The answer would be Food being digested in the stomach. Homeostasis is the process the body does to regulate bodily functions.
The Calvin cycle take place in the Stroma of the chloroplast. Calvin cycle is a set of chemical reactions that take place in the chloroplasts during photosynthesis. This cycle is light-independent since it takes place after the energy has been captured from sunlight. The process; involves four main steps; carbon fixation, reduction phase, carbohydrate formation, and regeneration phase.
The finches on the Galapagos Islands are a good example of adaptation because they all trace their ancestry into a small group of finches that inhabited these islands, but diversified in accordance to the environment. On the Galapagos Islands, there are finches that have numerous types of different beak shapes and sizes, despite them all being derived from a single group of finches that had the same characteristics. The reason for this is that once they got to these islands, there were multiple niches int the food chain that were free for taking. Some finches started to feed on plants, some on seeds, some became insect-eaters etc. Every food type needs special adaptation so that the finches can eat it more easily, or even be able to get to its nutritional part, thus their beaks started to change in accordance to their food preference.
Dopamine is a neurotransmitter that is related to the positive feedback/reward system of mammal brains. Higher amounts of dopamine released in response to any stimulation will result in a stronger desire to recreate that stimulus. One could say that the extra dopamine released during drug use causes the brain to desire using the drug again to receive that same pleasurable reward sensation. <span />
