A microspecimen of heart shows rectangular cells from 50 to 120 micrometers large with central position of nucleus and developed myofibrils. The cells are connected by intercalated discs. These cells are responsible for the following function:

Answer options

1. Endocrine
2. Function of impulse conduction
3. Function of heart contractions
4. Regeneratory
5. Protective

Explanation

Heart muscles are composed of tubular cells called myocytes, and a myofibril is the basic unit of the myocyte. Notice the size of the cells and the intercalated discs (smooth muscles).