1. The "what" or "how" part: This identifies the phenomenon or process being investigated. It asks about the nature or behavior of something.

* Example: "What is the effect of fertilizer on plant growth?"

2. The "why" or "under what conditions" part: This sets the context and specifies the variables or factors that will be explored. It explains the purpose of the investigation and the specific aspects being studied.

* Example: "What is the effect of different types of fertilizer on the height of tomato plants grown in a controlled environment?"

By combining these two parts, a science question becomes focused and specific, leading to a meaningful and testable investigation.