• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11
  12. 12
  13. 13
  14. 14
  15. 15

Experiment Colours of Light (Wavelength) absorbed by green plant

Extracts from this document...


NAME : Nur Amira Rozali TITLE : COLORS OF LIGHT (WAVELENGTH) ABSORBED BY GREEN PLANT DATE : 08/02/2011 INTRODUCTION Plant contains photosynthetic materials which are responsible in the photosynthesis processes. One of the materials is chloroplast. Chloroplast is actually an organelle found in plant cells and many other eukaryotic organisms. The chloroplast, in green plant, contains many pigments; a few of them are chlorophyll a and chlorophyll b, carotene and xanthophylls. All of these are natural pigments. Natural pigments1, are substances presence in animal and plant cell that produces color due to specific absorption of light and reflection of the unabsorbed light. In this experiment, the chlorophyll of the plant is going to be extracted and is centrifuged before it is tested with a set of calorimeter. Calorimeter is a device that is used to measure the absorption percentage of wavelength by a substance; in liquid state. RESEARCH QUESTION How does different green plant differ in the absorption of wavelengths? AIM To investigate the amount of absorption between two green plants (Spinach and Mustard) exposed to different range of wavelengths (440nm, 470nm, 490nm, 520nm, 550nm, 580nm, 590nm and 680nm). HYPOTHESIS The rate of absorption of between the two green plants (Mustard and spinach) is different. It is hypothesized that both spinach and mustard will have a large absorption of red and blue colour. Green is of an exception. It is also hypothesized that the mustard will have a lower absorption of green colour than that of spinach. Spinach has a greener color due to the existence of larger volume of chlorophyll than that that is available in the mustard. Hence it imposes a greener colour due to a higher reflection of green colour. VARIABLES Variables Method to control Range Independent Variable The wavelengths that are imparted on the green plant form a calorimeter Different wavelengths represents different colours are varied by using a calorimeter. ...read more.


This photosynthetic pigment is the one that reflects green colour. Two layers formed in the centrifuge tubes Two layers formed. The supernatant is at the top as it ahs a lower density than that of the debris below the centrifuge tube. Table 10: The table above shows the explanation. Graph 1: The percentage of absorption against wavelength of spinach sample Graph 2: The percentage of absorption against wavelength of mustard sample Graph 1 shows the graph of rate of photosynthesis od disk leaf against distance of the light source from the beaker. DISCUSSION a) The photosynthetic pigments are materials that are responsible for absorbing and trapping the light energy in the earlier steps of photosynthesis. One of the major pigments of photosynthetic materials is chlorophylls. Chlorophylls is a mixture of pigments that comprises of chlorophyll a, chlorophyll b and some carotenoids like B-carotene, Xantophyll and phaeophytin. However, other types of chlorophyll like chlorophyll c and bacteriochlorophyll are found in non green plant, protistans and photosyntehetic bacteria. b) The main objective of this experiment is to prove the fact that different form of plant which contains different concentration/number of photosynthetic pigments is tend to absorb different value of wavelength, hence, its different colour. Earlier hypothesis suggests that the wavelength will be absorbed by the photosynthetic pigment at a different absorption. Different wavelength which is absorbed or reflected by the photosynthetic pigments will determined the colour observed on the leaves. For example, two samples that are used in the experiment is spinach and mustard plant. In the earlier observation, it can be seen that the spinach plant is greener than that of mustard plant which a little bit light green. Hence a hypothesis is formed that the photosynthetic pigments in the spinach plant is able to absorb less amount of green wavelength compared to that of a mustard plant. Hence, more green wavelengths will be reflected by the pigments in spinach plant than that in mustard. ...read more.


