Investigating Photosyntesis in Pond Weed
Aim:
The aim of this experiment is to find out what effects the amount of
photosynthesis happening in a pond weed.
Introduction:
A piece of pondweed will be cut and placed into a test tube containing
water and sodium hydrogen carbonate, which is placed inside a beaker
containing water. A lamp will be shined on to the pondweed and the
amount of bubbles released from the plant will be counted. The lamp
will be adjusted to different distances from the plant to try and
obtain different results. The amount of bubbles will be counted for a
period of one minute. The temperature of the water would be recorded
at the start and end of the minute.
Photosynthesis Equation:
[IMAGE]6CO2 + 12H2O SUNLIGHT C6H12O6 + 6H2O + 6O2
Preliminary Work:
The problems that arose whilst doing the preliminary experiment was
that too much sodium hydrogen carbonate was placed inside of the test
tube and all the water had turned cloudy so it was impossible to count
the amount of bubbles. Also the beaker was placed too far away from
the light which meant that the light wasn't reaching the beaker. The
preliminary experiments showed that the closer the light is to the
beaker the more bubbles appear.
Distance (cm)
Start Temp (ºC)
End Temp (ºC)
Amount of bubbles in 1 minute
10
32
29
32
20
30
28
22
30
29
28
13
40
29
29
6
50
28
28
2
60
27
28
2
Fair Test:
The experiment will be made fair by adding the same amount of sodium
hydrogen carbonate each time so that this will not change the amount
of bubbles for the change of distance. Also the same lamp will be used
First, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder. This water was then poured into the styrofoam cup that will be used to gather the hot water later. The water level was then marked using a pen on the inside of the cup. The water was then dumped out, and the cup was dried. Next, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder, and the fish tank thermometer was placed in the water. Once the temperature was stabilizing in the graduated cylinder, the marked styrofoam cup was filled to the mark with hot water. Quickly, the temperature of the regular water was recorded immediately before it was poured into the styrofoam cup. The regular/hot water was mixed for a couple seconds, and the fish tank thermometer was then submerged into the water. After approximately 30 seconds, the temperature of the mixture leveled out, and was recorded. This was repeated three
Firstly, when testing temperatures at 30°C and 40°C, the water was. sometimes heated more than needed, so I had to wait until it cooled. down to the required temperature. To avoid this happening, a. thermostatic water bath could have been used, because I could set it. to the required temperature.
In this experiment I will investigate the affect in which the light intensity will have on a plants photosynthesis process. This will be done by measuring the bubbles of oxygen and having a bulb for the light intensity variable.
As the light is increased so would the rate of photosynthesis. Apparatus: boiling tube, 250ml beaker, bench lamp, ruler, sodium
I added ½ tablespoon of baking soda to 4 cups of water. I added a small drop of liquid soap to the water and stirred to mix. I used the end of a straw and cut out 20 circles of spinach leaves. I pulled the plunger completely out of the syringe and put the leaf circles into the syringe. Next I pushed the plunger back in. I used the syringe to suck up the baking soda water until the syringe was about ¼ full of liquid. I placed my finger over the end of the syringe and pulled back on the plunger as far as I could without pulling the plunger out. I repeated this step three times. All the leaf circles sunk to the bottom of the liquid. I placed the spinach into a clear glass with about 2 inches of baking soda solution. I blocked out all light. I set the lamp with a compact florescent light bulb. I placed the glass in front of the lamp. I counted the number of circles that floated after each minute for 20 minutes (positive control). I created a negative control by not placing compact florescent light bulb and not placing the glass in front of the lamp. I counted the number of circles that are floating. I repeated the experiment with fresh circles and used regular water plus soap for all steps instead of baking soda and soa...
The Effect of Light Intensity on the Rate of Oxygen Production in a Plant While Photosynthesis is Taking Place
An Analysis and Evaluation of Data from Photosynthesis Experiments Graph analysis This is my analysis for the investigation in to the affect of light intensity on the rate of photosynthesis to the Canadian pondweed, elodea. In the results the pattern is that when the light intensity is higher the readings are generally higher. On the graph the less the light intensity the lower the gradient of the curve. the equation for the photosynthesis process is; CO2 + 2H2O + Light Energy = =
The Effect of Wavelength on Photosynthesis Rate Aim: To be able to To investigate how different wavelengths (colors) of light affect the photosynthetic rate of the synthetic. I will use a pant that is a pond weed called elodea. I will measure the rate of photosynthesis by measuring the amount of o2 given off in bubbles per minute from the elodea. I will do this by placing the Elodea in a test tube with sodium hydrogen. carbonate then I will vary the light wavelength (color) using colored.
Once the time’ is set, the breakers are put into their corresponding places for an hour. The purpose of giving the Elodea an hour is to allow the plant to begin photosynthesis. Once an hour has passed, both beakers were removed from their positions and the Elodea were returned to the tank. At this point of the experiment, three drops of phenolphthalein were added into each of the three beakers. Phenolphthalein help determine measurement of the carbon dioxide reproduction in order for it do photosynthesis and 0.02mL of NaOH drops are included into "Elodea with 20 salt drops" until the solution turns into a shade of dark pink; recording the drop to better understand the carbon dioxide production levels of photosynthesis and respiration done by the Elodea (Walsh and Wostl
Two electrical wires * Stopwatch * Thermometer Method I put a piece of Elodea Canadensis (pond weed) in a test tube and covered it with water. The test tube was then placed in a beaker with a thermometer so that the water stayed the same temperature, this was then placed in a cardboard box with a bulb attached to a voltmeter by the electrical wires so that I could concentrate how much light the plant got. I varied the voltage (intensity) of the bulb and counted how many bubbles of oxygen were created at each voltage in one minute. I tested each voltage three times for accuracy for a minute each time. Results Preliminary Experiment Amount of bubbles Light intensity (lux)
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.
Plant pigments are molecules which reflect one color and absorb the rest. Plants use this light for photosynthesis which is the process by which plants make their food for energy. The reason for there being more than one pigment in a leaf is because each pigment can only absorb certain wavelengths of light, so leaves have more than one so they can absorb more light for photosynthesis. The pigments used for photosynthesis are found in the thylakoid membranes. Light must pass through the leaf and into the photosynthetic pigments so it can be absorbed. This is the reason why leaves are so thin. They want light to penetrate the leaf and get into the chlorophyll so photosynthesis can occur. If the leaves were to be thick then no light
Investigating the Effect of Light Intensity on Photosynthesis in a Pondweed Aim: To investigate how the rate of photosynthesis changes at different light intensities, with a pondweed. Prediction: I predict that the oxygen bubbles will decrease when the lamp is further away from the measuring cylinder, because light intensity is a factor of photosynthesis. The plant may stop photosynthesising when the pondweed is at the furthest distance from the lamp (8cm). Without light, the plant will stop the photosynthesising process, because, light is a limited factor. However once a particular light intensity is reached the rate of photosynthesis stays constant, even if the light intensity is the greatest.
During the following lab, an aquatic plant was covered with a funnel and was placed underwater inside a beaker, with a graduated cylinder (submerged in water) was placed over the neck of the funnel. This lab tested out which source of light which is the independent variable would allow the aquatic plant to produce the most bubbles (dependent variable) and photosynthesize the fastest. This is clearly displayed because when photosynthesis is produced underwater it appears in the form of bubbles inside the water. These bubbles will travel up through the funnel and displace the water in the graduated cylinder. The dependent variable was tested by placing the four, 5cm aquatic plants in the beakers directly in front of the sources of light and observing how many bubbles were produced within the period of 10 minutes and how much water was displaced by the oxygen bubbles. The beaker in front of the light source with the most bubbles produced and with the most displaced water performed photosynthesis faster than all the other light sources. The sources of light used for this lab were sunlight, florescent, red, and yellow lamp lights, and
An Experiment to Investigate the Effect of Light Intensity on the Rate of Photosynthesis. Introduction Photosynthetics take place in the chloroplasts of green plant cells. It can produce simple sugars using carbon dioxide and water causing the release of sugar and oxygen. The chemical equation of photosynthesis is: [ IMAGE ] 6CO 2 + 6H20 C 6 H12 O 6 + 6O2 It has been proven many times that plants need light to be able to photosynthesize, so you can say that without light the plant would neither photosynthesize nor survive.