Even though the amulet that Isis wears was supposed to grant its wearer "the powers of the animals and the elements," it was evident that her powers were not limited to that. She had flight, super strength, control over her molecular density (and of other objects), control the weather, stop and reverse time, and more. I think the show's writers and producers just made up powers which were convenient to use, depending on an episode's particular predicament. Still, it was an enjoyable show for a very young superhero fan during the 1970's. And I have to admit I had a huge crush on Joanna Cameron.
It's disappointing that in today's world, her superhero nomenclature has a negative connotation.