Growth phase; growth phase curve
The characteristic periods in the growth of a bacterial culture, as indicated by the shape of a graph of viable cell number versus time, namely: lag phase; logarithmic (or exponential) phase; stationary phase; death phase.

Growth rate
Increase in mass per unit of time. See growth

Gynogenesis
Female parthenogenesis; after fertilization of the ovum, the male nucleus is eliminated and the haploid individual (described as gynogentic) so produced possesses the maternal genome only. Cf androgenesis; parthenogenesis; anther culture gyrase see DNA helicase.

GTP
Guanosine triphosphate. See guanosine

Guanine
A purine derivative that is one of the major component bases of nucleotides and the nucleic acids, DNA and RNA

Guanosine
A nucleoside consisting og one guanine molecule linked to t D ribose sugar molecule. The derived nucleotides, guanosine mono, di, and triphosphate (GMP, GDP, and GTP, respectively), are important in various metabolic reactions.

Gynandromorph
An individual in which one part of the body is female and another part is male; a sex mosaic.

Guide sequence
An RNA molecule (or a part of it) which hybridizes with eukaryotic RNA and aids in the splicing of intron sequences. Guide sequences may be either external (EGS) or internal (IGS) to the RNA being processed and may hybridize with either intron or exon sequences close to the splice junction. See split gene; exon.