Human Heart Structure and Functions

Structure

• The heart is a muscular organ that pumps blood throughout the body.
• It is a hollow, cone-shaped organ located in the thoracic cavity, between the lungs.
• The heart is divided into four chambers:
  1. Right atrium (receives oxygen-depleted blood from the body)
  2. Right ventricle (pumps oxygen-depleted blood to the lungs)
  3. Left atrium (receives oxygen-rich blood from the lungs)
  4. Left ventricle (pumps oxygen-rich blood to the body)

Blood Flow

• Deoxygenated blood from the body enters the right atrium.
• Blood flows from the right atrium to the right ventricle, then to the lungs to pick up oxygen.
• Oxygen-rich blood from the lungs enters the left atrium.
• Blood flows from the left atrium to the left ventricle, then to the rest of the body.

Blood Vessels

• Arteries: carry oxygen-rich blood away from the heart to the body.
• Veins: carry oxygen-depleted blood back to the heart.
• Capillaries: allow for exchange of oxygen and nutrients between blood and body tissues.

Heartbeat Regulation

• The heartbeat is regulated by the autonomic nervous system.
• The sinoatrial (SA) node, located in the right atrium, acts as the heart's natural pacemaker.
• The atrioventricular (AV) node, located between the atria and ventricles, relays signals from the SA node to the ventricles.

Functions

• The heart pumps blood throughout the body, supplying oxygen and nutrients to tissues.
• The heart regulates blood pressure and circulation.
• The heart plays a crucial role in maintaining homeostasis and overall health.