Problem: Given the question: What is the missing first step of the following process:  -  Water is absorbed through roots - Chloroplast cells in leaves contain chlorophyll - Chlorophyll absorbs energy from sunlight - Energy splits water molecules into hydrogen and oxygen - Oxygen gets released into atmosphere - Hydrogen and carbon dioxide used to create glucose - Glucose is food for plants.
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The answer is:
Carbon dioxide passes through stomata in the leaves


Problem: Given the question: What is the missing first step of the following process:  -  Ocean water pulls sand off of beaches - Ocean water breaks rocks off of cliffs - Ocean water carries sand and rocks into the ocean - Sand and rocks go to other land or the bottom of the ocean.
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The answer is:
Ocean waves hit land


Problem: Given the question: What is the missing first step of the following process:  -  Blood is carried to the kidneys through the renal arteries - The kidneys contain filters inside - The filters capture the waste products - The waste is combined with water to make urine - The urine leaves the kidney and is collected in the bladder - The cleaned blood is returned to the body.
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The answer is:
