Question

1. Identify four differences between: a. heart contractile cells and skeletal muscle fibers b. heart contractile cells and smooth muscle fibers 2. What are four similarities between: a. heart contractile cells and skeletal muscle fibers b. heart contractile cells and smooth muscle fibers

Answer 1

Differences between heart contractile cells and skeletal muscle fiber cells:

1. Heart Contractile Cells (HCM) are found in heart, responsible beating of heart, whereas skeletal muscles (SM) cells are present skeletal system of an organisms.

2. HCM cells are made up of cardiac cells and skeletal muscles cells are elongated fibres

3. HCM cells are involuntary and SM cells voluntary.

4. Single nucleus (central) found in HCM cell and several nuclei (toward peripheral) present in SM cells

5. HCM are composed of myocytes and SM cells are elongated fibers

6. Numerous mitochondria present in HCM cells and fewer in SM cells

Similarities:

1. Both are important constituent of muscle cells and made up of myofibril

2. Contractibility is similar in both cases and this is the one of their major functions

3. Striations are present in both cells (both are striated muscle cells)

4. Actin and myocin present in fiber of both muscle cells

5. Sarcolemma present in both cells

5. Action potential is common in both cells, which are responsible for muscle contraction.

Difference between contractile and smooth cells

1. HCM cells are striated but smooth cells are not
2. HCM cells are mainly present in heart and smooth cells are in wall of vital organs like intestine, stomach and bladder.
3. They are mainly present in heart where as smooth muscle cells are present reproductive system like in uterus, urinary bladder and other hollow organs.
4. Higher number of mitochondrial present in HCM as compared to smooth cells

Similarity between contractile and smooth cells

1. Both are muscles cell with actin and myosin
2. Both have contraction property
3. Both are involuntary
4. Both help in the contraction of muscles