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Knowledge of earth system in order to protect, understand and develop research methods.
Lac genes are most effectively expressed in presence of Lactose and its analogs when glucose is absent.
Explanation:
A unit of prokaryotic gene expression and regulation,which includes structural genes and regulatory sequences recognized by regulatory gene product is called operon.
<em>Lac </em>structural genes are a part of<em> Lac</em> operon. The <em>Lac </em>operon consists of three, structural genes,an operator and a promoter.The product of Lac operon is involved in the conversion of disaccharide lactose into glucose and Galactose.
Lactose and its analogs are inducers of<em> Lac </em>operon. So, the structural genes are best expressed in presence of Lactose. Glucose and galactose are repressors of lac gene so the genes are repressed in presence of glucose.
The endoplasmic reticulum, or ER, and Golgi apparatus, prepare molecules, including proteins, hormones and lipids, and package them in vesicles for transport. Rough ER is studded with ribosomes that synthesize proteins, while the smooth ER manufactures lipids.
Answer:
The Marburg virus wasn't mutating this early on, therefore the Coronavirus is much more deadlier and almost impossible to get a cure for, due to the rapid change in pathogens!