Daphnia Lab Report

An experiment was conducted to study and explore the circulatory system by exposing Lumbriculus variegatus, black worms, to household drugs. Lumbriculus variegatus was chosen as the experimental organism because of their transparent bodies and their simple physiology.

At first the average Heart rate of Daphnia was 22 with no treatment after measuring it for three times. Afterward when I putted 15% of Ethanol on Daphnia I found out that Ethanol does affect Daphnia and caused to decrease the heart rate of Daphnia after measuring it for three times. Daphnia’s heart rate was decreased by 7 after putting Ethanol. I would classify Ethanol as a depressant because it decreased the heart rate of Daphnia.

The projects purpose was to determine the effects of alcohol and caffeine on the heartbeat rate in Daphnia Magnus. Our hypothesis is alcohol causes a decrease in heart rate, whereas caffeine causes an accelerated heart rate, predicting that the more caffeine we give the daphnia the faster it heartbeat rate will become and the heartbeat rate will decrease as we give the Daphnia alcohol. After doing the experiment we found that the more caffeine we added to the Daphnia Magna the faster its heartbeat rate became. We also found that

This laboratory exercise was performed to visualize the effects of various drugs on the heart rate of Daphnia magna. The four drugs tested consisted of: Lidocaine, Acetylcholine, Caffeine, and Nicotine. These drugs were designed to have an apparent effect on the average heart rate of the Daphnia. The laboratory exercise was divided into two parts and procedures: measuring the basal heart rate of Daphnia, and measuring the drug induced heart rate of Daphnia. In order to measure the basal heart rate, various Daphnia were obtained and observed under a microscope at 40x magnification for two separate trials. Using the same technique, the drug induced heart rate with each drug (Lidocaine, Acetylcholine, Caffeine and Nicotine) was measured and

An electrical stimulus was applied to the heart; the following graph shows the refractory period of the frog’s heart when an extra-systole was induced. It can be seen that right after the recording was marked “Refractory 3,” an extra-systole was detected.

The two drugs that have been used in this experiment to test their effects on the heart rate and depolarization rate of the P wave of the crayfish. Depolarization is defined as the contractions of heart muscle, and it is shown in P wave pattern of the ECG. Comparing the results of the trials of epinephrine drug to the resting state, it shows that this drug increases the heart rate, decreases beat period, and decreases the time that take

To begin the experiment, we took a single Daphnia magna from the unused tank to run control tests with distilled water on the untampered heart rate of the species. The species was placed on a concave slide with a new drop of water on it. It was given 2 minutes of recovery time to adjust to its new environment; then, the heart rate was studied by intervals of 15 seconds to find beats per minute by multiplying the number of beats in 15 seconds by 4. The Daphnia magna was studied under a light microscope with 40x total magnification. After each round of data collection, the water was absorbed with a Kimwipe so a new water drop could be placed on the species. The same Daphnia magna was used for six rounds of control experiments. After

The experiment took place in a laboratory setting, and the first step was obtaining sixty individual Daphnia magna (that were neither adults nor tiny offspring) from a large tank in the lab. These individuals were equally divided into three groups; low density, medium density, and high density. The twenty Daphnia assigned to the low density group were split into four groups of five and pipetted into one of four tubes filled with 10mL of Chlamydomonas algae. The twenty Daphnia assigned to the medium density group were split into two groups of ten and placed into one of two tubes also filled up to 10mL with Chlamydomonas. The final twenty Daphnia were all placed into a single tube filled with 10mL of the algae. In order to avoid suffocation-related

For the first trial, the joint mass of the two goldfishes was 9.32g. Figures 1 and 2 were graphical representations of the oxygen concentration within the chamber over a period of ten minutes for the first trial. Since the decrease of the oxygen concentration is inversely proportional to the increase of oxygen consumption, the following data will report negative rates in oxygen concentration as positive oxygen consumption rates. Figure 1 depicted the data of the controlled run and reported a negative slope, indicating an oxygen consumption rate of 0.0007 mgO2L-1s-1. Figure 2 depicted the data from the experimental run, in which the goldfishes were subjected 100mL of the nicotine-treated fish water. This data from the run revealed a positive slope, which indicated an increase in oxygen concentration; therefore the oxygen consumption rate is a negative value of 0.0001

However, the experimental group did prove a slight consistency. Table 2 displays that in the 0.5 MRR row, the three larvae observed had 4, 6, and 6 waves, with the second and third having the same number of waves. Likewise, the second and third larva in the 1 MRR row also had the same number, only having 2 peristaltic waves. When we increased the MRR to 1.5 and 2, all observed larvae did not move at all. This is because by increasing the MRR, the likelihood of the blue light flashing increases. At 0.5 MRR, the blue light would flash once every two seconds. This allowed the experimental group to slightly move before they were forced to contract when the blue light would shine on them again. Once the MRR was set to 1, the light would flash once every second, decreasing the amount the larva would move and thus, decrease the peristaltic

Introduction Black worms are fun little critters that show us exactly what a simple vascular system looks like, one vein with a head and tail and a slow enough pulse to easily count. Their skin is translucent, so with only a compound microscope you can view the insides of the small worm. Another great quality is that the diffusion of a drug into the worms system is a quick process (Bohrer, 2006). The purpose of this experiment is to see the effect of alcohol on the vascular system of the Lumbriculus Variegatus. My hypothesis was that If Alcohol is exposed to the Black worm them the pulse rate would decrease because to humans alcohol is a depressant.

A Beta fish Methods: The date the column was set up was approximately September 16, 2016. The experiment lasted

When the shrimp was exposed to the caffeine the heart rate increased by 50.4 beats, and when the shrimp was exposed to the ethanol the heart rate decreased by 34.8 beats. The worms average resting heart rate was 21, the heart rate affected by caffeine was 32.83, and the heart rate affected by ethanol was 21. The average increase in heart rate was 11.83 beats, and the average decrease in heart rate was 7.5 beats. From this data we can conclude that caffeine acted as a chemical stimulant and speed up how frequently the heart was pumping blood into the system. Ethanol acted as a chemical sedative and slowed down how many times the heart pumped blood into the system. Even though the two organisms had different circulatory systems, they were still affected in the same manner. The only difference between the two systems during this experiment is open circulatory systems have higher heart rates overall compared to closed circulatory

One way to test how chemicals impact heart rate, would be by testing on a live animal. By using an animal test

According to the NIAAA (National institute on Alcohol Abuse and Alcoholism), the abuse of alcohol affects several areas of the body. Alcohol can cause deterioration of the myocardial cells in the heart, causing the heart to enlarge and droop, this