(+0.01) Standard Solution Mustard sample T1 T2 T3 440 0.00 2.00 2.00 2.00 470 0.00 1.33 2.00 2.00 490 0.00 0.75 1.95 2.00 520 0.00 -0.30 1.44 1.87 550 0.00 0.58 1.55 1.88 580 0.00 -0.29 1.81 2.00 590 0.00 1.34 2.00 2.00 680 0.00 0.43 1.87 1.91 Wavelength (nm) Average percentage of absorbance of wavelength by mustard sample (With respect to standard solution at 0.00 absorbance) 440 [2.00+2.00+2.00]/3 = 2.00 470 [1.33+2.00+2.00]/3 = 1.80 490 [0.75+1.95+2.00]/3 = 1.60 520 [-0.30+1.44+1.87]/3 = 1.00 550 [0.58+1.55+1.88]/3 = 1.34 580 [-0.29+1.81+2.00]/3 = 1.17 590 [1.34+2.00+2.00]/3 = 1.78 680 [0.43+1.87+1.91]/3 = 1.40 Table 7: Average percentage of absorption by spinach sample (%) The calculation for the standard deviation for the average percentage of absorbance of wavelengths by both spinach and mustard samples (With respect to standard solution at 0.00 absorbance) is calculated by using the following formula: Standard deviation = Where, x: Percentage Absorbance of the samples (Spinach or mustard) exposed in different wavelengths Average percentage of absorbance of wavelengths by samples (Spinach or mustard) (with respect to standard solution at 0.00 absorbance) N: Number of trial Wavelength (nm) Average percentage absorbance of wavelength by spinach sample (With respect to standard solution at 0.00 absorbance) Standard deviation of the average percentage absorbance of wavelength 440 2.00 0.000 470 1.91 0.042 490 0.96 0.12 520 0.71 0.062 550 0.47 0.31 580 1.00 0.20 590 1.16 0.03 680 1.39 0.045 Table 8: The table above shows the standard deviation of the average percentage of absorption of wavelength of spinach Wavelength (nm) Average percentage absorbance of wavelength by mustard sample (With respect to standard solution at 0.00 absorbance) Standard deviation of the average percentage absorbance of wavelength 440 2.00 0.00 470 1.80 0.40 490 1.60 0.71 520 1.00 1.15 550 1.34 0.68 580 1.17 1.27 590 1.78 0.40 680 1.40 0.84 Table 9: The table above shows the standard deviation of the average percentage of absorption of wavelength of mustard. REFERENCE 1. Biology Oxford, Standard and Higher Level, Andrew Allot: Topic; Photosynthesis 2. Http://wikipedia_chlorophyll.com 3. Biology for IB Diploma, Hodder Education, CJ Clegg, page 288 ?? ?? ?? ?? ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Biology essays

  1. DNA Strawberry Extraction Lap

    Also, some human genes may be manipulated to change things such as lung capacity, brain capacity and muscle mass to make a "super" human. 10) Provide two examples of plant genes that already modified and the reasons for the modification.

  2. Environmental Factors affecting plant growth

    seem to be developing very well without any problems. The stem and root growth is very good and the leaves seem very healthy and were bright green. But the plants for the rest of the treatments (100%s, 75%s and 50%s)

  1. Biology Lab - frequency of cell division in animal and plant cell

    All students in the class recorded the data which was needed to calculate the field of view, drawing of fit and calculated the magnification. Percentage of cells division and the standard of deviation were later calculated by the individuals. Qualitative Description: The onion root tip cells were green and rectangular and fixed shape.

  2. Osmosis Experiment. This experiment is to consider how salinity influences osmosis in potato cells.

    Pearl-white Very clear water Very firm and slippery 0.2% Pearl-white A bit cloudy under the potato cube but clear above it Firm and not slippery Short fur-like coat around the whole piece of potato 0.4% Marble-white A bit cloudy around the piece of potato Firm and not slippery Short fur-like

  1. Biology- Extended essay. For this research, I investigated the effects of DDT and ...

    First minute Second minute Third minute Fourth minute Fifth minute CONTROL A 149 148 145 150 146 147.60 2.07 B 150 148 147 146 148 147.80 1.48 C 146 145 148 144 147 146.00 147.08 1.58 2.13 D 151

  2. What is the effect of increasing pH concentration (pH 3, 4, 5, 6 and ...

    growth of seeds and that a neutral pH helps in the germination of seeds faster and better. Evaluation The result obtained by conducting the above experiment is accurate due to the following reasons:- * The spacing between the seeds in the Petri dish was the same.

  1. Plan for an experiment - How does temperature affect the rate of photosynthesis?

    Elodea 3 Between 5 - 35°C, the same Elodea plant will be used. However, after 30 - 35°C, if no oxygen bubbles are produced, the spare elodea plants may be used, as it can be assumed the low –no production of oxygen is due to the denaturation of the enzymes within the plant.

  2. Biology lab - testing the effects of light intensity on photosynthesis.

    Place test tube rack with test tubes 1 and 2 in light source. 9. Have two team members count the number of bubbles produced in each test tube for 5 minutes. 10. At the same time, two team members will be counting the bubbles produced in test tube 3 and 4 for 5 minutes.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work