Interesting question; answer: as a general rule, no. They are the same atoms that have existed for millenia, they are just re-routed from the air, soil, water, etc. and incorporated into "new" tissue of a new living organism. If you consider that there is some radioactive decay, e.g. carbon, then there is some change from one isotope to another, but it is the same atom until it goes from say Uranium to Lead. There is some change in molecular structure of course, as C H O P K I N S Ca Fe and trace elements recombine to form new molecular structure in the new tissue, but that's not the same as a new atom.