How does a shark differ from a teleost fish in the chemical nature of nitrogenous excretory wastes?

Explanation

**Step-by-Step Solution:**

1. **Classification of Sharks and Teleost Fish**:
- Sharks are classified as cartilaginous fish (Chondrichthyes).
- Teleost fish are classified as bony fish (Osteichthyes).

2. **Nitrogenous Waste Excretion in Sharks**:
- Sharks primarily excrete urea as their nitrogenous waste.
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