Which of the following structures is homologus to the wing of a bird?

Options

A. Flipper of Whale
B. Dorsal fin of a Shark
C. Wing of a Moth
D. Hind limb of Rabbit.

Answer

To determine which structure is homologous to the wing of a bird, we need to understand the concept of homologous organs. Homologous organs are those that share a similar structure, anatomy, and genetic makeup, but may serve different functions in different species.

**Step 1: Define Homologous Structures**
- Homologous structures are similar in morphology, anatomy, and genetics, but differ in their functions.

**Step 2: Analyze the Options**
- The options provided are:
1. Flipper of a whale
2. Dorsal fin of a shark
3. Wing of a moth
4. Hind limb of a rabbit

**Step 3: Compare Each Option to the Wing of a Bird**
- **Flipper of a whale**: Both the wing of a bird and the flipper of a whale are used for movement in their respective environments (flying and swimming), but they share a similar bone structure (humerus, radius, and ulna). Thus, they are homologous.
- **Dorsal fin of a shark**: This structure is not homologous to the wing of a bird as it does not share a similar bone structure; it is more related to stabilization in water.
- **Wing of a moth**: This structure is analogous, not homologous, as it serves a similar function (flying) but has a different structural makeup.
- **Hind limb of a rabbit**: While this limb is homologous to the wing of a bird in terms of bone structure, it serves a different function (walking/running).

**Step 4: Identify the Correct Answer**
- The flipper of a whale is the best example of a homologous structure to the wing of a bird, as both share a similar anatomical structure but perform different functions.

**Conclusion**
- Therefore, the homologous structure to the wing of a bird is the **flipper of a whale** (Option A).

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