Which of the following options contains a set of protochordates ?

Options

A. Balaenoptera , Macropus , Salpa
B. Delphinus , Columba , Doliolum
C. Doliolum , Ascidia , Saccoglossus
D. Salpa , Doliolum, Branchiostoma

Answer

To determine which option contains a set of protochordates, we first need to understand what protochordates are. Protochordates are a group of animals that exhibit characteristics of both invertebrates and vertebrates. They include two main subgroups: Urochordates (like tunicates) and Cephalochordates (like lancelets).

Now, let's analyze the options provided in the question step by step:

1. **Identify the options**: The question presents several organisms. We need to categorize them to see which ones belong to the protochordate group.

2. **Analyze each organism**:
- **Balenoptera (Blue Whale)**: This is a mammal, not a protochordate.
- **Macropus (Kangaroo)**: This is also a mammal, not a protochordate.
- **Sulpa**: This is a tunicate, which is a type of Urochordate, thus it is a protochordate.
- **Delphinus (Dolphin)**: This is a mammal, not a protochordate.
- **Columba (Pigeon)**: This is a bird (Aves), not a protochordate.
- **Dolioleum**: This is also a tunicate, hence it is a protochordate.
- **Acidia**: This is a type of tunicate, making it a protochordate.
- **Saccharoglossus**: This is a hemichordate, which is sometimes considered a protochordate.
- **Salpa**: This is a tunicate, thus it is a protochordate.
- **Branchiostoma**: This is a cephalochordate, making it a protochordate.

3. **Compile the protochordates**: From the analysis, the protochordates identified are:
- Sulpa (Tunicate)
- Dolioleum (Tunicate)
- Acidia (Tunicate)
- Salpa (Tunicate)
- Branchiostoma (Cephalochordate)
- Saccharoglossus (Hemichordate)

4. **Select the correct option**: The option that contains all these protochordates is the one that includes Sulpa, Dolioleum, Acidia, Salpa, and Branchiostoma.

**Conclusion**: The correct option that contains a set of protochordates is the fourth option.