These eggs belonged to a(n) <span>mollusc</span>
Adenine, guanine, thymine and cytosine are the four nitrogenous bases that are attached to a sugar molecule<span> on each </span>side of the ladder<span>. When a phosphate, a sugar and a base form an attachment, they create a sub-unit of </span>DNA<span> called a nucleotide. Each nitrogenous base is held together by a hydrogen bond.</span>
Albert Alexander was the first patient to be successfully treated on an infection caused by bacteria. He accidentally scratched a thorn of a rose on his face which badly infected him. One of his eyes had also been removed. He was given an infusion<span> of 160 mg of penicillin on February 12, 1941, and within 24 hours, his wounds begun to heal. He, however, died on March 1941. </span>
When atoms in a covalent bond share electrons unequally (one atoms pulls more than the other), the bond is said to be a polar bond is formed when electrons are unequally shared between two atoms. Polar covalent bonding occurs because one atom has a stronger affinity for electrons than the other (yet not enough to pull the electrons away completely and form an ion).
