Кембрижийн шинжлэх ухааны уралдаан

Кембрижийн шинжлэх ухааны уралдаан

Шинжлэх ухааны сонирхолтой туршилтуудаар дэлхийн 145 улсын сурагчидтай өрсөлдөнө.

Cambridge International is pleased to offer an exciting competition for Cambridge IGCSE and O Level learners. We want to give learners the opportunity to develop their passion for science through practical work, investigating topics of interest and using the scientific method. We also want to promote the attributes of a Cambridge learner through collaboration and communication, promoting innovation and creativity.


Cambridge Upper Secondary Science Competition

Innovative ideas


Supervisor Namsrai J
Team members: Dulguun O, Alex T, Gundbilgun G, Injir B, Munkhdelger M, Nomin S 


Photosynthesis: synthesis of chemical compounds with the aid of radiant energy and especially light; especially: formation of carbohydrates from carbon dioxide and a source of hydrogen (such as water) in the chlorophyll- containing cells (as of green plants) exposed to light. In this experiment:

  1. To measure the effect of sewage water treatment’s partial purified water photosynthesis of water plant, we choose washing liquid. 
  2. In 2014, Central Geological Laboratory has certified that the capacity of sewage water treatment is 50.7-52.8%. And it pollutes some part of Tuul River to lose its oxygen system to 0.05-2.79 mg/l which is the main reason of this project.

We made an experiment to identify the possible effects of petrol contained in those cars that had drowned in Khuvsgul.
In the last 50 years, almost 40 trucks and other types of vehicles have been reported to be sunk. For example, in 1996, two cars loading ten tons of fuel crashed and in 2007 congealed the fuel that froze on its motor of the ship Dubovski that sunk in its parking in Khankh province.
From this, you can see that we can pollute 381 square kilometres of lake water with at least ten thousand litres of fuel. 

  1. The Elodie (aquatic plant) in the beaker, with a layer of oil on the surface and washing liquid will not be able to perform photosynthesis and will stop producing oxygen.
  2. The Elodie’s (water plant) in the beaker with a layer of oil stopped producing oxygen after one day, while the plant in the beaker with washing liquid stopped producing oxygen even after 2 hours 30 minutes. So the plant in the beaker with pure water continued to produce oxygen even after two day.

The hypothesis the plant in the beaker with a layer of engine oil on the surface and washing liquid will not be able to perform photosynthesis and stop producing oxygen has been proven to be true.
If photosynthesis of green plants stops, biological product of environment will decrease. Furthermore biodiversity will be in danger (Tsendeehvv Ts, 2018)
From the results of the experiments, it shows that the toxic chemical substances in the incompletely treated water repress the photosynthesis of plants, which shows that river Tuul’s ecosystem could be highly damaged. So improving the working capacity and ability of the sewage water treatment is an important step to protect the river Tuul. Additionally we consider that, the action of washing cars and clothes in the river must be restricted.
Also it has been prove that petrol and engine oil repress the photosynthesis. So protecting the river Khuvsgul containing 0.4% of the world’s pure water by immediately pulling out the 40 identified drowned vehicles is one of the essential duties. Saving the immeasurable resource called Khuvsgul

Further Considerations

To enhance this project, water samples from polluted rivers, lakes, etc. can be tested whether it effects on the photosynthesis of water plants or not.
Air pollution may be effective on the photosynthesis of water and land plants. So we want to carry out by this problem.