141.

Which of the following facilitates opening of stomatal aperture?

• Contraction of outer wall of guard cells

• Decrease in turgidity of guard cells

• Radial orientation of cellulose microfibrils in the cell wall of guard cells

• Radial orientation of cellulose microfibrils in the cell wall of guard cells

The water potential of pure water is

• Zero

• Less than zero

• More than zero but less than one

• More than zero but less than one

Which of the following elements is responsible for maintaining turgor in cells?

• Magnesium

• Sodium

• Calcium

• Potassium

Stomatal movement is not affected by

• Temperature

• Light

• CO₂ concentration

• O₂ concentration

Some functions of the nutrient element are given below

1. Important constituent of proteins involved in ETS.
2. Activator of catalase.
3. Important constituent of cytochrome
4. Essential for chlorophyll synthesis

The concerned nutrient is

• Cu

• Fe

• Ca

• Mo

Tyloses an outgrowth from ray or axial parenchyma cell into the lumen of a vessel, which partially or completely blocks the cavity are present in

• Periderm

• Heart wood

• Sap wood

• Secondary cortex

In which form does the food is transported in plants?

• Sucrose

• Fructose

• Glucose

• Lactose

In plants, water supply is due to

• osmosis

• imbibition

• guttation

• adhesion force

Most accepted theory for ascent of sap is

• capillary theory

• root pressure theory

• pulsation theory

• transpiration pull

Which of the following theory gives the latest explanation for the closure of stomata?

• ABA theory

• Munch Theory

• Starch glucose theory

• Active K⁺ transport theory