I think it's the Pancreas
Radiometric dating reveals the exact (i think its exact) age of a fossil.
The Gecko. While human-made devices inspired by gecko feet have emerged in recent years, enabling their wearers to slowly scale a glass wall, the possible applications of gecko-adhesion technology go far beyond Spiderman-esque antics. A researcher is looking into how the technology could be applied in a high-precision industrial setting, such as in robot arms used in manufacturing computer chips.
The Rules of Protein Structure. The function of a protein is determined by its shape. The shape of a protein is determined by its primary structure (sequence of amino acids). The sequence of amino acids in a protein is determined by the sequence of nucleotides in the gene (DNA) encoding it.
D) It can only be used in areas with specific kinds of rivers.