instruction:
Generate an overlapping word between the given two sentences. When you find the overlapping words, they don't have to match exactly, e.g., "survival" and "survive" are valid overlapping words. Little words like "the" or "of" don't count! You must generate significant words which are not the stop words.
question:
Sentence1: Mitosis is cell division. 
Sentence2: mitosis often causes growth.
answer:
Mitosis


question:
Sentence1: Water is essential for all life on Earth. 
Sentence2: H2O is needed for all life on Eartth.
answer:
Earth


question:
Sentence1: Scientists have shown that ocean organisms known as zooplankton harbor cholera bacteria. 
Sentence2: Tiny ocean organisms feed on phytoplankton.
answer:

ocean