The reasoning behind this is because these unidentified plants could be used to cure diseases, used for food, and many scientists may even use these plants to create cosmetics. I really hope this helps and I just thought this off the top of my head so its may not be 100% accurate but its the basics of it.
Designing efficacious norovirus vaccines remains a major challenge due to several factors:
(1) the extreme genetic variability within the norovirus family and within genogroups
(2) the rapid evolution of antigenically dissimilar pandemic GII.4 norovirus strains
(3) the lack of lasting immunity upon natural exposure to noroviruses in at least a proportion of the population.
Answer;
An example of positive feedback loop is;
-When a pregnant woman begins to go into labor, the body sends hormones that increase the intensity of the labor contractions.
Explanation;
-Feedback loops are therefore the process whereby a change to the system results in an alarm which will trigger a certain result. The result will then either increase the change to the system or reduce it to bring the system back to normal.
-Feedback loops are important because they allow living organisms to maintain homeostasis (maintenance of internal environment of the body constant).
-A positive feedback loop occurs in nature when the product of a reaction leads to an increase in that reaction. It moves a system further away from the target of equilibrium, by amplifying the effects of a product or event and occurs when something needs to happen quickly.
1. add heat and components with lower boiling points will evaporate while heavier molecules will turn back into liquid
2. vapor reaching the top of the column is collected in an industrial condenser
3. substances remaining the the column continue the process
