The Effect of Light Intensity and Temperature on the Rate of Photosynthesis
Aim
The aim of my experiment is to determine whether intensity of light
and temperature would affect the rate of photosynthesis in a plant. To
do this, I will place a piece of pondweed in varying light intensities
and temperatures, and observe the amount of oxygen being given off. I
am using pondweed because of its unusual quality of giving off bubbles
of gas from a cut end, when placed in water.
Introduction
Photosynthesis occurs only in the presence of light, and takes place
in the chloroplasts of green plant cells. Photosynthesis can be
defined as the production of simple sugars from carbon dioxide and
water causing the release of sugar and oxygen.
The chemical equation for photosynthesis can be expressed as:
(light)
6CO2 + 6H2O-------------- C6H12O6 + 6O2
(In the presence of chlorophyll)
The word equation:
Carbon dioxide + Water------------ Glucose + Oxygen
The fact that all plants need light in order to photosynthesise has
been proven many times in experiments, and so it is possible to say
that without light, the plant would die. The reason that light
intensity does affect the rate of photosynthesis is because light is
the source of energy which, falls on the chloroplasts in a leaf and is
trapped by the chlorophyll, which then makes the energy available for
chemical reactions in the plant. Thus, as the amount of sunlight, or
in this case light from a bulb, falls on the plant, more energy is
absorbed, so more energy is available for the chemical reactions, and
so more photosynthesis takes place in a given time.
The...
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...ary the amount of CO2. The plant would be
kept at a constant distance from the lamp and a constant volume of
water would be added to the sodium hydrogen carbonate. Another
experiment using almost identical apparatus would be to vary the color
of the light the plant absorbs. Using translucent color filters in
front the lamps could vary this. Since light wave length has already
been identified as a variable of photosynthesis, it would be
interesting to actually test it. The only problem of this experiment
is that there is no way to define or "measure" the color of light.
Wave length would be a solution but this cannot be measured with
available equipment. We only have a general idea of how to class
colors. Because of this, the colored light experiment should not be
taken as seriously as light intensity or carbon dioxide.
The majority of life on Earth depends on photosynthesis for food and oxygen. Photosynthesis is the conversion of carbon dioxide and water into carbohydrates and oxygen using the sun’s light energy (Campbell, 1996). This process consists of two parts the light reactions and the Calvin cycle (Campbell, 1996). During the light reactions is when the sun’s energy is converted into ATP and NADPH, which is chemical energy (Campbell, 1996). This process occurs in the chloroplasts of plants cell. Within the chloroplasts are multiple photosynthetic pigments that absorb light from the sun (Campbell, 1996).
at the small end of the axis to see a more reliable pattern. I could
This shows that there could be three variables in this experiment, carbon dioxide, water and light energy. So in our case the variable light energy (light intensity) will be used. The equation also shows that if there is more light energy then more glucose and oxygen will be produced.
The high rate of absorbance change in blue light in the chloroplast samples (Figure 1) can be attributed to its short wavelength that provides a high potential energy. A high rate of absorbance change is also observed in red light in the chloroplast samples (Figure 1), which can be accredited to the reaction centre’s preference for a wavelength of 680nm and 700nm – both of which fall within the red light range (Halliwell, 1984). Green light showed low rates of photosynthetic activity and difference in change in absorbance at 605nm in the chloroplast samples (Figure 1) as it is only weakly absorbed by pigments, and is mostly reflected. The percentage of absorption of blue or red light by plant leaves is about 90%, in comparison to the 70–80% absorbance in green light (Terashima et al, 2009). Yet despite the high absorbance and photosynthetic activity of blue light, hypocotyl elongation was suppressed and biomass production was induced (Johkan et al, 2012), which is caused by the absorption of blue light by the accessory pigments that do not transfer the absorbed energy efficiently to the chlorophyll, instead direction some of the energy to other pathways. On the other hand, all of the red light is absorbed by chlorophyll and used efficiently, thus inducing hypocotyl elongation and the expansion in leaf area (Johkan et al, 2012).
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 = =
Investigating the Link Between Wavelength of Light and Rate of Photosynthesis PROBLEM = = = = =
To make the test fair I will use the same amount of water and the leaf
The Effect of Light Intensity on Photosynthesis Of Elodea Canadensis Introduction I wanted to find out how much the light intensity affected the Photosynthesis in Elodea Camadensa. I decided to do this by measuring the amount of oxygen created during photosynthesis. Photosynthesis is the procedure all plants go through to make food. This process uses Carbon dioxide, water and light energy. It produces Oxygen and Glucose.
The Effect of Light Intensity on the Rate of Photosynthesis in an Aquatic Plant Introduction The input variable I will be investigating is light, as light is just one of the 4 factors required in the green-plant process of photosynthesis. Photosynthesis is the process by which green-plants use sunlight, carbon dioxide, water & chlorophyll to produce their own food source. This process is also affected by the temperature surrounding the plant (the species of plant we experimented with, pond weed, photosynthesised best at around 20 degrees centigrade.) Light, temperature & CO2 are known as limiting factors, and each is as important as the next in photosynthesis. Light is the factor that is linked with chlorophyll, a green pigment stored in chloroplasts found in the palisade cells, in the upper layer of leaves.
* Count the number of bubbles seen in 1 minute which is a way of
“Photosynthesis (literally, “synthesis from light”) is a metabolic process by which the energy of sunlight is captured and used to convert carbon dioxide (CO2) and water (H2O) into carbohydrates (which is represented as a six-carbon sugar, C6H12O6) and oxygen gas (O2)” (BioPortal, n.d., p. 190).
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.
Experiment #1: The purpose of this experiment is to investigate the effects of baking soda and light intensity on the rate of photosynthesis of green spinach leave through the observation of floating disk.
Light is a very important factor in the rate of photosynthesis, in my project I am going to test that plants do need light in order to photosynthesise. It will be very interesting to see how light will influence the rate of photosynthesis in plants and what will happen if they do not get the required light in order to produce starch .