Give a comparative account of heart in vertebrates with the help of diagrams only (no description in required). (IFS 2023/15 Marks)

Introduction:

The heart is a vital organ in vertebrates that pumps blood throughout the body. While the basic function of the heart remains the same across all vertebrates, there are some differences in the structure and function of the heart in different species.

Comparative Account of Heart in Vertebrates

1. Pisces (Fishes)

• Structure: Two-chambered heart (1 atrium, 1 ventricle).
• Circulation: Single circulation (blood passes through the heart once per complete cycle).

2. Amphibians

• Structure: Three-chambered heart (2 atria, 1 ventricle).
• Circulation: Double circulation (incomplete; mixing of oxygenated and deoxygenated blood occurs).

3. Reptiles

• Structure: Three-chambered heart (2 atria, 1 ventricle with partial septum in some species like lizards).
• Circulation: Double circulation (partial separation reduces mixing of blood).

4. Aves (Birds)

• Structure: Four-chambered heart (2 atria, 2 ventricles).
• Circulation: Double circulation (complete separation of oxygenated and deoxygenated blood).

5. Mammals

• Structure: Four-chambered heart (2 atria, 2 ventricles).
• Circulation: Double circulation (complete; highly efficient for metabolism).

Conclusion:

While the basic function of the heart remains the same in all vertebrates, there are differences in the structure and efficiency of the heart across different species. These differences reflect the evolutionary adaptations of vertebrates to their environments and lifestyles.