Problem: What is the missing first step of the following process: - Food begins to be processed by the digestive system - The pancreas releases enzymes to aid digestion - Digested food affects the amount of sugar in the blood - The pancreas releases one hormone to lower the blood sugar (glucose) level - The pancreas releases another hormone to raisethe blood sugar (glucose) level.

A: Food enters the body

Problem: What is the missing first step of the following process: - The particles remove small pieces of the rock each time they touch the rocks - The particles continue to hit, brush against, or grow against the rocks - The rock eventually is broken apart by this contact - The pieces of the rock are now small rocks - The rock pieces are worn away into smaller and smaller pieces by the same forces -

A: Particles in the environment interact with rocks

Problem: What is the missing first step of the following process: - The aluminum is collected - Taken to a treatment plant - The aluminum is sorted and cleaned ready for reprocessing - The aluminum is re-melted - Turned into molten aluminum - The aluminum is made into large blocks called ingots - The ingots are sent to mills to be rolled out - The rolled out product is made into new aluminum products.

A: The consumer throws aluminum cans and foil into a recycle bin

Problem: What is the missing first step of the following process: - The energy causes the fault lines give way - The earth's plates move - The energy radiates outward from the fault in all directions - The seismic waves shake the earth as they move through it.

A:
Energy builds up in the crust of the earth