Or not alive, but fossilized. Speculation gets us nowhere - unless you happen to construct outside alternative life with modern nanotechnology and chemistry, it is bootless to even argue for other forms.
The closest we got is with Threose Nucleic Acids. Managed to get a working hemoglobin binder with this. But it is a relatively obvious analog.
The closest we got is with Threose Nucleic Acids. Managed to get a working hemoglobin binder with this. But it is a relatively obvious analog.