A primary transcript is a linear copy of a transcriptional unit, the DNA segment between specific initiation and termination sequences. The primary transcript of both prokaryotic and eukaryotic tRNAs and rRNAs are post-transcriptionally modified by removing extra nucleotides. Transfer RNAs are then further modified to acquire special characters unique to tRNAs. In fact, many of […]
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The general transcription process can be applied to both prokaryotic and eukaryotic cells. The basic biochemistry for each is the same; however, the specific mechanisms and regulation of transcription differ between prokaryotes and eukaryotes. Transcription of eukaryotic genes is a far more complicated process than prokaryotes. The important points of differences are as follows: 1)
Transcription (part -2) Prokaryotic V/S Eukaryotic transcription Read More »
RNA Synthesis The synthesis of an RNA molecule from DNA is called Transcription. All eukaryotic cells have five major classes of RNA: ribosomal RNA (rRNA), messenger RNA (mRNA), transfer RNA (tRNA), and small nuclear RNA and microRNA (snRNA and miRNA). The first three are involved in protein synthesis, while the small RNAs are involved in mRNA
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1. The following are all characteristics of the genetic code except: Universal Degenerate Non-overlapping Ambiguous 2. Which of the following statements is not true concerning the role of Aminoacyl t-RNA synthetases: Charging an aminoacyl t-RNA synthetase (loading) with an amino acid is an energetically favorable reaction. For every amino acid, there are several Aminoacyl t-RNA
Translation- Multiple-choice questions Read More »
DNA in the living cell is subjected to many chemical alterations. If the genetic information encoded in the DNA is to remain uncorrupted, any chemical changes must be corrected. A failure to repair DNA produces a mutation. Agents that Damage DNA Radiations- Highly reactive oxygen radicals produced during normal cellular respiration as well as by other biochemical pathways Ionizing
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DNA Replication Basis for inheritance The fundamental process occurring in all cells for copying DNA to transfer the genetic information to daughter cells Each cell must replicate its DNA before division. Salient features of DNA replication 1) Semi-conservative Parental strands are not degraded Base pairing allows each strand to serve as a template for a
DNA Replication- A Quick Revision (lecture-2) Read More »
DNA Replication: the process of DNA Synthesis Purpose of replication Basis for inheritance The fundamental process occurring in all cells for copying DNA to transfer the genetic information to daughter cells Each cell must replicate its DNA before division. Salient features of DNA replication 1) Semi conservative Parental strands are not degraded Base pairing allows
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RNA (Ribonucleic acid ) Ribonucleic acid (RNA) is a polymer of purine and pyrimidine ribonucleotides linked together by 3′,5′-phosphodiester bridges analogous to those in DNA (Figure-1). Figure 1- Showing an RNA fragment, the ribonucleotides are linked together by 3′-5′ phosphodiester linkages. Ribose is the principal sugar in RNA Differences between RNA and DNA Although sharing
RNA Structure, types, and functions- a quick revision Read More »
DNA DNA – a polymer of deoxyribonucleotides found in chromosomes, mitochondria, and chloroplasts carries the genetic information. DNA structure a) Primary structure (figure-1) Represents the linear sequence of deoxyribonucleotides linked together by 3′-5′ phosphodiester linkages The informational content of DNA resides in the sequence in which monomers—purine and pyrimidine deoxyribonucleotides—are ordered. The polymer, as depicted,
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Q.1- Which statement best describes the ‘semi-conservative replication’ of DNA? A) In each replication cycle, only one of the two DNA strands is replicated B) In each replication cycle, one of the parental strands is conserved C) In each replication cycle, the daughter cells acquire either the parental stands or new stands D) Only half
Molecular Biology-Multiple-choice questions (set-2) Read More »
