Dark colour of breast muscles of birds of flight is due to high concentration of

Options

A. Mitochondria
B. Haemoglobin
C. Myoglobin
D. Both myoglobin and mitochondria.

Answer

To solve the question regarding the dark color of breast muscles in birds of flight, we can follow these steps:

### Step 1: Understand the Question
The question asks why the breast muscles of flying birds are dark in color.

### Step 2: Identify the Key Components
The options provided are:
- A) Mitochondria
- B) Hemoglobin
- C) Myoglobin
- D) Both myoglobin and mitochondria

### Step 3: Analyze the Options
- **Mitochondria**: These organelles are responsible for energy production in cells. While they are abundant in the breast muscles of flying birds to support high energy demands, they do not contribute to the color of the muscles.

- **Hemoglobin**: This is the oxygen-carrying pigment found in red blood cells, not in muscle tissue. Therefore, it is not responsible for the color of the breast muscles.

- **Myoglobin**: This is an oxygen-carrying protein found in muscle tissue. It has a reddish color and is present in high concentrations in the breast muscles of birds that fly, contributing to their dark appearance.

- **Both myoglobin and mitochondria**: While both are present, only myoglobin is responsible for the dark coloration.

### Step 4: Conclusion
The dark color of the breast muscles in birds of flight is primarily due to the high concentration of **myoglobin**. Therefore, the correct answer is option C: Myoglobin.

### Final Answer
The dark color of breast muscles of birds of flight is due to a high concentration of **myoglobin**.

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