Today i will share you how to learn one of experiment about Sach Experiment. This practice is a variation of practicum photosynthesis. In this lab we will prove that photosynthesis produces starch. This practicum design is often called the Sach experiment. This practice has also proven that photosynthesis also produces oxygen.
This practice aims to prove that the leaves require light for photosynthesis to produce starch.
Tools and materials
- Aluminum foil
- Paper clips
- Beaker glass
- Test tube
- Scissor
- Bunsen
- Tripod
- Alcohol
- Iodine
- Leafy plants in pots
Prosedures Steps :
- Put the leafy plants in the dark around 2 - 3 days.
- After that choose a leaf width, cover some leaf surface with aluminum foil. Use clip to pinch it.
- Place the pot in a spot that is exposed to direct sunlight for about 5 hours.
- Complete the leaf that has been covered with the aluminum foil and do the test with lugol.
- How to do the starch / lugol test:
- Boil the leaves in boiling water for a few minutes until withered
- Boil the leaves in hot alcohol to dissolve the chlorophyll (see figure)
- Wash leaves under running water
- Drop leaves with lugol / iodine solution and observe the color change. Look the picture below:
Step 1
Step 2
Step 3
Step 4
Source of Pictures
The results of the Test Sach experiment to prove the photosynthesis resulted in the starch After you do this iodine test the result is roughly like this:
)# Explaination 
)
>Left: only the chlorophyll part that carries photosynthesis and produces the starch. Right: the non-chlorophyll part does not carry photosynthesis so that no starch is formed.
Photosynthesis produces starch
Left: blackish-black color contains a lot of starch. Right: pale brown color does not contain starch
Conclusion
The process of photosynthesis produces starch. This can be known when the surface of the leaf that is exposed to light drops its iodine solution the color turns to a blackish black (iodine + amylum -> blackish black). Parts of the leaves that are not exposed to light do not do photosynthesis, so do not form the starch. When the iodine drops the color is pale.
Sources :
Starch Experiment Teory
Pictures
Photosynthesis
Thanks a lot sharing a scientific knowledge.
I still remember i had once did a similar experiment when i was in primary school, where i boil off the chlorophyll and use a tooth brush to rip off the epithelial cell. What remain was the xylem and branches as a beatiful bookmark :))
Yes this experiment is usually done by students when primary school. Students look very enthusiastic when doing this experiment. And many students are trying to use other leaves with their friends at home. Maybe your memory will also re-repeat time studying in school first. May you always be filled with memories of knowledge that has been obtained. :))