Heart and Circulatory System Overview

Aug 12, 2024

Understanding the Human Heart and Circulatory System

Key Functions of the Heart

  • Beats approximately 100,000 times per day
  • Pumps 2,000 gallons of blood daily
  • Maintains blood flow through 60,000 miles of blood vessels

Components of Blood Vessels

  • Arteries: Carry oxygen-rich blood from the heart to the body
  • Veins: Carry deoxygenated blood back to the heart
  • Capillaries: Small blood vessels where exchange of substances occurs

Structure of the Heart

  • Chambers: Four chambers - right atrium, left atrium, right ventricle, left ventricle
  • Valves: Four one-way valves - tricuspid valve, mitral valve, aortic valve, pulmonic valve

Blood Circulation Process

Oxygenation in the Lungs

  • Blood becomes oxygen-rich in the lungs

Left Side of the Heart

  1. Oxygenated blood returns to the left atrium via pulmonary veins
  2. Blood flows into the left ventricle through the mitral valve
  3. Blood is pumped into the aorta, and then to the rest of the body

Blood Flow to Organs and Tissues

  • Oxygenated blood travels through arteries and capillaries to organs and tissues
  • Blood becomes deoxygenated in the capillaries

Return to the Heart

  1. Deoxygenated blood is carried back to the heart by veins
  2. Veins form larger vessels known as the vena cava
  3. Blood enters the right atrium
  4. Blood flows into the right ventricle via the tricuspid valve
  5. Blood is pumped into the pulmonary artery

Reoxygenation in the Lungs

  • Deoxygenated blood is oxygenated in the lungs and returns to the left atrium via the pulmonary vein
  • The cycle repeats