.

Electrical Conduction

• Sinoatrial (SA) Node: Pacemaker that initiates heartbeat.
• Atrioventricular (AV) Node: Delays impulse to allow atrial contraction before ventricles contract.
• Bundle of His and Purkinje Fibers: Conduct impulses throughout the ventricles for coordinated contraction.

Types of Circulation

• Pulmonary Circulation: Blood flow between the heart and lungs.
• Systemic Circulation: Blood flow between the heart and the rest of the body.

Disorders

• Coronary Artery Disease: Blockage of coronary arteries reducing blood flow to the heart.
• Heart Failure: The heart's inability to pump sufficiently.
• Arrhythmias: Abnormal heart rhythms due to electrical conduction issues.
• Hypertension: Elevated blood pressure putting strain on the heart and vessels.

Explore the essential components of the circulatory system, including the heart, blood vessels, and blood composition. This quiz will take you through the function of each part and the process of blood flow in the body. Test your understanding of how oxygen and nutrients are transported throughout the body.