How does the water from the soil reach every part of the plant?

Root hairs participate in the intake of water. They absorb water from the intervening spaces between the soil particles. by a process of osmosis and active transport, water is drawn inside. The water moves from cell to cell and enters into the vascular tissue. There a force is produced which pushes water up from the roots. This  is called root pressure. The water from the  stems now enters the leaves. This is known as the transpiration stream.