Does a living organ have to have a nervous system

Check all that apply diatoms are marine algae that have a shell made of silica, what are some of the uses of the silica shell after the diatoms die? 1.the shells make up the diatomaceous earth used in filters 2.it can be used as an ingredient in abrasives 3.they are used in food products 4.the shells can be used in some insulating materials

Describe how a student should adjust the microscope to see the cells on a slide more clearly?

How many types of rock can form from the rock cycle