Enzymes in plants?

Question

Why are enzymes in plants not active when they are seeds, and become active when they are growing and fully grown? And is there more activity in growing plants or full grown plants?

Thank you!!

Answer 1

Not all enzymes that are present in the plant will already be present in seeds, a great number of them will be synthesized as the seed germinates, first being made from the seed reserves, later on from what the germling takes from the soil etc.  Furthermore, there's so many enzymes that it's impossible to say much about enzyme activity as a whole. The plant needs different enzymes at different stages of its growth, so particular enzymes will be synthesized more during growing (and therefore more enzyme activity), other ones more in the full grown plant. Enzymes have a turn-over rate, so they don't last forever once made. But to answer your question, you would really have to address this at an individual enzyme  basis to answer this, and you need to realize that activity is based on the amount of enzyme the plant is producing at any particular pount in time. However, on the whole I would estimate a growing plant would require more enzymes per area of tissue, and therefore enzyme activity, as its metabolic rate would be higher.

Hope this helps...