Dugesia possess a central tubular digestive tract and this has three branches. These branches consist of ceca, which deliver nutrients to the body.
Can you include the following substitutions??
1) They provide ecologically and economically indispensable goods.
2) They provide nesting and feeding habitats for aquatic plants and animals.
3) They maintain healthy ocean environments
4) They remove pollutants from rivers and streams
Answer:
algae are autotrophic
Explanation:
the cell wall is made up of cellulose
