A codon is a sequence of three DNA or RNA nucleotides that corresponds with a specific amino acid or stop signal during protein synthesis. Does tRNA carry codons? The tRNA carries the amino acid that corresponds to that codon. The next mRNA codon is now exposed in the ribosome’s otherRead More →

A transfer RNA (abbreviated tRNA and formerly referred to as sRNA, for soluble RNA) is an adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length (in eukaryotes), that serves as the physical link between the mRNA and the amino acid sequence of proteins. Which RNA soluble inRead More →

Codon (biology definition): the‌ ‌amino‌ ‌acid‌ ‌coding‌ ‌unit‌ ‌in‌ ‌DNA‌ ‌or‌ ‌messenger‌ ‌RNA (mRNA). ‌ ‌The‌ ‌string‌ ‌of‌ ‌codons‌ ‌in‌ the ‌mRNA‌ ‌specifies‌ ‌the‌ ‌order‌ ‌of‌ ‌amino‌ ‌acids‌ ‌in‌ ‌the‌ ‌encoded‌ ‌protein. Apart from amino acids, there are also codons that specify start/stop signals. Are codons on mRNA? The three-letterRead More →

Ribonucleases (RNases) are a large group of hydrolytic enzymes that degrade ribonucleic acid (RNA) molecules. These are nucleases that catalyze the breakdown of RNA into smaller components. They are a superfamily of enzymes which catalyze the degradation of RNA, operating at the levels of transcription and translation. How is DNARead More →

PCR amplifies a specific region of a DNA strand (the DNA target). Most PCR methods amplify DNA fragments of between 0.1 and 10 kilo base pairs (kbp) in length, although some techniques allow for amplification of fragments up to 40 kbp. What is RNA amplification? Linear RNA amplification is anRead More →

Similarities between DNA and RNA: Both are made up of five carbon- pentose sugar, phosphate and nitrogenous bases. Both are polynucleotide chains made up of a single nucleotide unit or monomers. Both biomolecules are synthesised by the polymerase enzyme. Practically, both DNA and RNA can be precipitated using alcohol. WhereRead More →

In the minimal in vitro transcription assay containing only these general transcription factors and purified RNA polymerase II, TBP remains bound to the TATA-box as the polymerase transcribes away from the promoter region, but the other general transcription factors dissociate. Does RNA polymerase bind to the operator? Between the promoterRead More →

Protozoa are eukaryotic unicellular organisms, which together with single-cell algae and slime molds belong to the Protista kingdom. They possess a simpler and more primitive structure than the members of the animal kingdom. The protozoans contain a membrane-surrounded nucleus and cellular organs. What does protozoa not have? Walls, Pellicles, scales,Read More →

The four bases that make up this code are adenine (A), thymine (T), guanine (G) and cytosine (C). Bases pair off together in a double helix structure, these pairs being A and T, and C and G. RNA doesn’t contain thymine bases, replacing them with uracil bases (U), which pairRead More →