Question

1. what is the function of a mollusks shell?
2. where are spiny - skinned invertebrates found?
3. an is a part that extends out from beyond the body.
4. an arthropod has its skeleton on the of its body.
5. name three classes of arthropods.

Explanation:

1. Mollusks' shells mainly serve as a protective structure. They shield the soft - bodied mollusks from predators, physical damage, and in some cases, from desiccation (drying out).
2. Spiny - skinned invertebrates (echinoderms) are typically found in marine environments. Their unique body structures are adapted to life in the ocean, such as starfish on the ocean floor.
3. An appendage is a part that extends out from beyond the body. Examples include the legs of insects, the tentacles of squids, etc.
4. An arthropod has its skeleton on the outside of its body. This exoskeleton provides support, protection, and a surface for muscle attachment.
5. Three classes of arthropods are:

• Insecta (insects like butterflies, ants). They have three - part bodies (head, thorax, abdomen), six legs, and often wings.
• Arachnida (spiders, scorpions). They have two - part bodies (cephalothorax and abdomen), and usually eight legs.
• Crustacea (crabs, lobsters). They have a hard exoskeleton, multiple pairs of legs, and some have antennae.

Answer:

1. Protect the mollusk's soft body.
2. In marine environments.
3. appendage
4. outside
5. Insecta, Arachnida, Crustacea