Question

Neurogenic heart is the characteristic of
A) Humans
B) Lower Invertebrates
C) Rat
D) Rabbit

Answer 1

Hint: In neurogenic heart, the nerve from the brain initiates cardiac movement. In myogenic heart the muscles present in the heart initiates cardiac movement.

Complete answer :
To answer this question, we must know the types of heart and the mechanism of their functioning.
Mainly there are two types of heart neurogenic and myogenic heart. In the neurogenic heart, the initiation of heart beat is under the control of nerves initiating from the brain. Whereas in myogenic heart, the heartbeat is initiated by specialised muscle fibres present in the heart.
Myogenic heart is found in vertebrates. This kind of heart is called a human heart which can beat of its own and doesn’t need any external impulse. The impulse is generated by a pacemaker present inside the heart. The contraction of heart muscles regulates the flow of blood. The circulatory system is of closed type with 2, 3, 4 chambered heart and blood flows through the vessels. This kind of heart is present in rats, rabbits, humans and other mammals.

Neurogenic heart is found in lower invertebrates like annelids and arthropods. The heartbeat is initiated by the ganglion situated near the heart. The impulse for contraction is generated by the nervous system. They have a sac like heart and blood do not flow through the vessels hence the circulatory system is of open type.

Thus, the correct answer is (B) lower invertebrates. Neurogenic heart is the characteristic feature of lower invertebrates.

Note:Neurogenic heart stops beating immediately after removal from the body hence transplantation is not possible whereas myogenic heart continues to beat for some time. Hence heart transplantation is possible.