Using a double pithed frog, three drug solutions were applied to the isolated frog heart. When applying the solutions to the heart, one to three drops were applied each time. Potassium, Calcium and caffeine were applied to the heart as inotropic and chronotropic affects were measured. Between each drug application, ringer solution was applied to the frog heart. Ringer solution is used to keep the frog wet and to rinse out each drug before applying the next. When measuring potassium (K+), the expected inotropic effects was negative and the observed was no effect. The expected chronotropic effects for K+ was negative and the observed was also negative. For calcium (Ca2+), the expected inotropic effects were positive and the observed was positive. The expected chronotropic effects for Ca2+ was positive and the observed was negative. When measuring caffeine, the expected inotropic effects was positive and the observed was also positive. The expected chronotropic effects for caffeine was positive and the observed was positive.
Discussion:
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However, K+ had no effect on the strength of contraction. The expected chronotropic effects were negative and the observed was also negative, so the heart rate decreased as anticipated. For Ca2+ the expected inotropic effect was positive as was the observed. For this result, there was strong evidence to show the increased strength of the heart contraction. The expected chronotropic effect for Ca2+ was positive were as the actual effect was negative. One possible reason for this discrepancy could be that not enough ringer solution was used and the drug solutions were not properly rinsed out. The expected inotropic effect for caffeine was positive as was the observed. Also, the expected and observed for the chronotropic effect was both positive. As expected, caffeine increased heart rate and strength of contraction. There was strong evidence to prove this
Nerve stimulation was induced for every fifteen seconds at an increment frequency of 0.5 pps (parts per seconds), 1.0 pps, 2.0 pps, 4.0 pps, 8.0 pps, 15 pps, and 25 pps. Every increment trial had a thirty-seconds waiting period. To witness the effects of tubocurare on muscle activity, the baseline was maintained between 20-30 grams and a control was established by turning the stimulator on repeat for 60-120 seconds. Then 0.25 ml of tubocurare was infused into the gastrocnemius muscle. The data was recorded for ten minutes.
I predicted that the blackworms in higher caffeinated solutions would have higher pulse rates, because caffeine is known to increase blood pressure and heart rate. However as far as scientists know, invertebrates are not expected to have a strong response to caffeine like vertebrates do. Also, caffeine in low doses is known to lower pulse rate. The results do not support my hypothesis. The results show that when black worms are placed in caffeinated solutions, their pulse rates on average are lower than those placed in a solution with no caffeine. A possible flaw that may have occurred during experimentation is that the petri dishes were not properly cleansed, or that there were other properties in the water that influenced the outcome. To eliminate these flaws, I could have boiled the petri dishes and water to insure that there were no other properties to influence the data. Further experimentation should be performed with higher doses of caffeine to further insure that caffeine does in fact lower their pulse rate. The insufficient number of trials performed lead to less confidence in my conclusion that caffeine lowers the heart rate in
Also, we learned that depressants decrease the heart rate because they influence the parasympathetic nervous system which responsible for the rest and digest and depress the sympathetic nervous system (Silverthorn, 2010). The main stimulator in Red Bull is caffeine, it functions by blocking the effects of the adenosine, a brain chemical involved in sleep. When caffeine blocks adenosine, it causes firing of neurons that stimulate the sympathetic system, that triggers "fight or flight" response by releasing adrenaline. Adrenaline is a hormone that increases the heart rate and dilate the eye; another effect of Caffeine is changing the levels of dopamine, responsible for pleasure in the brain (Kollmorgen, 2011). We will be comparing the components individually to the baseline, we will also be testing the components in combination compared to their results individually and baseline. Our baseline will be aged tap
The use of model organisms in pre clinical trial is relied upon for the collection of safety and efficacy data prior to first in human clinical studies. The crustacean Daphnia magna is one model organism, whose heart rate is reported to react similarly to the human heart rate, when exposed to identical compounds (3).
3. Effects of resistance training and Chromioum Picolinate on body composition and skelatal muscle in older men by, Campbell WW., Joseph LJ., Davey SL., Cyr-Campbell D., Anderson RA., and Evans WJ.. JOURNAL OF APPLIED PHYSIOLOGY. 86(1): 29-39,1999 January.
In the Tell-Tale Heart the story speak about a murder. The narrator telling the story
Caffeine, a central nervous system stimulant, is the main psychoactive ingredient in energy drinks, which enhances alertness and mood, and counteracts symptoms of sleep. There is no doubt ...
... uptake during submaximal exercise but did increase heart rate and the rate-pressure product at rest and during both exercise and recovery’.
The second part of this lab was a computer simulation program to illustrate a frog’s electrocardiogram using various drugs in an isolated setting. The computer program entitled “Effects of Drugs on the Frog Heart” allowed experimental conditions to be set for specific drugs. The different drugs used were calcium, digitalis, pilocarpine, atropine, potassium, epinephrine, caffeine, and nicotine. Each of these drugs caused a different electrocardiogram and beats per minute reading. The calcium-magnesium ration affects “the permeability of the cell membrane”(Fox). When calcium is placed directly on the heart it results in three physiological functions. The force of the heart increases while the cardiac rate decreases. It also causes the appearance of “ectopic pacemakers in the ventricles, producing abnormal rhythms” (Fox). Digitalis’ affect on the heart is very similar to that of calcium. It inhibits the sodium-potassium pump activated by ATP that promotes the uptake of extracellular calcium by the heart. This in return strengthens myocardial contraction (Springhouse). Pilocarpine on the other hand
The Tell-Tale Heart: An Analysis In Edgar Allan Poe’s short-story, “The Tell-Tale Heart,” the storyteller tries to convince the reader that he is not mad. At the very beginning of the story, he asks, "...why will you say I am mad? " When the storyteller tells his story, it's obvious why. He attempts to tell his story in a calm manner, but occasionally jumps into a frenzied rant.
Edgar Allan Poe author of “The Tell-Tale Heart” used literary devices to create mystery and suspense. Poe used personification in the 2nd paragraph which added character to his story, “evil eye”. This is an example of personifications because an eyeball cannot be evil itself, Poe gave the cataract eye the characteristic of evilness to suggest to the reader that it was really a bother to him. “Black as pitch” found in paragraph 3, is an example of a simile. By using a simile in his story I think that Poe gave his story variety. He described the rooms lack of light through a simile which was very creative in my opinion. Finally, Edgar Allan Poe uses imagery repeatedly to help the reader picture what is going on in his story. An example of this
Graham, TE. (1998) Effects of Caffeine on Metabolism, Exercise Endurance and Catecholamine Responses and Withdrawl. London
"Potassium: Heart Benefits and Side Effects." WebMD. WebMD, n.d. Web. 22 Apr. 2014. (This source is credible because it is a medical cite that discusses halth benefits or conditions).
In the “Tell-Tale Heart” by Edgar Allan Poe, the narrator is extremely uncanny due to the reader’s inability to trust him. Right from the beggining the reader can tell that the narrator is crazy although the narrator does proclaim that he is sane. Since a person cannot trust a crazy person, the narrator himself is unreliable and therefore uncanny. Also as the story progress the narrator falls deeper and deeper into lunacy making him more and more unreliable, until the end of the story where the narrator gives in to his insanity, and the reader loses all ability to believe him.