Title: The Effect of Nicotine on the Heart Rate of the Lumbriculus Variegatus Introduction:
Background- This lab is being done to demonstrate the effects of stimulants on the circulatory system of blackworms. In this lab, the stimulant we have chosen to use is Nicotine. A stimulant is an agent that causes increased activity, especially in the nervous or cardiovascular systems. In this lab, we will put 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 commonly found in North America and Europe. The blood in blackworms circulates from the dorsal blood vessel toward the head through a series of rhythmic contractions. A common pulse rate for the blackworm is 7 to 8 pulse/minute.
Hypothesis- If a stimulant increases heart rate, then when the Lumbriculus Variegatus is put into Nicotine its heart rate will increase. Materials and Methods:
-First, fill a petri dish with water and insert 15 blackworms into the dish from the bucket containing all of the blackworms. Extract one worm into a pipette then insert into the capillary tube. Place the capillary tube under a microscope and adjust until the blood flow is seen. Pick one segment and count how many times it contracts during a minute’s time. Use the pipette and push the worm out of the capillary tube and into another petri dish for “trash”( the petri dish which contains the worms that have already had their control pulse rate counted). Continue these steps doing one control and one nicotine test for each worm and make sure to count pulse rates from the same area of each worm that the data is as consistent as possible. Next, get another petri dish and fill with 2.5 mL of unfiltered non-menthol Nicotine along with 1mL H2O. Take one worm from the “trash” dish and insert into the Nicotine for one minute, make sure to measure how much water is getting into the Nicotine to know how...
Please join StudyMode to read the full document