Through the heart is an involuntary organ, the fibres are different from smooth muscles in possessing

Options

A. striations
B. tendons
C. mitochondria
D. sarcoplasm

Answer

To answer the question regarding the differences between heart muscle fibers and smooth muscle fibers, we can break it down step by step:

### Step-by-Step Solution:

1. **Understanding the Heart as an Involuntary Organ**:
- The heart is classified as an involuntary organ, meaning its functions are not consciously controlled by an individual. It operates automatically to pump blood throughout the body.

2. **Identifying Muscle Types**:
- The heart is composed of cardiac muscle, which is a type of involuntary muscle. On the other hand, smooth muscle is also an involuntary muscle but is found in various organs such as the intestines and blood vessels.

3. **Comparing Cardiac Muscle and Smooth Muscle**:
- Both cardiac and smooth muscles are involuntary, but they have distinct structural differences.
- Cardiac muscle fibers are striated, meaning they have a banded appearance due to the arrangement of actin and myosin filaments.
- Smooth muscle fibers, in contrast, do not have striations; they appear smooth under a microscope.

4. **Analyzing the Options**:
- The options provided were:
- a) Striation
- b) Tendons
- c) Mitochondria
- d) Sarcoplasm
- Among these, the presence of striations is a key distinguishing feature of cardiac muscle compared to smooth muscle.

5. **Conclusion**:
- Therefore, the correct answer to the question is that cardiac muscle fibers differ from smooth muscle fibers by possessing striations.

### Final Answer:
The fibers of the heart (cardiac muscle) are different from smooth muscles in possessing **striations**.