P20. The chloroplast and the photosynthesis

INTRODUCTION:

We will investigate how it affects the distance of the light relative to a algae in her photosynthesi.

OBJECTIVES:

• Relate the light intensity with the photosynthesis process.
• Measure the rate of photosyntesis.
• Identify the products of the process and the variables that can affect it. 

MATERIALS:

• Algae 
• Beaker (600mL)
• Test tube
• Funnel
• Sodium bicarbonate solution (10%)
• Light source
• Metric Ruler

PROCEDURE:

1. Take a big beaker (you have to place a funnel inside)

2. Every group will place a spring of algae (underwater) under a clear funnel inside the beaker.     Place the wide end of the funnel over the algae as the image you have belw. The funnel is         raised off the bottom on pieces of blue-tack to allow unhampered diffusion of CO2 to Elodea. 

3. Fill the beaker with the sodium bicarbonate solution; the algae and the funnel should be             completely under the solution.

4. Fill a test tube with the solution. Place your thumb over the end of the test tube.Turn the test     tube upside down, taking care that no air enters.

5. Mark the level of solution on the surface of the test tube.

6. Place your preapartion close to a light source. Each group will place its preparation in a             different distance from the light source. 
    5cm, 10cm, 20cm, 25cm and one with no light source.

7. Measure the temperature.

8. Leave this preparation 1 hour and a half. After this time we measure the difference of gas accumulation on the top of the test tube. 

Conclusions and coments:

The comclusions are: