Basic Microbiological Techniques

• Plant Trace Element Concentrations:
• Manganese (Mn): Typical physiological requirement in plant tissue ranges around 0.1 to 0.5 ppm in solution culture $\rightarrow$ (I)
• Molybdenum (Mo): The lowest required micronutrient, functioning in nitrogen metabolism around 0.01 to 0.05 ppm $\rightarrow$ (III)
• Iron (Fe): Required in the highest relative concentration among micronutrients for chlorophyll synthesis and redox chains, typically 0.5 to 5.0 ppm $\rightarrow$ (IV)
• Zinc (Zn): Essential for auxin synthesis and enzyme activation, maintained around 0.02 to 0.2 ppm $\rightarrow$ (II)
• Systematic Match: (A)-(I), (B)-(III), (C)-(IV), (D)-(II) (Option 3).

Correct option: (3) (A) - (II), (B) - (Ill), (C) - (IV), (B) - (1)

• Ribozyme / RNase P $

ightarrow$ (IV) Cleavage of RNA genome: Catalytic RNA molecules that specifically bind target viral RNA through complementary base pairing and cleave phosphodiester bonds.

• Coat Protein $

ightarrow$ (III) Interferes with uncoating: Transgenic expression of viral coat protein (CP-mediated resistance) prevents the disassembly and uncoating of invading virions upon initial cell entry.

• cDNA of RNA satellite $

ightarrow$ (I) Interferes with replication: Satellite RNAs attenuate symptom severity by competing with helper virus genomic RNA for viral replicase machinery.

• Antisense RNA $

ightarrow$ (II) Binds to RNA preventing function: Hybridizes with complementary sense viral mRNA or genomic RNA, blocking translation and triggering enzymatic degradation.

Correct option: (4) (A) - (IV), (B) - (MN), (C)~ (), (B) - (HN)

• Rice Chromosome Number: Cultivated rice (Oryza sativa) is a diploid species with $2n = 2x = 24$ chromosomes.
• Meiotic S-phase & Chromatid Count: Prior to entering Prophase I of Meiosis I, the cell completes interphase DNA replication. Consequently, each of the 24 chromosomes consists of two identical sister chromatids joined at the centromere.
• Calculation:

Correct option: (3) 48