Brown algae have no roots or leaves.

This statement is correct. They do not have true leaves and roots, but are attached to the substrate using rhizoids. Some types of brown algae have filled bubbles of gases (pneumatocysts), which contain photosynthetic portions of the algal thallus, floating on or near the surface of the water. The color of the species ranges from dark brown to olive, depending on the proportion of brown pigment (fucoxanthin) or green pigment (chlorophyll). Kelp is common in cold waters along continental shores.