I am a passionate reader, having been tutored very early by my mother. I avidly devoured all books on chemistry that I could find. Formal chemistry at school seemed boring by comparison, and my performance was routine. In contrast, I did spectacularly well in mathematics and sailed through classes and exams with ease.

Hard as it is to imagine, there's a move afoot in Congress to take away the public's free online access to tax-funded medical research findings. That would be bad for medical discovery, bad for patients looking for the latest research results, and another rip-off of the American taxpayer.

One always has to worry when capitalism has a role in health care. If you're just using health care to make money, you will treat the wrong diseases. Capitalism has its limits. There is a role for governments, and this is one where they should be involved.

During normal cell metabolism, RNA is constantly being made and broken down. The purine and pyrimidine residues are reused by several salvage pathways to make more genetic material. Purine is salvaged in the form of the corresponding nucleotide, whereas pyrimidine is salvaged as the nucleoside.