Crystalline silica is a natural compound in the earth's crust and is a basic component of sand and granite. Silicosis is an incurable disease of the lungs caused by breathing crystalline silica dust. This dust can cause scar tissue to form in the lungs.
Many cells working together forms a tissue. Many tissues working together forms organs. Many organs working together forms organ systems. So it goes from general to most specific. Organ systems are needed in order for life. This proves that cells are the most basic units of life.
It is logical because the balloon lets the student see how much gas is released in the reaction. the balloon inflates with invisible air the student will normally not see.
