What are external cues/signals and how does it affect hunger?

When exposed to the food more often, the dopamine response transfers onto cues that are associated with food reward, for example the sight or smell of the particular food. Already the smell of a food can induce a dopamine response in the brain and becomes a predictor of reward.

Like many students at university, you may be unhappy about the results you attain in exams. you may feel that even with all you are doing there must be something more -- or different-- you could be doing to get better grades. we have all at some time or other heard of that student who only studies a couple of hours for final exams and scores a's every time. we stand in awe of those who seem to breeze through without undue effort and seem to need very little in the way of studying to nail an exam. the reasons for success, in what i think are the vast majority of cases, are less esoteric than many students think: successful students consistently apply a series of productive strategies with view to attaining clearly identified learning and grade goals throughout the academic term.

Based off the appearance of the peppered moth, its markings would not be advantageous in a lush green ecosystem . this could cause their population to decrease as the camouflage factor would be somewhat useless and make them much more vulnerable to predators .hope this : )