Essay Color Key

Free Essays
Unrated Essays
Better Essays
Stronger Essays
Powerful Essays
Term Papers
Research Papers





Photosynthesis

Rate This Paper:

Length: 1022 words (2.9 double-spaced pages)
Rating: Red (FREE)      
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Photosynthesis



Light Intensity
===============

Aim: The aim of this investigation is to investigate how light
intensity affects the rate of photosynthesis.

Plan:

I plan to put a pondweed into a beaker filled with 400 ml of water and
100 ml of sodium hydrogen carbonate. Then shine a lamp 15 cm away from
the beaker onto it and I will count the number of bubbles for 2
minutes. After recording results will move the lamp away 5 cm further
away and start ton record again for 2 minutes. I'm going to do this
until the lamp is 35 cm away from the lamp.

Variables:

Light Intensity - The plant needs light for photosynthesis to occur,
so if the light intensity were increased the rate of photosynthesis
would increase as well because the chlorophyll would be able to absorb
more light.

Wavelength (color of light)- The pondweed cannot absorb green light
because the chlorophyll itself is green and it reflects the green
light (reason you it is green). But it can absorb other colors.

Concentration of CO2 (Carbon Dioxide) - The plant needs Carbon dioxide
so that photosynthesis can occur. The higher the concentration of
carbon dioxide the more it has so that the light can convert it into
sugar.

Temperature - The temperature affects the rate of photosynthesis
because the temperature affects the movement/speed of molecules and
the reactions worked by enzymes. If the temperature is too hot the
enzymes would de-nature

Amount of Sodium Hydrogen Carbonate - The amount of sodium hydrogen
carbonate affects the rate of photosynthesis because it provides the
carbon dioxide for the pondweed in the water.

Experimental Variable:

The variable I am going to do is light intensity and the distance
between the light source and the pondweed.


Prediction:

I predict as the light source is moved further away from the pondweed,
the rate of photosynthesis would decline. This is because the light
intensity of the light from the light source should decrease because
the distance is getting larger and the plant would have less light to
absorb.

Hypothesis:

Equipment:

The following equipment was used in the investigation:

· Beaker (600ml)

· Meter Ruler

· Thermometer

· Pond weed

· Tile

· Cutter

· Measuring Cylinder

· Lamp

· Test Tube

· Funnel

· Goggles

· Stop Watch

· Transparent Plastic

· Tweezers

· Sodium Hydrogen Carbonate (NaHcl)

Fair Test:

To obtain a fair test in the investigation I am going to have:

Same amount of time - The same amount of time so that the results are
fair

Same water temperature - The temperature of the water stays the same
or the molecules or enzymes do not de-nature. The temperature also
affects the speed and movement of the enzymes and the number of
bubbles will increase due to the increase in temperature.

Same Volume of water (400ml) and sodium hydrogen carbonate (100ml) -
The amount of Sodium Hydrogen Carbonate affects the rate of
photosynthesis so if there was a different amount of it the rate would
be different as well.

Same light source - If a different light source was used each time the
light source the light bulb might consume more watts because it is a
different light bulb. This will cause the rate of photosynthesis to
change.

Same Venue - If I were in a different venue the light from the sun
would be different, so this might affect the rate.

Same Pondweed - If the pondweed were larger there would be more
surface area with chlorophyll to absorb more light therefore
increasing the rate of photosynthesis.

Method:

1. Collect all the equipment needed

2. Fill beaker with490ml of water and 10 ml of sodium hydrogen
carbonate (NaHcl)

3. Cut end of pond weed with cutter at a 45 degree angle

4. Set up equipment as shown in diagram on the next page

5. Move the lamp 15 cm from the beaker

6. Place transparent glass in front of the lamp

7. Wear safety goggles to protect from

8. Switch on lamp and start the stop watch

9. Start counting the bubbles for 2 minutes

10. Record results in a appropriate table

11. Move lamp 5 cm more away from the beaker

12. Repeat steps 8 - 11 until lamp is 35 cm from the beaker

13. Repeat the experiment 3 times after finished the first one

Results:

18th February 2003

Distance (cm)

Time (Minutes)

Number Of Bubbles

Water Temperature (degrees centigrade)

15

2

270

27

20

2

243

27

25

2

217

27

30

2

206

27

35

2

203

27

18th February 2003

Distance (cm)

Time (Minutes)

Number Of Bubbles

Water Temperature (degrees centigrade)

15

2

400

27

20

2

303

27

25

2

357

27

30

2

291

27

35

2

261

27

20th February 2003

Distance (cm)

Time (Minutes)

Number Of Bubbles

Water Temperature (degrees centigrade)

15

2

40

28.5

20

2

31

28.5

25

2

22

28.5

30

2

27

28.5

35

2

29

28.5

20th February 2003

Distance (cm)

Time (Minutes)

Number Of Bubbles

Water Temperature (degrees centigrade)

15

2

52

28.5

20

2

46

28.5

25

2

40

28.5

30

2

36

28.5

35

2

33

28.5

[IMAGE]Diagram above shows us that as the lamp is moved further away
from the beaker the rate of which photosynthesis occurs slows down.

Conclusion:

In the results, it shows us that as the distance between the beaker
and lamp was amplified the number of bubbles coming out every two
minutes slowly declined. This means as the lamp was moved further away
the rate of which photosynthesis was occurring was decreasing. This is
because the light intensity was also being reduced as the lamp was
moved further away, therefore there was less light for the pondweed to
absorb.

In the 3rd and 4th test the results are lower than the 1st and 2nd
ones because maybe when I was doing the experiment the time of the day
was different and there was less light coming through the windows from
the sun. Or maybe I waited for a shorter time for the pondweed to heat
up and there was less oxygen stored in the plant that hadn't come out
yet.

Evaluation:

I think the experiment was generally successful because the result
that happened is what I predicted in my prediction.

Few things affected my results though.

Firstly the temperature was different, this may have happened because
the room temperature was different because maybe the air-conditioner
was on. The temperature of the water collected could have been a
different temperature. It could have been both of these factors that
affected the temperature of the water. To improve my experiment I
could have done the experiment in the same room with the same
environment.

I didn't measure the light intensity so it was not possible for me to
know if the light intensity was different. I should have u a light
meter to measure the intensity of the light.

I cannot approximately tell if the rate of photosynthesis is actually
changing because I only count the bubbles without noticing the sizes
of them so if the rate of which the bubbles are increasing, it might
not actually be increasing. Just that they are smaller ones than
before, therefore there are more.

There could have been human errors in counting the bubbles because I
was counting large numbers of bubbles in a long period.

How to Cite this Page

MLA Citation:
"Photosynthesis." 123HelpMe.com. 20 Apr 2014
    <http://www.123HelpMe.com/view.asp?id=122341>.




Related Searches





Important Note: If you'd like to save a copy of the paper on your computer, you can COPY and PASTE it into your word processor. Please, follow these steps to do that in Windows:

1. Select the text of the paper with the mouse and press Ctrl+C.
2. Open your word processor and press Ctrl+V.

Company's Liability

123HelpMe.com (the "Web Site") is produced by the "Company". The contents of this Web Site, such as text, graphics, images, audio, video and all other material ("Material"), are protected by copyright under both United States and foreign laws. The Company makes no representations about the accuracy, reliability, completeness, or timeliness of the Material or about the results to be obtained from using the Material. You expressly agree that any use of the Material is entirely at your own risk. Most of the Material on the Web Site is provided and maintained by third parties. This third party Material may not be screened by the Company prior to its inclusion on the Web Site. You expressly agree that the Company is not liable or responsible for any defamatory, offensive, or illegal conduct of other subscribers or third parties.

The Materials are provided on an as-is basis without warranty express or implied. The Company and its suppliers and affiliates disclaim all warranties, including the warranty of non-infringement of proprietary or third party rights, and the warranty of fitness for a particular purpose. The Company and its suppliers make no warranties as to the accuracy, reliability, completeness, or timeliness of the material, services, text, graphics and links.

For a complete statement of the Terms of Service, please see our website. By obtaining these materials you agree to abide by the terms herein, by our Terms of Service as posted on the website and any and all alterations, revisions and amendments thereto.



Return to 123HelpMe.com

Copyright © 2000-2013 123HelpMe.com. All rights reserved. Terms of Service