Rate of reaction will increase with the presence of a catalyst.
This is due to catalysts providing an alternative reaction pathway with lowered activation energy required, allowing an increased rate of reaction.
Genetic drift happens by chance and can make an allele disappear completely from a gene pool, even if it was a desirable trait that should have been passed down to offspring. The random sampling style of genetic drift shrinks the gene pool and therefore alters the frequency the alleles are found in the population.
Helicase "unzips" the two strands of DNA. During DNA replication.
<span>Ions are another name for charged atoms. Some elements are electropositive, and some are electronegative. Electropositive elements such as metals like to give up electrons, thus taking on a positive charge. Electronegative elements such as chlorine attract electrons, so they become negative. When electropositive and electronegative atoms meet and exchange ions, they take on opposite charges. Because positive and negative charges attract, these charged atoms become attracted to one another. This attraction forms an ionic bond that keeps the ions together.</span>
