21.

Wilting of leaves at noon and their recovery toward evening is known as

• incipient wilting

• temporary wilting

• midday desiccation

• permanent wilting

Which of the following induces and promotes cell division?

• ABA

• Auxin

• Cytokinin

• Gibberellin

Artificial application of auxins like IAA, IBA and NAA to unpollinated pistils can form

• fruits with much flash

• larger fruits

• sweet fruits

• seedless fruits

Internodal elongation is stimulated by

• auxin

• cytokinin

• gibberellin

• phenol

In the electron transport chain, in terminal oxidation, the cytochrome, which donates electrons to O₂ is

• cytochrome- b 

• cytochrome- c

• cytochrome- a₃

• cytochrome- a

Stomata open or close due to the ion

• Ca²⁺

• Na⁺

• K⁺

• Cu⁺

Flash of light in dark inhibits flnwering in

• SDP

• LDP

• LSDP

• DNP

The specific character of C₄  plants is

• bulliform cells

• Kranz anatomy

• parallel venation

• isobilateral leaf

Which of the following clogs the cavity of the xylem vessels?

• Tylosis

• Cystolith

• Hydathode

• Raphide

Which of the following has multiflagellate sperms?

• Equisetum

• Riccia

• Lycopodium

• Anthoceros