sentences:  Modern bryophytes either avoid it or give in to it, restricting their ranges to moist settings, or drying out and putting their metabolism "on hold" until more water arrives, as in the liverwort genus "Targionia".Tracheophytes resist desiccation, by controlling the rate of water loss.They all bear a waterproof outer cuticle layer wherever they are exposed to air (as do some bryophytes), to reduce water loss, but since a total covering would cut them off from in the atmosphere tracheophytes use variable openings, the stomata, to regulate the rate of gas exchange.