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Myocardium
The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x
![Cardiac muscle fibers <p>The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.CV_.H-3-1-ping.png)
Cardiac muscle fibers
The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x
![- Central nuclei <p>The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.CV_.H-3-2-ping.png)
- Central nuclei
The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x
![- Myofibrils <p>The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.CV_.H-3-3-ping.png)
- Myofibrils
The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x
![Capillaries <p>The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x</p>](https://digitalhistology.org/wp-content/uploads/2017/07/Or.CV_.H-3-4-ping.png)
Capillaries
The myocardium (black, double arrows) is the middle layer of the heart and is composed of cardiac muscle with connective tissue and blood vessels. The single nucleus of each muscle cell is centrally located, frequently surrounded by a clear space where organelles are located. In this cross section, the myofibrils can be easily distinguished. 10x, 1000x