The key difference between myogenic and neurogenic heart is that in myogenic heart, the beating rhythm is set by specialized muscle cells, while in neurogenic heart, the beating rhythm is set through nerve impulses.
Myogenic and neurogenic hearts are two types of hearts found in animals. Myogenic hearts can be seen in animals with a closed circulatory system. Neurogenic hearts can be seen in animals with an open circulatory system. A myogenic heart beats due to specialized muscles cells within the heart while a neurogenic heart beats due to nerve impulses.
CONTENTS
1. Overview and Key Difference
2. What is a Myogenic Heart
3. What is a Neurogenic Heart
4. Similarities Between Myogenic and Neurogenic Heart
5. Side by Side Comparison – Myogenic vs Neurogenic Heart in Tabular Form
6. Summary
What is Myogenic Heart?
A myogenic heart is a heart in which the beating rhythm is set by specialized muscle cells within the heart. Some invertebrates and all vertebrates have a myogenic heart. Structurally, a myogenic heart has 2 or 3 or 4 chambers separated by muscles. Animals that have a closed circulatory system have myogenic hearts.
Figure 01: Myogenic Heart
A myogenic heart beats for some time even after the removal from the body. Hence, heart transplantation can be done for myogenic hearts. A myogenic heart is independent of the nervous input.
What is Neurogenic Heart?
Some animals, such as annelids and most arthropods, have an open circulatory system. In those animals, the heart is sac-like or tubular. The beating rhythm is created by nerve impulses. Hence, the heart is known as the neurogenic heart. A neurogenic heart acts as a suction pump. It relaxes and contracts. When the heart relaxes, it creates a vacuum and sucks blood into the heart.
Figure 02: Closed and Open Circulatory Systems
When a neurogenic heart is removed from the body, it stops beating immediately. Hence, heart transplantation cannot be done for neurogenic hearts. The neurogenic heart is dependent on the nervous input.
What are the Similarities Between Myogenic and Neurogenic Heart?
- Animals have myogenic and neurogenic hearts.
- Most invertebrates have a neurogenic heart, while some invertebrates such as molluscs have a myogenic heart.
What is the Difference Between Myogenic and Neurogenic Heart?
The myogenic heart is a heart that beats by specialized muscle cells, while a neurogenic heart is a heart that beats by nerve impulses. So, this is the key difference between myogenic and neurogenic heart. Furthermore, the myogenic heart works as a pressure pump, while the neurogenic heart acts as a suction pump. Moreover, the myogenic heart is a part of the closed circulatory system, while the neurogenic heart is a part of an open circulatory system. Thus, this is also a significant difference between myogenic and neurogenic heart.
Some invertebrates (mollusc) and all vertebrates have a myogenic heart, while invertebrates such as Annelids and most arthropods have a neurogenic heart. Besides, structurally, a myogenic heart has 2, 3 or 4 chambers. In contrast, a neurogenic heart is sac-like or tubular. Therefore, this is the structural difference between myogenic and neurogenic heart. Most importantly, the myogenic heart continues to beat for some time even after the removal from the body. But neurogenic heart stops beating immediately when removed from the body. Hence, this is also a major difference between myogenic and neurogenic heart.
Below is a summary of the difference between myogenic and neurogenic heart in tabular form.
Summary – Myogenic vs Neurogenic Heart
The myogenic heart is a part of the closed circulatory system possessed by some invertebrates and all vertebrates. Meanwhile, the neurogenic heart is a part of the open circulatory system possessed by invertebrates. Beating rhythm is set by specialized muscle cells in the myogenic heart. The beating rhythm of the neurogenic heart is set by nerve impulses. Thus, this summarizes the difference between myogenic and neurogenic heart.
Reference:
1. “Neurogenic Contraction.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., Available here.
2. “Myogenic Mechanism.” Wikipedia, Wikimedia Foundation, 12 Dec. 2020, Available here.
Image Courtesy:
1. “Diagram of the human heart (cropped)” By Wapcaplet – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Figure 40 01 01ab” By CNX OpenStax – (CC BY 4.0) via Commons Wikimedia
Leave a Reply