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.

Q: Sentence1: Heterotrophs are living things that cannot make their own food. 
Sentence2: food contains organic molecules.

A: food
****
Q: Sentence1: To keep cut flowers lasting longer, use a commercial florist preservative such as Floralife. 
Sentence2: Dehydrating food is used to make it last longer.

A: lasting
****
Q: Sentence1: Sperm and eggs are cells known as gametes. 
Sentence2: Fertilization occurs when gametes fuse.

A:
gametes
****