The Effect of Nicotine on the Heart Rate of the Lumbriculus Variegatus Essay Sample

Background- This lab is being done to show the effects of stimulations on the circulatory system of blackworms. In this lab. the stimulation we have chosen to utilize is Nicotine. A stimulation is an agent that causes increased activity. particularly in the nervous or cardiovascular systems. In this lab. we will set blackworms into the Nicotine to look at the differences in pulse rates when compared to a control. The proper name for blackworms is Lumbriculus Variegatus. they are freshwater worms most normally found in North America and Europe. The blood in blackworms circulates from the dorsal blood vas toward the caput through a series of rhythmic contractions. A common pulsation rate for the blackworm is 7 to 8 pulse/minute.

Hypothesis- If a stimulation increases bosom rate. so when the Lumbriculus Variegatus is put into Nicotine its bosom rate will increase. Materials and Methods: -First. make full a petri dish with H2O and insert 15 blackworms into the dish from the pail incorporating all of the blackworms. Extract one worm into a pipette so infix into the capillary tubing. Put the capillary tubing under a microscope and adjust until the blood flow is seen. Pick one section and number how many times it contracts during a minute’s clip. Use the pipette and force the worm out of the capillary tubing and into another petri dish for “trash” ( the petri dish which contains the worms that have already had their control pulsation rate counted ) . Continue these stairss making one control and one nicotine trial for each worm and do certain to number pulse rates from the same country of each worm that the information is every bit consistent as possible.

Next. acquire another petri dish and fill with 2. 5 milliliter of unfiltered non-menthol Nicotine along with 1mL H2O. Take one worm from the “trash” dish and insert into the Nicotine for one minute. do certain to mensurate how much H2O is acquiring into the Nicotine to cognize how much the solution is thining. This was controlled so that we could do certain each worm was being put into the same strength nicotine solution. Take the worm and set it into a separate pipette and so another capillary tubing and step the pulsation rate for one minute. Take the worm out and set it into the “rehab” petri dish. a topographic point for the worms to acquire their bosom rates back to normal before fall ining all of the worms. Continue these stairss and record the pulse rate one time in the nicotine for each of the worms. Make certain to cipher both the mean and median from both the control and stimulating tests. Consequences:

-The dependant variable is the pulse rate of the blackworms in pulse/min. The independent variable is the nicotine added which is 2. 5mL with 1mL H2O. The same 15 worms were used in both tests ( each worm was tested one time for each ) . the same Nicotine was used for all stimulating tests. worms were in the Nicotine for the same sum of clip. the pulse rate was recorded at the same clip for each worm. same capillary tubings were used. same pipette was used. and worms were put into the same petri dishes. Two tests were done with the Nicotine at 2. 5 milliliter and nine tests were done with 2. 5 mL Nicotine along with 1 milliliters H2O. We had to thin the solution because every worm in the 2. 5mL Nicotine solution died. Spring H2O served as the positive control since it serves as the worm’s mundane home ground. All informations will be compared to this control.

-Table 1 shows the bosom rates of worms in the control. their mean bosom rate is at 10. 7 pulse/min. Table 2 shows the worms in the 2. 5mL of Nicotine which proved to be excessively strong. Table 3 shows the bosom rates of worms in the diluted solution of 2. 5mL Nicotine and 1mL H2O. Table 3 shows that the bosom rate of worms is faster in the nicotine with the mean pulse rate at 15. 5 pulse/min.

-This tabular array shows the information for the 15 control worms in H2O and so the same 15 in Nicotine. There are non 15 worms in the nicotine solution because our first solution was excessively strong and 6 of the worms died. The solution being used in this graph is 2. 5 milliliter of Nicotine and 1 milliliter H20. This graph shows that the pulse rates of worms in Nicotine tend to be higher than that of the worms in H2O. This information proves the thought that stimulants raise bosom rate.

Decisions:
-Nicotine does hold an consequence on bosom rate. Nicotine has shown a raised bosom rate ( 15. 5 pulse/min ) when compared to the control ( 10. 7 pulse/min ) . Based on the background of a stimulation the bosom rates were expected to raise. The one thing that intrigued me was how small nicotine it took to do the difference between decease and a raised bosom rate in the worms. I was intrigued by the fact that as worlds we take in much more Nicotine so that at a clip and are hardly fazed. However. our organic structures and organ systems are much bigger. For farther survey. I would prove this lab with different concentrations of Nicotine to see where the dramatic alterations in pulse semen to play.

Plants Cited:

-Hanes. Tracii. “Facts on Stimulants & A ; Depressants. ” LIVESTRONG. COM. N. p. . 18 Mar. 2011. Web. 20 Sept. 2012. & lt ; hypertext transfer protocol: //www. livestrong. com/article/131357-stimulants-depressants/ & gt ; . -Biology. Boston: McGraw-Hill. Higher Education. 2005. Print.