In arthropoda, respiration is accomplished by

Options

A. Book lungs and gills
B. Tracheae, book lungs and gills
C. Tracheae only
D. Tracheae in terrestrial habitat and gills in aquatic habitats.

Answer

**Step-by-Step Solution:**

1. **Understanding Arthropoda**: Arthropoda is a phylum that includes animals with jointed legs and appendages. This phylum encompasses a wide variety of organisms such as insects, arachnids, and crustaceans.

2. **Identifying Respiratory Structures**: In arthropods, respiration can occur through different structures depending on their habitat:
- **Tracheae**: These are tube-like structures that transport air directly to the tissues. They are primarily found in terrestrial arthropods, especially insects.
- **Book lungs**: These are specialized respiratory structures found in some terrestrial arthropods, such as scorpions. They consist of stacked, leaf-like structures that facilitate gas exchange.
- **Gills**: These are used by aquatic arthropods, such as prawns and crabs, to extract oxygen from water.

3. **Analyzing the Options**:
- **Option 1**: Book lungs and gills - This option is incomplete as it does not include tracheae.
- **Option 2**: Tracheae, book lungs, and gills - This option correctly includes all three types of respiratory structures found in arthropods.
- **Option 3**: Tracheae only - This option is too limited as it excludes book lungs and gills.
- **Option 4**: Tracheae in terrestrial habitat and gills in aquatic habitat - While this option mentions two types, it omits book lungs.

4. **Conclusion**: The most comprehensive and correct answer is **Option 2: Tracheae, book lungs, and gills**, as it encompasses all the respiratory structures utilized by arthropods in different environments.

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