Steve, a novice gardener, plants sunflower seeds into small pots. He does not water them and is upset that they have not grown a week later. Explain why water is needed for the germination of a seed and what other conditions are required also and why

Preparation: This is a complex question requiring several strands of knowledge. It is best to break down the question into smaller chunks and answer each of those, to gain maximum marks. Firstly, knowing what germination is ? Secondly, what conditions are need for germination? Thirdly, why are these conditions required? The key part of the question also focuses specifically on water's role in germination of a starchy seed so this must be addressed too.
Answer: Germination is the growth of a embryonic plant from a seed. It requires water, heat and oxygen. If one is not available, the seed will remain dormant. Water rehydrates the cells of the seed and activates enzymes that begin producing energy for it to grow. Water causes swelling and allows for bursting of the seed coat so the plant can emerge Heat is needed for the enzyme activity, if too high or low, it decreases and slows germination Oxygen is needed for metabolism and energy for the plant to grow, until leaves can emerge and begin photosynthesis.
This answer could be extended by explaining the enzymes involved in germination e.g. gibberellin, amylase