There are two chair conformers for cis-1-ethyl, 3-methylcyclohexane. Which is the more stable conformer? Provide an explanation.
The conformer that contains the methyl and ethyl groups in the equatorial position is more stable. This position is lower in energy because axial positions put the groups gauche to the ring where it experiences 1,3-diaxial interactions.
Both Mg2+ and Ca2+ are important biological ions. One of their functions is to bind to the phosphate group of ATP molecules or amino acids of proteins. For Group 2A metals in general, the tendency for binding to the anions increases in the order Ba2+ < Sr2+ < Ca2+ < Mg2+. Explain this trend.
The binding of a cation to an anion results from electrostatic attraction. As the +2 cation gets smaller (from Ba2+ to Mg2+), the distance between the opposite charges decreases and the electrostatic attraction increases.
How does the lymphatic system prevent edema?
The lymphatic system returns fluid from the interstitial fluid back to blood.