Final answer:
Stems support the plant, store food, and transport materials, but they do not absorb nutrients from the soil, which is a function of roots.
Step-by-step explanation:
The question concerns which function stems usually do not perform in vascular plants. Stems have several key roles, including supporting the aboveground parts of the plant like leaves, flowers, and buds; storing food; and facilitating the movement of materials such as water, minerals, and food between leaves and roots through their vascular systems. However, stems are generally not involved in absorbing nutrients from the soil; this function is primarily performed by the roots of the plant.