Some plants release oxygen in night! Truth or Myth

So we all have heard some of the trees release oxygen even in the night. But is it really a truth or a myth. Lets decipher this fact scientifically but in short.    

 

 Some plants which releases oxygen in night.

Tulsi(Ocimum tenuiflorum)

Peepal(Ficus religiosa)

Snake Plant(Sansevieria trifasciata)

 

The differences in climatic conditions and ecosystems have resulted in different types of photosynthesis in plants.  The three types photosynthesis are C3, C4 and CAM photosynthesis. 

But we will talk about CAM as it happens in night & it is the reason given by every one supporting oxygen at night fact.

 

This type of photosynthesis is most common in desert plants where water is at a premium.  

 

The most important benefit of CAM to the plant is the ability to leave most leaf stomata closed during the day thus saving 97% of water it absorbs.

But from where does it gets CO2 in morning if stomata is closed?????

 

 

 

In CAM photosynthesis, CO2 is taken up only at night.In the morning, sunlight driving the light reactions allows the stored carbon to be combined into sugars.

A common misconception is "Photosynthesis is used to generate oxygen"

•  Photosynthesis is the process by which green plants, algae and some forms of bacteria use energy from sunlight to convert carbon dioxide and water into glucose.

CONSLUSION:

Yes there are some plants which absorb CO2 even in night but they release oxygen only during the day

But definitely they reduce CO2 level in the night.

 

For better explanation regarding process of CAM refer following articles & Diagrams.

https://en.wikipedia.org/wiki/Crassulacean_acid_metabolism

http://photosynthesiseducation.com/photosynthesis-in-plants/

http://w3.marietta.edu/~biol/biomes/photosynthesis.htm