The bacterium, E. coli prefer to consume glucose. If, however, there is no glucose present, they will utilize lactose as an energy source. Which of the following is the regulatory mechanism occurring when there is no glucose, but there is lactose

Lactose is more likely to be utilised by E. Coli than Arabinose because Lactose will yield more energy (ATP) and lactose breakdown will give glucose and galactose and these will enter into the glycolytic pathways to pyruvate for ATP generation until Arabinose which will undergo Pentose phosphate pathway and this does not produce enough energy.

"menstrual cycle is a complex cycle that consists of several processes. order of occurrence of steps in menstrual cycle are as follows:

1. high progesterone levels maintain the endometrium lining of the uterus.

2. endometrium lining breaks down and low levels of estrogen stimulate the pituitary to release fsh and lh.

3. fsh and lh stimulates the follicles to develop and the oocyte to produce estrogen.

4. rising estrogen levels suppress fsh production and development of other follicles.

5. a spike in lh causes follicle to rupture.

6. a breakdown of corpus luteum causes progesterone level to drop."