In stems which vascular tissue is on the insdie of the bundle

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

Nerve cells are specialized to respond to stimulitrue or false?

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.