MUSCLE PHYSIOLOGY

Detailed explanation-1: -Cardiac muscle cells (cardiomyocytes) are striated, branched, contain many mitochondria, and are under involuntary control. Each myocyte contains a single, centrally located nucleus and is surrounded by a cell membrane known as the sarcolemma.

Detailed explanation-2: -Only cardiac muscle tissue, comprising cells called myocytes, is present in the heart.

Detailed explanation-3: -There are two major types of cardiac muscle cells: myocardial contractile cells and myocardial conducting cells. The myocardial contractile cells constitute the bulk (99 percent) of the cells in the atria and ventricles.

Detailed explanation-4: -Cardiomyocytes contain many sarcosomes, which provide the required energy for contraction. Unlike skeletal muscle cells, cardiomyocytes normally contain a single nucleus. Cardiomyocytes generally contain the same cell organelles as skeletal muscle cells, although they contain more sarcosomes.