Essay --

Investigating the effect of caffeine concentration on the warmth prize of water fleaIntroductionDaphnia, commonly known as weewee fleas, are tiny crustaceans which live in water. The diameter of adult womanly bodies is approximately 3-5 mm. The upper skeleton is transparent, making the internal organs visible. This allows the warmness cast of the Daphnia to be calculated by observing them beneath a microscope. BackgroundCaffeine occurs naturally in some plants such as coffee beans and tea leaves. Caffeine is also added to other beverages. boozing containing caffeine (100ml)Amount of caffeine (mg)Caffeine per 1ml of beverageCoffee550.55mgTea350.35mgCoca Cola150.15mgCaffeine is medically known as trimethylzanthine. Caffeine acts as a cardiac exhilarating which means that it increases life rate.Adenosine is a natural chemical found in the body which binds to respective adenosine receptors in the sinoatrial node and slows down the activity of the nerve cells. Caffeine also bi nds to these receptors which results in the activity of these nerve cells to increase. Caffeine pulmonary tuberculosis also causes the adrenaline hormone to be released into the body, further increasing the pelt along of bodily functions. Caffeine also constricts blood vessels which is why some annoying medicine and painkillers contain sources of caffeine. 2 cups of strong coffee has been staten to increase heart rate in humans by about 15 defeat per minute.HypothesisAs the caffeine concentration increases, so does the heart rate of the daphnia.PredictionThe prediction for this experiment is that the high the concentration of the caffeine, the higher the heart rate in beats per minute. This is because caffeine acts as a stimulant, make the adrenaline hormone b... ...d by the lamp being on cannot be slow controlled and could be a factor for the increasing heart rate. The heart rate may also increase as a result of the efforts of the Daphnia in escaping from the cavity slide due to limited water supply.decisivenessThe results of the experiment indicate that the initial hypothesis was acceptable as the higher the caffeine concentration, the higher the heart rate of the Daphnia. The results do not show this link in all cases this could be down to temperature rise because of the hotness produced by the microscope lamp, leading to the heart rate of the Daphnia increasing. This could explain the results for the 0.2% caffeine concentration. To improve the accuracy of the results, the same person should conduct all of the experiments as different people may count the heart rate at different speeds, leading to variation in the results.