Identify the examples of homologous structures from the following-
(i) Vertebrate hearts
(ii) Thorns in Bougainvillea and tendrils of Cucurbita.
(iii) Food storage-organs in sweet potato and potato.

Explanation

To identify the examples of homologous structures from the given options, we need to understand the definition of homologous structures. Homologous structures are those that have a similar anatomical structure but may serve different functions in different organisms.

Let's analyze each option step by step:

### Step 1: Analyze Vertebrate Hearts
- **Description**: All vertebrates (mammals, birds, reptiles, amphibians, and fish) have hearts with a similar structure, typically consisting of chambers (atria and ventricles).
- **Function**: While the basic structure is similar, the function of the heart can vary among different vertebrates (e.g., fish have a two-chambered heart, while mammals have a four-chambered heart).
- **Conclusion**: Vertebrate hearts are homologous structures.
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