Z	Z	In proteins, when you don't know if the amino acid is Glutamine or Glutamic acid. Sometimes you can't tell because of the amide could be hydrolyzed during purification.
	zcat	A UNIX command that uncompresses one or more .Z files to the standard output, leaving the original compressed files unchanged.
	Z DNA	A conformation of DNA in which the two polynucleotides are wound into a left-handed helix.
	zinc finger	A common motif for a transcription factor.
	zoo blotting	A technique that attempts to determine if a DNA fragment contains a gene by hybridizing that fragment to DNA preparation s from related species, on the basis that genes have similar seqeunces in related species and so give positive hybridization signals, whereas the regions between genes have less similar sequences and so do not hybridize.
	Z score	Standard normal deviate, or standardized score. The Z score measures the distance of a value from the mean of a distribution in standard deviation units, Z = (value - mean)/sigma. In sequence analyses, the mean an dstandard deviation are usually those of unrelated or randomized sequences.
	zwitterion	A dipolar molecule, having both positive and negative charged regions
	zygote	A cell resulting from fusion of gametes during meiosis
	zymogen	Enzymatically inactive precursors of proteolytic enzymes.