Gibberellin was first extracted from

• Gibberella fujikuro

• algae

• bacteria

• roots of higher plants

How many sperms are formed by four primary spermatocytes

• 1

• 4

• 16

• 32

The enzyme responsible for atmospheric nitrogen fixation is

• nitrogenase

• hydrogenase

• oxygenase

• carboxylase

Which of the following is non symbiotic bio-fertilizer

• YAM

• Anabaena

• Azotobacter

• Rhizobium

Lactic acid is produced by Rhizopus species 

• R. oryzae 

• R. stolonifer

• R. nodosus 

• R. sexualis

Insects captured by insectivorous plants fulfil their requirements of

• enzymes

• oxygen

• nitrogen

• water

Non-protein part of enzyme is known as

• holoenzyme

• apoenzyme

• prothetic group

• none of these

The alga used for quick sewage disposal is 

• Ulothrix

• Cladophora

• Volvox

• Chiarella

Convergent Evolution' is shown by

• homologous organs

• analogous organs

• vestigial organs

• all of the above

0n high mountains, difficulty in breathing is due to

• decrease in partial pressure of O₂

• decrease in amount of O₂

•  increase in CO₂ concentration

• all of the above