Molecular Genetics

Eukaryotic 80S ribosomes consist of a 60S large subunit and a 40S small subunit. The 60S subunit contains three rRNA molecules: 28S, 5.8S, and 5S, while the 40S subunit contains only one 18S rRNA. This is different from prokaryotic 70S ribosomes which have only 2 rRNA molecules total.

Reoviridae is the only virus family listed that contains double-stranded RNA as its genetic material. The name 'Reovirus' actually stands for Respiratory Enteric Orphan virus. Picornaviruses, Togaviruses, and Coronaviruses all contain single-stranded RNA genomes.

Interferons (IFNs) are a group of signaling proteins. 

Option (2) is the correct answer.

A sigma factor (σ factor) is a protein needed only for initiation of RNA synthesis. It is a bacterial transcription initiation factor that enables specific binding of RNA polymerase to gene promoters. 

In Genbank format, the sequence data begins with the ORIGIN keyword. This line marks the start of the actual nucleotide or amino acid sequence in the file. The other terms (sequence, start) are not the standard Genbank keywords.

In the CATH protein structure classification system, T stands for Topology. CATH is a hierarchical classification: Class, Architecture, Topology (arrangement of secondary structures), and Homologous superfamily. Topology describes the overall shape and connectivity of secondary structure elements.

SAPS (Statistical Analysis of Protein Sequences) is indeed used for primary structure analysis. It provides statistical information about amino acid composition, charge, and other primary structure features. The other options are not standard bioinformatics tools.

tRNA genes are specifically identified using tRNA scan, which is a bioinformatics tool designed to detect transfer RNA genes in genomic sequences. This tool uses specific algorithms and covariance models to recognize the characteristic cloverleaf secondary structure of tRNA molecules. The other options (translate tool, chime, hex) serve different purposes in bioinformatics.

Argonaute is a comprehensive database focused on mammalian microRNAs (miRNAs), providing detailed information about miRNA sequences, targets, and functions. While RDP deals with ribosomal RNA, tRNADB focuses on transfer RNAs, making Argonaute the correct choice specifically for miRNA data. miRNAs are small non-coding RNAs that regulate gene expression.

The generation of messenger RNA expression profiles is referred to as transcriptomics, which is the study of complete set of RNA transcripts (the transcriptome) produced by the genome under specific circumstances. While transcription is the process of making RNA, transcriptomics is the comprehensive analysis of expression patterns. Note: option B has a typo ('trasncriptomics' instead of 'transcriptomics') but is clearly the intended answer.

 The synthesis of DNA from an RNA template, via reverse transcription, produces complementary DNA (cDNA). Reverse transcriptases (RTs) use an RNA template and a short primer complementary to the 3' end of the RNA to direct the synthesis of the first strand cDNA, which can be used directly as a template for the Polymerase Chain Reaction (PCR).

 During transcription holoenzyme RNA polymerase binds to a DNA sequence and the DNA assumes a saddle like structure at that point. This sequence is called TATA box. It is a type of promoter sequence, which specifies to other molecules where transcription begins.

 Telomerase, also called telomere terminal transferase,is a ribonucleoprotein that adds the polynucleotide "TTAGGG" to the 3' end of telomeres, which are found at the ends of eukaryotic chromosomes.