Answer:
The ability of sequences within the leader mRNA to pair with one another and form stem-lopp structures
Explanation:
A form of feedback regulation controls the trp operon by regulating transcription termination, a mechanism referred to as Attenuation.
-In the presence of high concentrations of tryptophan, RNA polymerase ceases transcription shortly after initiation in a region called the leader sequence.
-If the concentration of tryptophan is low, transcription does not terminate until the entire operon is transcribed. The mechanism of attenuation links alternative RNA secondary structures to transcription termination.
-Immediately after transcription, RNA from the leader region folds into one of two alternative secondary structures.
-One of these structures is a transcription termination signal that stops RNA polymerase from continuing to the end of the operon.
-The alternative structure does not contain a transcription termination signal and allows transcription of a single mRNA that encodes all the structural genes.
-The decision as to which of the two alternative RNA structures formed is regulated by the concentration of tryptophan.
Answer:
A tetrad is a four part structure formed during the prophase I of meiosis I which is formed by the homologous chromosomes which is composed of two identical chromatids.
The tetrad formation takes place when a proteinaceous meiosis-specific nuclear structures called synaptonemal complex is formed between two homologous chromosomes which mediates the tight associations of the homologous chromosomes.
The synaptonemal complex consists of two ladder like lateral elements which attaches the chromatin of the homologius chromosomes. The central region of the synaptonemal complex is composed of the transverse filaments and the central element which bridge the space between the the lateral elements.
This attachment of the chromatin to the synaptonemal complex mediates the chromosome pairing and form tetrad.
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It said I couldn't upload with swearwords??
Precipitation is the correct answer
