Topic Genetics of Bacteria Essay - Main Points!

Q) Suggest the significance of operons in prokaryotes

Main points
Key idea:	Bacteria respond to the environmental conditions
· Bacteria able to utilize a variety of sugars for energy needs · Absence of lactose in the environment - no need for enzymes, so enz not synthesized · Enz only synthesized when lactose present, to break down lactose to glucose + galactose
Key idea:	Dual roles of glucose
· If glucose and lactose preent, glucose is preferred as respiratory substrate for syn of ATP (cellular respiration) · Glucose help to switch off lac operon (i.e. glucose repression)
Key idea:	Operons allow economic use of limited cellular resources
· Operons - help direct limited resources and energy of the bacteria toward other important metabolic activities · Via coordinated control of genes involved in a metabolic activity (e.g. lactose metabolism)
Comments: (i) Visualize the answer with the aid of labelled diagram + animation (ii) Verbalize the answer + write down the main points w/o referring to the answer (use abbreviations) (iii) Read again within the next 24h & once more within 72h (do not spend more than 10min) (iv) Operon system has its advantages and limitations. Unlike euk cell sys, it is unable to fine-tune expression level of each gene (x/ref to Control of Eukaryotic Gene Expression)