Question

leaves of a healthy potted plant were coated with vaseline to block the stomata. will this plany remain healthy for long time ? state three reason for your answer.

Answer 1

1.Plant uptakes CO2 in daytime to produce it own food . By closing stomata it will not perform Photosynthesis anymore and hence will die out of starvation.
2.transpiration will not occur.
3.gaseous exchange stops i.e taking in of co2 and releasing o2.

Note:this answer is only based on my own knowledge.
For better ans u can approach someone else.

Answer 2

the plant will no longer remain healthy. 
1)vaseline block the stomata so there will be no intake of co2.  
2)it will completely block the stomata even after we remove it .
3)it also stops the plant for recieving  heat and plant will die.