ICAR AIEEA PG Plant Science 14 July 2023 Shift-1 Paper

Two distinct steps of biological nitrification:

• Step 1 (Ammonia oxidation): Oxidation of ammonia to nitrite ($2\text{NH}_4^+ + 3\text{O}_2 \rightarrow 2\text{NO}_2^- + 4\text{H}^+ + 2\text{H}_2\text{O}$) by ammonia-oxidizing bacteria (AOB): Nitrosomonas, Nitrosococcus, Nitrosospira.
• Step 2 (Nitrite oxidation): Oxidation of nitrite to nitrate ($2\text{NO}_2^- + \text{O}_2 \rightarrow 2\text{NO}_3^-$) by nitrite-oxidizing bacteria (NOB): Nitrobacter, Nitrococcus, Nitrospira.

Locations of major ICAR research institutes:

• National Dairy Research Institute (NDRI): Karnal, Haryana: (A)-(V).
• Central Arid Zone Research Institute (CAZRI): Jodhpur, Rajasthan: (B)-(III).
• Central Institute for Cotton Research (CICR): Nagpur, Maharashtra: (C)-(I).
• National Bureau of Agricultural Insect Resources (NBAIR): Bengaluru, Karnataka: (D)-(II).
• Indian Institute of Millets Research (IIMR): Hyderabad, Telangana: (E)-(IV).

Millet conservation recognition:

• Lahari Bai, a 27-year-old Baiga tribal woman from Dindori district of Madhya Pradesh, established an indigenous seed bank conserving over 150 rare varieties of millets and wild crops in her home.
• During the International Year of Millets (IYM 2023), she gained national acclaim and was celebrated as the 'Millet Queen of India' (Shree Anna Brand Ambassador).

Translation initiation in eukaryotes:

• The universal initiation start codon is AUG on mRNA.
• In eukaryotes, the initiator tRNA ($tRNA_i^{Met}$) carries unformylated Methionine (Met), establishing methionine as the first amino acid at the N-terminus of all nascent eukaryotic polypeptides.
• In prokaryotes, the initiating residue is N-formylmethionine (fMet).