Problem: What is the missing first step of the following process: - Green house gases enter from the earth - Heat is trapped in atmosphere - Different things on earth are hotter - The overall planet is hotter.

A: Suns heat enters atmosphere

Problem: What is the missing first step of the following process: - Nephrons in the kidney filter the blood - The waste that is filtered out mixes with water - Become urine - Ureters carry urine out of the kidneys.

A: Blood carried into kidney by the renal artery

Problem: What is the missing first step of the following process: - The gases come to a head and push molten magma to the surface - The magma cools - With enough time the pressure builds up greatly - The resulting volcano may explode.

A: Gases cause pressure beneath the earth

Problem: What is the missing first step of the following process: - The oxygen travels to the lungs through the windpipe - The air sacs in the lungs send the oxygen into the blood stream - The carbon dioxide in the blood stream is transferred to the air sacs - The lungs expel through the nose or mouth back into the environment.

A:
You breathe oxygen into your body through the nose or mouth