Root genetics research. Roots of the Thale cress plant, Arabidopsis thaliana, growing in a culture medium. The roots have fine root hairs growing horizontally out of them. Root hairs are tubular projections from absorptive cells within the root. The hairs help to anchor the plant within the soil and absorb water and nutrients. A. thaliana is mainly used as an international plant standard for genetic research. This is because of its short generation time, high seed production, small genome (genetic sequence) and ease of genetic manipulation. Research into A. thaliana is vital for improving our understanding of crop plants.