‘What are Mollusks?’
‘What are Mollusks?’ by Sarah Machajewski
1. A mollusk is a kind of animal with a soft body. Most mollusks have a hard shell that protects their body, but not all do. Scientists think they account for 23% of all known sea animals.
2. Mollusks are invertebrates, which do not have a backbone. Their bodies are not divided into sections.
3. Gastropods are the largest group of mollusks. They include snails, slugs and sea slugs. Most gastropods have one shell. The shells are commonly coiled and can have beautiful colours and patterns. Slugs do not have a shell.
4. Gastropods have a complete digestive system and highly developed sense organs. On land, snails and slugs release slime from their body, which they glide over as they move.
5. Gastropods feed using the ‘radula’. Radula is covered with rows of tiny teeth. They use the tiny teeth for grinding food and scraping it off surfaces.
6. Bivalves (e.g. clams, oysters, mussels, scallops) filter sediments out of the water as they eat. One adult oyster can filter about 190L of water a day. They make the water clean and clear — — a healthy home for other marine creatures.
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