Examples of caffeine

• Caffeine wakes us up and gives us energy. 

• Many people like tea and coffee because of the caffeine in these drinks. 

• Effects of Tea and Coffee. —In addition to the stimulating agent caffeine, tea and coffee contain a bitter, astringent substance, known as tannin. 

• In chemical composition caffeine closely resembles a waste, called uric acid, and in the body is converted into this substance. 

• Tea and coffee contain a drug, called caffeine, which acts upon the nervous system and which may, on this account, interfere with the proper control of the heart. 

• The first trial to combat or prevent this drowsiness was made with caffeine. 

• They are usually so addicted to caffeine, cigarettes, alcohol, and so forth, that when they had fasted, even briefly, their bodies were forced to dip into highly-polluted fat reserves while simultaneously the body begins withdrawal. 

• These results clearly indicate that caffeine treatment during prolonged maturation culture decreases the frequency of development to the blastocyst stage but not embryo quality.