Which one of the following is correct location of the type of muscle present in that body part

Options

A. Iris – Involuntary smooth muscle
B. Heart wall – Involuntary unstriated muscle
C. Biceps of upper arm – smooth muscle fibres
D. Abdominal wall – smooth muscle

Answer

To solve the question regarding the correct location of the type of muscle present in specific body parts, we will analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Analyze the First Option: Iris**
- The iris is part of the eye and is responsible for regulating the amount of light entering the pupil.
- The muscles in the iris are smooth muscles and are involuntary, meaning they are not under conscious control.
- **Conclusion**: This option is correct as the iris contains involuntary smooth muscle.

2. **Analyze the Second Option: Heart Wall**
- The heart wall is primarily made up of cardiac muscle.
- Cardiac muscles are striated (having stripes) and are also involuntary.
- However, they are distinct from smooth muscles.
- **Conclusion**: This option is incorrect because the heart wall contains cardiac muscle, not smooth muscle.

3. **Analyze the Third Option: Biceps of the Upper Arm**
- The biceps muscle is a skeletal muscle, which is striated and under voluntary control.
- Skeletal muscles are not smooth muscles; they are responsible for voluntary movements.
- **Conclusion**: This option is incorrect as the biceps contain striated skeletal muscle, not smooth muscle.

4. **Analyze the Fourth Option: Abdominal Wall**
- The abdominal wall consists of smooth muscles, which are involuntary and help in peristalsis (the movement of food through the digestive tract).
- The abdominal wall is considered part of the viscera, which contains smooth muscle.
- **Conclusion**: This option is correct as the abdominal wall contains smooth muscle.

### Final Answer:
The correct options are:
- **Option 1**: Iris has involuntary smooth muscle.
- **Option 4**: Abdominal wall has smooth muscle.