Biology · No topic
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Which of the following layer is mainly composed of cardiac muscles?
- A
Endocardium
- B
Epicardium
- C
Pericardium
- D
Myocardium
The correct answer is Myocardium because it is the layer primarily made up of cardiac muscle, enabling the heart to contract and pump blood effectively. The other options, while associated with the heart, do not contain cardiac muscle:
- Endocardium: This is the innermost layer that lines the heart chambers and valves, but it does not consist of muscle tissue.
- Epicardium: The outer layer that provides protection but is made up of connective tissue.
- Pericardium: The fibrous sac surrounding the heart that provides a protective layer but is not muscular.
Thus, the myocardium is the only layer that fulfills the requirement of being composed of cardiac muscles.
The endocardium is the innermost layer of the heart, lining the chambers and valves. While it plays a crucial role in heart function, it is not composed of cardiac muscle.
The epicardium is the outer layer of the heart, serving as a protective layer. It does not consist of cardiac muscle tissue but rather a layer of connective tissue and fat.
The pericardium is a fibrous sac that surrounds the heart, providing protection and support. It is not a muscular layer and does not contain cardiac muscle.
The myocardium is the thick middle layer of the heart wall and is primarily composed of cardiac muscle. This layer is responsible for the heart's contraction and pumping blood throughout the body.
Tagged under Biology · No topic · 2025