An "extra skeleton" isn't a standard biological term, but the closest concept is an exoskeleton, which is an external, hard covering that provides support and protection to an animal's body.
Understanding Exoskeletons
-
Definition: An exoskeleton is a rigid outer covering that protects the internal organs and provides structural support. The term literally means "outside skeleton."
-
Who Has Them?: Many invertebrates, animals without backbones, possess exoskeletons.
-
Examples:
- Insects: A prime example is insects. Their exoskeletons are made of chitin, a tough polysaccharide.
- Crustaceans: Crabs, lobsters, and shrimp also have exoskeletons, often reinforced with calcium carbonate.
- Arachnids: Spiders and scorpions utilize exoskeletons.
Functions of Exoskeletons
- Protection: Exoskeletons offer protection from predators and physical damage.
- Support: They provide structural support, enabling movement and maintaining body shape.
- Water Retention: Exoskeletons can help prevent water loss in terrestrial invertebrates.
Molting
As the animal grows, it must shed its exoskeleton in a process called molting. A new, larger exoskeleton grows underneath the old one. This process leaves the animal vulnerable until the new exoskeleton hardens.
Therefore, while "extra skeleton" isn't technically accurate, it most likely refers to an exoskeleton, a protective outer covering found in many invertebrates.
