Which sequence of events gives rise to flaccid guard cells and stomatal closure at night?

Question

Which sequence of events gives rise to flaccid guard cells and stomatal closure at night? (A) Low [Glucose] ⇒ low osmotic pressure ⇒ low pH ⇒ high pCO2 (B) Low pH ⇒ high pCO2 ⇒ low [Glucose] ⇒ low osmotic pressure (C) Low osmotic pressure ⇒ high pCO2 ⇒ low pH ⇒ low [Glucose] (D) High pCO2 ⇒ low pH ⇒ low [Glucose] ⇒ low osmotic pressure

Tardigrade Admin · Accepted Answer

Stomata are open during the day and close during night. There are certain factors affecting stomatal movement.

Stomatal opening during day	Stomatal closure during night
Rise in pH	Low pH
Low $pC O_{2}$	High $pC O_{2}$
High humidity	Dry environment
High osmotic pressure	Low osmotic pressure
High glucose	Low glucose

Q. Which sequence of events gives rise to flaccid guard cells and stomatal closure at night?

Low [Glucose] $\Rightarrow$ low osmotic pressure $\Rightarrow$ low pH $\Rightarrow$ high $pC O_{2}$

Low $p H \Rightarrow$ high $pC O_{2} \Rightarrow$ low [Glucose] $\Rightarrow$ low osmotic pressure

Low osmotic pressure $\Rightarrow hi g h pC O_{2} \Rightarrow l o wp H \Rightarrow$ low [Glucose]

High $pC O_{2} \Rightarrow$ low pH $\Rightarrow$ low [Glucose] $\Rightarrow$ low osmotic pressure

Q. Which sequence of events gives rise to flaccid guard cells and stomatal closure at night?

Low [Glucose] ⇒ low osmotic pressure ⇒ low pH ⇒ high pCO2​

Low pH⇒ high pCO2​⇒ low [Glucose] ⇒ low osmotic pressure

Low osmotic pressure ⇒highpCO2​⇒lowpH⇒ low [Glucose]

High pCO2​⇒ low pH ⇒ low [Glucose] ⇒ low osmotic pressure

Low [Glucose] $\Rightarrow$ low osmotic pressure $\Rightarrow$ low pH $\Rightarrow$ high $pC O_{2}$

Low $p H \Rightarrow$ high $pC O_{2} \Rightarrow$ low [Glucose] $\Rightarrow$ low osmotic pressure

Low osmotic pressure $\Rightarrow hi g h pC O_{2} \Rightarrow l o wp H \Rightarrow$ low [Glucose]

High $pC O_{2} \Rightarrow$ low pH $\Rightarrow$ low [Glucose] $\Rightarrow$ low osmotic pressure