What are the characteristics of cardiac muscle cells?

Cardiac muscle cells are one of three types of muscle cells found in the body. They are cylindrical, branched, slightly striated, and uninucleated. These muscle cells are found only in the heart and are responsible for the contraction and relaxation of the heart, which pumps blood throughout the body. Cardiac muscle cells have four main characteristics that facilitate their functioning: 

1. Rhythmicity refers to the ability of cardiac muscle cells to spontaneously depolarize and generate rhythmic impulses, independent of any external electrical signals from the nervous system. The rhythmic impulses that are generated trigger coordinated contractions of the heart, allowing it to pump blood throughout the body in a steady, consistent manner. Rhythmicity is also known as automaticity or pacemaker ability of cardiac muscle cells. 
2. Excitability in cardiac muscle cells refers to their ability to respond to adequate stimuli or electrical impulses by generating an action potential. This property allows cardiac muscle cells to contract in a coordinated manner, contributing to the regular pumping action of the heart. 
3. Contractility refers to the ability of cardiac muscle cells to contract or shorten and generate force when stimulated by electrical signals. The contractility of cardiac muscle cells is essential for the heart to pump blood effectively throughout the body. The pumping power of the heart is determined by the strength of myocardial contraction. 
4. Conductivity in cardiac muscle cells refers to their ability to transmit cardiac impulses from one cell to another. This characteristic enables the coordinated transmission of electrical impulses through the heart, resulting in the efficient pumping of blood via synchronized contractions.