Chemistry , the science of the composition of substances, underlies biology. This week, we will highlight some important aspects.
Atoms combine to form molecules .
When atoms interact chemically to form molecules, they are held together by bonds . Acidic solutions are 6.9 and less, and alkaline are 7.1 and up. Buffers are substances that help to maintain neutrality, near where most animal cell activity takes place. Water is polar and has lots of hydrogen bonds. It is therefore a universal solvent and has a high boiling point, a high capacity to absorb heat, and lower density as a solid than as a liquid.