yaya and bre's hair on next top model

[BeautifulRoots]

I must say yaya and bre from next top model have really pretty hair. Whenever the re-runs of next top model come on and they are on the show, I am just in awe of their hair. I was wondering, does anyone know if their hair is all natural, or are they texlaxed or something? And does anyone know how to achieve the styles they have on the show. (Not the modeling hair styles, just the styes while lounging around the house, or doing go-see's and such.)