Explain the general characters of phylum Arthropoda. Give one example of following classes
(i) Crustacea, (ii) Myriapoda, (iii) insecta, (iv) Arachnida.

Explanation

### Step-by-Step Solution:

1. **Introduction to Phylum Arthropoda**:
- Phylum Arthropoda is the largest phylum in the animal kingdom, comprising a diverse group of organisms including insects, arachnids, myriapods, and crustaceans.

2. **General Characteristics of Phylum Arthropoda**:
- **Triploblastic**: Arthropods have three germ layers - ectoderm, mesoderm, and endoderm.
- **Bilateral Symmetry**: Their body plan is symmetrical along a central axis, meaning the left and right sides are mirror images.
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