The spinal cord is made up of the pons and the medulla.
the brain and the brain stem.
white and gray matter.
gray matter only.

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

Select the word from the list that best fits the definition a system made of 25 satellites

All organisms contribute some water to the water cycle by conducting