Balanoglossus possesses

Options

A. Dorsal nerve cord
B. Ventral nerve cord
C. Both 1) and 2)
D. Spinal cord

Answer

To answer the question "Balanoglossus possesses," we need to analyze the characteristics of Balanoglossus, which belongs to the phylum Hemichordata. Here’s a step-by-step breakdown:

### Step 1: Identify the Phylum
Balanoglossus is classified under the phylum Hemichordata. This is important as it helps us understand the general characteristics of the organism.

**Hint:** Remember that classification helps in understanding the anatomical features of an organism.

### Step 2: Understand the Body Structure
The body of Balanoglossus is divided into three main regions:
- **Proboscis**
- **Collar**
- **Rump**

These regions are key to its anatomy and function.

**Hint:** Focus on the body structure as it often relates to the functions of the organism.

### Step 3: Analyze the Nervous System
Balanoglossus does not possess a traditional nerve cord like higher chordates. Instead, it has a structure known as the "gut cord" or "tomocord," which is a modified version of a nerve cord.

**Hint:** Consider how the nervous system differs in non-chordates compared to chordates.

### Step 4: Identify the Presence of Notochord
In Balanoglossus, the notochord is present only in the upper part of the body. This is a key feature that distinguishes it from other organisms.

**Hint:** The notochord is a crucial feature in understanding the evolutionary biology of chordates and non-chordates.

### Step 5: Determine the Correct Answer
Based on the information gathered:
- Balanoglossus possesses both dorsal and ventral nerve cords (in the form of the gut cord).
- Therefore, the correct answer to the question is "both 1 and 2."

**Hint:** When faced with multiple-choice questions, eliminate options that do not fit the anatomical features discussed.

### Final Answer:
Balanoglossus possesses both dorsal and ventral nerve cords (in the form of the gut cord).