Sanjana Ahmed
Mariam Afzal, Marya Lopez, Chaya Sussman
Lab Report 1
The Effect of NaCl on the Swimming Speed of Paramecium tetraurelia

An experiment was conducted to see how different pesticides affect organisms, such as Paramecium tetraurelia. Paramecium tetraurelia is a unicellular ciliate from the kingdom Protista. Paramecium move with the assistance of cilia. Cilia are hair like structure surrounding the Paramecium (McMahon, 2016). Paramecium moves in a straight line in water and also can change directions when the Paramecium comes near a solid object or a predator (Deshpande, 2016). One pesticide is sodium chloride (NaCl). Sodium chloride is also known as road salt. Road salt is used to de-ice roadways, driveways and sidewalks. In New Jersey the Department of Transportation stores about 164,000 tons of rock salt (NaCl) to keep approximately 13,000 lane miles of interstate and state highways clear from snow and ice. However, the salt affects the environment. Plants become damaged when roots and foliage are exposed to salt water (Rutgers, 2016). Sodium chloride has a major affect on plants, therefore it can have a negative effect on the movement of Paramecium tetraurelia. An experiment is conducted to see how NaCl effects Paramecium. The question is: what will be the effect of NaCl on the swimming speed of Paramecium tetraurelia. The alternative hypothesis is, sodium chloride (NaCl) increases the swimming speed of the Paramecium. The null hypothesis is; sodium chloride does not have any affect on the swimming speed of the Paramecium. The Predication is if NaCl is added to a culture containing Paramecium then the swimming speed of Paramecium will decrease.


Concentration of NaCl
swimming speed of Paramecium tetraurelia
Paramecium species, size of the electrophoresis chamber, temperature, person observing the Paramecium
Component of Procedure:
Level(s) of Treatment
2 levels of treatment:
0 mM of NaCl
25 mM of NaCl
Control Treatment
0 mM of NaCl
One replication
Sample size (per treatment level)
25 Paramecium per treatment level
Table 1 (Component of experiment)

In the experiment the type of species being used is Paramecium tetraurelia. The materials that were used in this experiment are 225 mL of Dryl\'s solution, 25 mL of NaCl solution, millimeter grid, dissecting microscope and electrophoresis chamber. In table 1 it shows the independent variable is 25 mM of NaCl that was introduced to paramecium culture in the electrophoresis chamber. The dependent variable is the swimming speed of the paramecium in millimeter per second. Standardized variables are the Paramecium species, size of the electrophoresis chamber, temperature, the person observing the Paramecium and scientific apparatuses. There are two levels of treatment 0 mM of NaCl in Paramecium culture and 25 mM of NaCl in Paramecium culture. In the experiment the control treatment is the 0 mM of NaCl in the electrophoresis chamber. In this experiment there is only one replication and the sample size is 25 Paramecium per treatment level.

To start the experiment, place a transparent millimeter grid in an electrophoresis chamber. Fill the chamber with 225 mL of Dryl\'s solution. Using a pipette remove the Paramecium tetraurelia of the container and gently spread the Paramecium on the surface of the electrophoresis chamber. Put the chamber under the dissecting microscope and observe the Paramecium for 5 seconds. Count the number of millimeter squares the Paramecium passes in 5 seconds. Record the swimming speed into a table. Rinse out the chamber and dry it. Repeat all the steps again, but now add 25 mL of 200 mM NaCl after placing the Paramecium in the electrophoresis chamber. Start observing the Paramecium after 2 minutes. After the data was collected a statistical analysis was done using a t-test.

Results and Data Analysis:

Figure 1: Average of the swimming speed for control (0 mM of NaCl) and experimental (25 mM of NaCl)

t- calculated
t- critical
Confidence level
Table 2: Results of the t-test for the swimming speed for the control and experimental

Figure 1, shows the relationship between the average swimming millimeters per second versus the level of treatment. The data indicates that the experimental (25 mM of NaCl) has a greater average swimming speed mm/s than the control (0 mM of NaCl). The control treatment has an average of 1.66 mm/s with the standard derivation of 1.36 mm/s and the experimental treatment has an average of 1.92 mm/s with the standard derivation of 1.63