- Air reaches the lungs - The lungs absorb the oxygen from the air - The oxygen is transported by hemoglobin - Red blood cells are made of hemoglobin - Blood has a lot of red blood cells - The heart moves the blood throughout the body - Blood can bring the oxygen to different cells in the body. What might be the first step of the process?
Ans: Air travels into the body

- Animals gain weight - The season changes to one with bad (cold, snowy) weather - Animals find a place to hibernate - Animals enter a type of 'sleep' (hibernation) - Body processes slow down - The animal's heart rate and breathing rate slow - The animal loses weight more slowly than usual - The animal is able to survive not eating or drinking without hurting itself - What might be the first step of the process?
Ans: Animals eat a lot during good (warm, clear) weather

- Sulfur in the coal combines with oxygen to form sulfur oxides - The sulfur oxides are released into the atmosphere - The sulfides combine with oxygen in the atmosphere to form sulfur trioxide - The sulfur trioxide reacts with water in the atmosphere to form sulfuric acid, a very strong acid - The sulfuric acid makes the rain acidic - What might be the first step of the process?
Ans: Coal is burned

- The oil is transported to stores - Oil is purchased by homeowners - Oil is placed into a stove in the house - The oil is lit on fire, and burns for a long time - The warm air off of the oil travels through the house - What might be the first step of the process?
Ans: Oil is gathered through mining operations