Cell Respiration and Aquatic Animal Aim: To investigate the effect of a change in the temperature of water on the respiration rate of a goldfish. Research question: Does a change in temperature of water affect the respiration rate of a goldfish? Introduction: “The goldfish is a domesticated subspecies of a carp like fish called Carcasses erratum. Goldfish are usually kept as pets, feeding on fish food, algae, plankton and other small aquatic life forms.
Though goldfish are one of the easier species of aquatic life to care for, their respiratory systems are Just as complex as any other fish. Like other aquatic animals, goldfish have a one-way flow respiratory system. This means that their respiratory system pumps water through their gills and back into the water supply to absorb oxygen. Gills–which are the organs that most aquatic animals use to breathe–consist of complex filters that extract oxygen from the water. ” There are many factors that can affect the respiration rate of an aquatic animal including temperature of water, oxygen levels, crowding, and pH levels.
When the water temperature is raised, the goldfish will experience a spike in metabolic activities. It will require more food and will produce more waste. In order to support the increased activity, the goldfish will require more oxygen. Rate of respiration will increase and the goldfish may even gasp for air at the water surface. ” Hypothesis: As the temperature of water decreases, respiration rate of the goldfish also decreases. This is because in lower temperature, water can hold more dissolved oxygen compared to water with higher temperature, thus rate of respiration becomes lower as enough oxygen are supplied.
Variables: Variables I Method of controlling I Independent variable I Temperature of watery Dependent variable I Respiration rate of the goldfish I Controlled variable I 1. Type and number offish used. * A goldfish of species ‘Carcasses erratum’ is used throughout this experiment. 2. Timeshare for counting propeller movements of the goldfish. * The goldfish’s propeller movements are observed during 1 minute timeshare. 3. Number and size of beakers used. * 3 beakers of volume 500 ml are used for different water temperatures.
I Table 1 shows the independent, dependent and controlled variables and methods to control them. Apparatus and materials: Apparatus I Quantity (s) I Container/tank | 1 500 ml beaker | 3 | Thermometer | 1 Stopwatch | 1 Glass rod | 1 Fishnet | 1 Table 2 shows the apparatus and its quantity needed in the experiment. Materials I Quantity (s) I Goldfish II Hot water I Less than 500 ml I Crushed ice I Half-filled beaker I Plastic zip-lock bag | 1 Masking tape (for labeling purpose) | 1 Table 3 shows the materials and its quantity needed in the experiment.
Method: 1 . Prepare 3 different 500 ml beakers and label them A, B and C for different temperatures of water each. 2. Remove a goldfish from the tank carefully using a fishnet and place it inside a plastic zip-lock bag containing half filled water from the same tank. 3. Fill beaker A with about 450 ml of water of room temperature and place the plastic zip-lock bag containing the goldfish in it slowly. Let the goldfish adjust to the water temperature and observe its propeller movement which opens and closes in rhythm with the opening and closing of the mouth. 4.
Insert a hermetic inside the plastic zip-lock bag to measure its temperature and record it in a table. 5. Start the stopwatch and count the number of propeller movements of the goldfish for 1 minute timeshare. Conduct 2 more trials and record them in the data collection table. 6. Next prepare beaker B containing water and adjust its temperature to 10 degrees below the room temperature measured earlier by adding crushed ice and stirring it for uniform temperature. 7. Again, slowly add the plastic zip-lock bag containing the goldfish into the beaker and let it adjust to the new rounding temperature.
Using a thermometer, make sure that the temperature of water inside the plastic zip-lock bag has fallen 10 degrees under the room temperature. 8. Repeat step 5. 9. Lastly, prepare beaker C which contains hot water and adjust its temperature until it reaches 10 degrees above the initial room temperature. Stir the water using a glass rod to ensure uniform temperature throughout the beaker. 10. Place the plastic zip-lock bag with the goldfish in beaker C and let it adjust itself to the new temperature of water.