Final answer:
When you pick a mushroom, you only remove the fruiting body and the main fungal body, called the mycelium, remains underground.
Step-by-step explanation:
When you pick a mushroom, you are only removing the fruiting body or the reproductive stage of the fungus. This is the visible part that we commonly see. The main body of the fungus, called the mycelium, remains hidden underground or within the substratum. The mycelium consists of a network of slender thread-like structures called hyphae, which make up the vegetative stage of the fungus. The mycelium is responsible for absorbing nutrients and decomposing organic matter.