An endoskeleton of calcified cartilage
Macrominerals and trace minerals.
Answer:
1.It helps to digest our food.
2.It is used as antibiotics to treat bacterial infection and disease.
3.It is used by humans to create food products such as cheese, yoghurt, pickles, soy sauce and vinegar.
4.It is use to break down our sewage and to clean up oil spills..
