Your friend asks for your help checking their essay about sugar production and use in plants. They have found an online encyclopedia that says the following. "Plants produce glucose via photosynthesis. Glucose is linked together to form the carbohydrate starch." Your friend is confused, though, because a university website states that "glucose is linked together to form cellulose, the main part of plant cell walls."
Help your friend fact check their information. In 3 sentences, describe how they can determine which website(s) to believe.