If a nail is hammered in the bark of tree at height 4 m, after ten years the height of tree is doubled. Then the height of nail will be:

• 4 m

• 8 m

• 16 m

• 10 m

The transition to flowering in plants requires

• Growth of plants under long – day conditions

• Growth of plants under short‐day conditions

• Reprogramming of the shoot apical meristem

• Synthesis of the flowering hormone florigen

Both halophytes and glycophytes compartmentalize cytotoxic ions into the intracellular compartment or actively pump them out of the cell to the apoplasts with the help of membrane transport proteins. Among these, the Na⁺‐H⁺ antiporter, NHX1, is localized in

• The plasma membrane

• Chloroplast (inner envelope)

• Mitochondria (outer membrane)

• Tonoplast

The photoreceptor commonly involved in light entrainment of the biological clock in flies, moulds and plants is

• Phytochrome

• Rhodopsin

• Carotenoid

• Cryptochrome

Most abundant intracellular ion in plants is:

• Iron

• Calcium

• Potassium

• Zinc

S-adenosyl methionine is a precursor of which plant hormone?

• Abscisic acid

• Auxin

• Ethylene

• Cytokinin

The one of the most widely used herbicides methyl viologens interfere photosynthesis of higher plants. They are responsible for

• Evolution of more oxygen

• Dissipation of proto gradient across thylakoid membrane

• Inhibition of flow of electron from PS II to PS I

• Transfer of electrobs from PS I to molecular oxygen

8.

Which would be the result of mutation in genes responsible for radial patterning in roots of higher plants?

• No apical root formation

• Root hair will fail to develop

• Variation in number and position of cell in vascular system

• Roots will be positively geotrophic

Among the following which gene product migrates from leaves to shoot meristem during transition of shoot meristem into floral meristem?

• Flowering locus T

• Flowering locus D

• Leafy

• Apetala 1

Which group of algae is believed to be most closely related to higher plants?

• Charophyceae   

• Chlorophyceae 

• Rhodophyceae

• Pheophyceae