Introduction
Daphnia are a common freshwater zooplankton, they are a member of the crustacean family. Daphnia are ectothermic animals which means their core body temperature fluctuates depending on the temperature of their environment. Temperature has a powerful effect on the biological processes of ectothermic animals. Acute changes to water temperature can have major impacts upon genetic growth and development as well as physiological and metabolic processes. Changes in temperature that remove Daphnia outside their optimum temperature range can affect processes such as oxygen transport, heart and ventilation rates in ectothermic animals. Daphnia make excellent subjects for studying the effect of temperature on ectothermic animals because
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Place a small amount of Vaseline into the middle of the depression on the half cavity slide.
2. Using the cut-down dropper pipette capture a large specimen of Daphnia in a small volume of water. Place the daphnia you have collected over the small amount of Vaseline on the slide, take care that the small volume of water the Daphnia is contained in does not overflow the depression in the slide.
3. Very carefully, place the coverslip over the depression in the slide containing the Daphnia, press the coverslip down gently, until the Daphnia is restrained by the pressure of the coverslip and is stationary, also while doing this try and remove any air bubbles that form. Try to position the Daphnia in the centre of the depression. Before starting the experiment make sure the heart is visible and that you can see the heartbeat of the Daphnia.
4. In a polystyrene cup, mix both warm water and cold water together until you achieve a temperature of 15o C. Place the slide with the Daphnia, into the bottom of the insulated plastic container and add in the 15o C water to just below the rim of the
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The Levene’s F-test shows if there is statistically significant differences between the p-values, if your p-value is under 0.05 there is a statistically significant difference in homogeneity of variances in the different samples, but if your p-value is over 0.05 there is no statistically significant difference. The Levene’s statistic is 2.228. The results of the Levene’s F-test was 0.065 which is over the expected p-value, this shows there is no statistically significance difference in homogeneity of variances. There are two degrees of freedom for the test for homogeneity of variances in the data, the ‘df1’ = 4, ‘df2’ =
2. Drop a gummy bear into each of your prepared beaker or cup and place the beaker or cup
A total of twelve Daphnia magna were used for this experiment; two Daphnia magna were exposed simultaneously to each of the five chemical
In the following experiment, we will attempt to examine the relationship between metabolic rate and environmental temperature in both an ectoderm and an endotherm. I predict that for the ectotherm, the metabolic rate will increase as the outside environment temperature will increase. I also predict that the metabolic rate in the endotherm will remain relatively the same as the outside environment temperature changes. I also make the prediction that the ectotherm will have much lower metabolic rates than the endotherm.
The purpose of this study is to examine Desdemona and whether or not she has dependant personality disorder. Characterized by a clinging behavior and a fear of separation, this disorder usually emerges in early adulthood. If someone does have dependant personality disorder they urgently seek relationships or someone to rely on to the point that someone will not share opinions that seem unappealing (DSM, 675). Based on Desdemona’s actions and speech it is believed that she has dependant personality disorder.
4. Pour about 300mL of tap water into the beaker. Set up a hot-water bath using a hot plate, retort stand, and thermometer clamp. Alternatively, use a Bunsen burner, retort stand, ring clamp, thermometer clamp, and wire gauze.
Now, assemble and arrange all of the needed supplies so that they are easily accessible. Connect the IV tubing to the solution bag and allow the fluid in the bag to run through the entire length of the tubing, also known as priming the tubing. When this is done, clamp the tubing closed. You will then need to tear several pieces of tape, six to eight inche...
Plan 1. Collect 4 different sized beakers 2. Boil some water in the kettle 3. Pour 50ml into each beaker 4. After 1 minute check temperature 5.
The Artemia franciscana can survive in extreme conditions of salinity, water depth, and temperature (Biology 108 laboratory manual, 2010), but do A. franciscana prefer these conditions or do they simply cope with their surroundings? This experiment explored the extent of the A. franciscanas preference towards three major stimuli: light, temperature, and acidity. A. franciscana are able to endure extreme temperature ranges from 6 ̊ C to 40 ̊ C, however since their optimal temperature for breeding is about room temperature it can be inferred that the A. franciscana will prefer this over other temperatures (Al Dhaheri and Drew, 2003). This is much the same in regards to acidity as Artemia franciscana, in general thrive in saline lakes, can survive pH ranges between 7 and 10 with 8 being ideal for cysts(eggs) to hatch (Al Dhaheri and Drew, 2003). Based on this fact alone the tested A. franciscana should show preference to higher pH levels. In nature A. franciscana feed by scraping food, such as algae, of rocks and can be classified as a bottom feeder; with this said, A. franciscana are usually located in shallow waters. In respect to the preference of light intensity, A. franciscana can be hypothesized to respond to light erratically (Fox, 2001; Al Dhaheri and Drew, 2003). Using these predictions, and the results of the experimentation on the A. franciscana and stimuli, we will be able to determine their preference towards light, temperature, and pH.
Start with the hot water and first measure the temperature. Record it. 8. Then pour 40 ml into the beaker. You can measure how much water was used by looking at the meniscus.
Prepare casts of the leaves surfaces by painting the adaxial (top surface) of one leaf and the abaxial (bottom surface) of the other leaf with clear nail polish. Allow the nail polish to dry for approximately 10 minutes. While the nail polish is drying, label microscope slides as either adaxial (top of the leaf) or abaxial (bottom of the leaf). Cut a piece of sellotape approximately 1.5 cm in length. Fold the tape over on itself leaving 0.5 cm of sticky surface exposed.
5.) One at a time, place your test tubes in the water bath and heat the first test tube to 25 , the second to 50 , the third to 75, and the last to 100 degrees c. Remeber to stir with your stirring rod every so often.
In a 100ml beaker place 50mls of water, measure the temperature of the water and record this initial temperature onto a table. Set the timer and add one teaspoon of Ammonium Nitrate to the water, stir this continuously until the Ammonium Nitrate has dissolved.
The purpose of this lab was to study the response of the genus Daphnia to chemical stimuli and to examine human responses to different stimuli. A stimulus is an incentive; it is the cause of a physical response. Stimuli can have a physical or chemical change; an example of a physical change is a change in temperature and sound. An example of chemical change would be changes in hormone levels and pH levels. Muscular activity or glandular secretions are responses that occurs when stimulus information effects the nervous and/or hormone system. Daphnia is a genus; it is a small crustacean that lives in fresh water. The body of the daphnia is visible and its internal organs are clearly seen thus it was chosen for this exercise. The
3rd create wells: put a comb template in middle of the tray; wait until the mixture becomes solid. After,