In which direction do roots grow? What are root hairs? What is their function?

Question

In which direction do roots grow? What are root hairs? What is their function?

Answer 1

Roots grow towards the pull of gravity.

Root hairs are modified epidermal root cells that have a hair-like extension of the cell.  Root hairs greatly increase the surface area of the root allowing more water and minerals to be absorbed from the soil particles.