How many contraction nodes are found in heart of Human :-a)Oneb)Twoc)Manyd)NoneCorrect answer is option 'B'. Can you explain this answer?

Question

Answer

Two contraction nodes...SAN and AVN..option B

Answer

SAnode and AV nodes

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SAN(pacemaker), AVN(Pace setter).. are two contraction nodes found in heart...

Answer

Option B is correct, A. v and S. A nodes are present..

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Sino atrial node nd Atrioventricular node. hence option B is correct.

Answer

AV node and SA node

Answer

A node is a specialized type of tissue that behaves as both muscle and nervous tissue. There are 2 nodes present in the human heart. SA node and AV node.

The sinoatrial node, also referred to as the pacemaker of the heart, coordinates heart contractions. Located in the upper wall of the right atrium, it generates nerve impulses that travel throughout the heart wall causing both atria to contract.

The atrioventricular node lies on the right side of the partition that divides the atria, near the bottom of the right atrium. When the impulses generated by the SA node reach the AV node, they are delayed for about a tenth of a second. This delay allows the atria to contract, thereby emptying blood into the ventricles. The AV node then sends the impulses down the atrioventricular bundle. This bundle of fibers branches off into two bundles and the impulses are carried down the center of the heart to the left and right ventricles.

Hence, the correct answer is option B.

Answer

Two contraction nodes are found in the heart of humans..... SA node and AV node

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There are 2 contraction nodes - 1. SA node and AV node...so answer is 2...

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Correct answer is option'B'

Answer

Contraction Nodes in the Human Heart

The human heart is a complex organ responsible for pumping blood throughout the body. It consists of several specialized structures that work together to ensure efficient and coordinated contractions. One of these structures is the contraction node, which plays a crucial role in regulating the heart's rhythm.

The Contraction Nodes

There are two main contraction nodes in the human heart: the sinoatrial (SA) node and the atrioventricular (AV) node. These nodes are specialized groups of cells that generate electrical signals, initiating the contraction of the heart muscle.

1. Sinoatrial (SA) Node: The SA node, also known as the pacemaker of the heart, is located in the upper part of the right atrium. It generates electrical impulses that spread through the atria, causing them to contract and pump blood into the ventricles. The SA node sets the heart's rhythm and determines the heart rate.

2. Atrioventricular (AV) Node: The AV node is situated between the atria and the ventricles, near the center of the heart. It receives the electrical signals from the SA node and delays their transmission to the ventricles. This delay allows the atria to fully contract and empty their contents into the ventricles before they contract. Once the electrical impulses reach the AV node, they are conducted to the ventricles via specialized pathways called the bundle of His and Purkinje fibers, resulting in ventricular contractions.

The Role of Contraction Nodes

The contraction nodes in the human heart serve several important functions:

1. Initiating the Heartbeat: The SA node generates electrical impulses that initiate the contraction of the heart muscle, starting the heartbeat.

2. Regulating Heart Rate: The SA node sets the heart's rhythm and determines the heart rate. Under normal circumstances, the SA node controls the heart rate, ensuring it is appropriate for the body's needs.

3. Coordinating Atrial and Ventricular Contractions: The AV node acts as a gatekeeper, receiving electrical signals from the atria and delaying their transmission to the ventricles. This delay allows for synchronized contractions and efficient pumping of blood.

Conclusion

In summary, the human heart contains two contraction nodes: the SA node and the AV node. These specialized structures play a vital role in initiating and coordinating the contractions of the heart muscle, ensuring efficient blood circulation throughout the body. Therefore, the correct answer to the question is option 'B' - Two.

Answer

A node is a specialized type of tissue that behaves as both muscle and nervous tissue. There are 2 nodes present in the human heart. SA node and AV node.
The sinoatrial node, also referred to as the pacemaker of the heart, coordinates heart contractions. Located in the upper wall of the right atrium, it generates nerve impulses that travel throughout the heart wall causing both atria to contract.
The atrioventricular node lies on the right side of the partition that divides the atria, near the bottom of the right atrium. When the impulses generated by the SA node reach the AV node, they are delayed for about a tenth of a second. This delay allows the atria to contract, thereby emptying blood into the ventricles. The AV node then sends the impulses down the atrioventricular bundle. This bundle of fibers branches off into two bundles and the impulses are carried down the center of the heart to the left and right ventricles.
Hence, the correct answer is option B.

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