Data analysis and t-test statistics have supported the hypothesis that Daphnia heart rate would increase when exposed to tobacco extract. Furthermore, tobacco exposure had negatively affected the overall health of the Daphnia specimen. Its heart rate became unusually low, and even after the release to its culture it appeared to be motionless, and possibly died as a result of the experiment. Unfortunately, the concentration of the tobacco extract was unknown, and had it been lower, the effects could have been different. Nonetheless, the experiment was successful due to the supported hypothesis.
According to Stein, the structural features of Daphnia heart is similar in many ways to the cardiac hearts of the vertebrates. Therefore, studying
Internal temperatures can modify the contraction of the heart by increasing or decreasing heart rate.5 The goal of the experiment was to subject the crayfish to different conditions to monitor the change in contractility of the
The hypothesis for this experiment is that if daphnia are exposed to ethanol, aspirin,
The Addition of Caffeine and Nicotine to the Circulatory System of Lumbriculus variegatus and the Effects on the Organism’s Pulsation Rate INTRODUCTION Lumbriculus variegatus, also known as blackworms, are relatively small specimen. Their physiology is so simple that the organisms lack a respiratory system and heart. Henceforth, blackworms rely on diffusion in means of gas exchange through their tail segments and muscle contractions of the dorsal blood vessel (Laboratory Manual BIO 10200, p.69).
Tobacco (Nicotiana tabacum) was the plant chosen for the experiment. Since, nicotine in tobacco is a stimulant, it is predicted that if Daphnia exposed to this substance would have an increased
Poe’s stories “Cask of Amontillado” and “The Tell-Tale Heart” display the dark romantic theme of a man’s soul by the development of the setting, plot, and characterization. As both stories begin, the initial device used to advance the theme is setting, which remains grim and sinister throughout the duration of both stories. Accompanying these physical details is the plot, each of which includes the murder of an innocent man. Most notably, the characterization of each piece’s narrator allows the audience to fully understand their internal struggle and its final resolution. While “Cask of Amontillado” contains an overall intriguing and unexpected plot as well as setting, the narrator’s characterization proves this story to conclude in a less
This laboratory experiment involving invertebrates is conducted to enable students to investigate Daphnia magna’s responses to external stimuli, therefore developing a better understanding and knowledge of homeostasis that occurs in organisms and the reaction and behavior exhibited by the daphnia magna when varying conditions are exposed to the organism compared to its natural environment conditions (Carter-Edwards et al, 2011). In order to understand the experiment, a foundation of information about the chosen organism such as its natural environment and physiology must be understood. According to Clare (2002) and Ebert (2005), Daphnia magna are small planktonic crustaceans belonging to the subclass Phyllopoda, found in lakes and
Daphnia are grown as fish food, and used to test ecotoxicity. Ecotoxicology is defined as, "the branch of toxicology concerned with the study of toxic effects, caused by natural or synthetic pollutants, to the constituents of ecosystems, animal (including human), vegetable and microbial, in an integral context” (Truhaut, 1977). The experiment discussed in this lab report was performed on daphnia, exploiting their transparency which renders them the ideal organism, to test effects of various stimulus on cardiac activity. Past research studies have found ethanol to produce a depressant effect, one similar to the depressant effects of melatonin, and GABA. In contrast, Corotto (2010) has experimented on stimulants, e.g. nicotine, and found an approximate 20% increase in HR.
There are so many different ways to relay a message to a reader using different types of figure of speeches, symbolism being one of the greatest forms of figure of speech. Symbols uses ideas or qualities to represent indirect suggestions to express emotions, natural objects, symbolic images or facts. In Edgar Allen Poe’s two short stories “The Tell-Tale Heart” and “The Cask of Amontillado” show great representations of death by using symbolism, while in “The Tell-Tale Heart” uses the setting, title and amontillado. In the short story “The Tell-Tale Heart” the author uses the man old man’s eye as a symbol.
Nonetheless, besides fish, many other kinds of poikilothermic animals, such as snakes and frogs, use lungs instead of gills to breathe, and further researches may be conducted to explore if caffeine has an effect on their metabolism. For example, forty northern leopard frogs with similar body size will be captured and divided into twenty trials, and each two frogs will be tested in the same control and experimental conditions as the goldfish metabolism experiment did. The collected slopes of oxygen concentration will then be converted into oxygen consumption rate and analyzed by the paired t-test. If the difference in the oxygen consumption rate between the control and experimental groups is statistically significant, this experiment will show that caffeine affects the metabolism of frogs, one kind of poikilotherms that use lungs to
Based on the results the hypothesis is correct that if tobacco extract is added to food vacuoles that less vacuoles will be visible and cellular process would slow down. The contamination of samples and the use of tetrahymena in which most of the cells in the samples were dead made it difficult to get a ratio of cells to vacuoles that accurately depicted the difference between cells with nicotine and cells without. Factors that affected the accuracy of the experiment was unfamiliarity with the equipment and difficulty of find the cells on the slides. One questions posed is at what concentration of nicotine would other cell functions begin to shut down. From this experiment, we can see that the assumption we made about human appetite suppression could be
“He saw that he was stone dead. His eye would be trouble no more.” (Poe, 1843) In the horror story, “A Tell-Tale Heart” by Edgar Allan Poe, it revolves around a first-person view of an unnamed narrator. He is dedicated to killing an old man, because of his “eye of a vulture.”
Corotto, F., Ceballos, D., Lee, A., & Vinson, L. (2010). Making the Most of the Daphnia Heart Rate Lab: Optimizing the Use of Ethanol, Nicotine & Caffeine. The American Biology Teacher , 176-179. The purpose of this article was to test the effects of chemicals on Daphnia magna.
“I've heard many things in the heaven and in the earth. I've heard many things in hell”(Poe). In the story The tell tale heart, a man ends up killing his old man over his “Vulture eye”. He loved the old man. But his “evil eye” vexed him and he decided to take his life.
Even though most of the results produced match almost accurately with the expected responses from the daphnia based on scientific theories, there were some flaws and abnormalities in this experiment which may be due factors such as the initial health condition of the daphnia which causes the daphnia to be extra susceptible and weak towards extreme changes in surroundings. Apart from that, size of the daphnia also makes a difference in the result of the experiments. For instance, larger sized daphnias may have its effect “kick-in” slower than smaller sized daphnias due to difference in volume and surface areas of the organism exposed to the variables, which can impact the consistency of the
Edgar Allan Poe was one of the world’s greatest and most influential connoisseur of short story. He was born on 19th January 1809 in Boston, orphaned at an early age and adopted by a merchant called John Allan from Richmond, Virginia. The Tell-Tale Heart was one of Poe’s famous short stories and it was first published on the 1843. The Tell-Tale Heart is generally considered as a classic of the Gothic fiction genre. If The Tell-Tale Heart was a song, it would be such a painful song to be listened to.