I feel a little silly asking this, but if honey and sugar are biological because they are products of living things, how is air not considered biological item–would it not be considered a product of plants?
Thank you for your question. It is not all silly. You have a valid point. I was thinking of air as “atmosphere”, which existed on Earth well before living things, and therefore, “natural earth”. To be sure, plants have altered the atmosphere by providing more oxygen, but oxygen is inorganic; it did exist before life although not in as large amounts. But another argument comes into the picture.
Your question has caused me to think about it more myself, and I believe that therein is the answer. A key reason for making and putting things into categories, as pointed out in the lesson, is to help us organize and pursue our thinking regarding a topic. Here, we are having kids look at the entire world and it serves their comprehension to separate it into the categories. Of course, nature “feels” no obligation to fit neatly into our human-conceived categories.
We begin to see aspects that don’t fit clearly into the categories we have created. From this point of view, it should go here; from that point of view it should go there. Maybe there should be another category. But, would we engage in such thinking at all if we had not created the categories in the first place? In short, one may take exception with certain aspects, but this is because the process has stimulated thinking, and thinking stimulates learning.
Please ask further questions.