Heart Physiology - Reptiles

Introduction

• Reptiles, a diverse group of animals including snakes, lizards, and turtles, exhibit a unique heart physiology.
• Their circulatory system differs from both mammals and birds.

The Reptilian Heart

• Reptiles generally possess a three-chambered heart consisting of:
  • Two atria.
  • One partially divided ventricle.
• The ventricle is not completely separated, leading to some mixing of oxygenated and deoxygenated blood.

Crocodile Exception

• An exception to the reptilian heart structure is found in crocodiles.
• Crocodiles have a four-chambered heart, similar to that of mammals and birds.
• In crocodiles, the ventricles are completely separated, preventing significant mixing of blood.

Physiological Implications

• The reptilian heart structure results in less efficient separation of oxygenated and deoxygenated blood.
• This limits their ability to support high metabolic rates seen in mammals and birds.

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Biology

Heart Physiology - Reptiles

Summary for Reptiles

• Reptiles typically possess a three-chambered heart with two atria and one partially divided ventricle.
• Crocodiles, however, have a four-chambered heart similar to mammals and birds.