Answer:
b. several transcription factors have bound to the promoter.
Explanation:
The initiation of RNA synthesis in eukaryotes includes assembly of RNA polymerase and several transcription factors at the promoter. The binding of TATA-binding proteins (TBP) to the TATA box serves to stabilize the TFIIB-TBP complex at the promoter.
The TFIIB is a transcription factor that is bound to both transcription factor binding proteins and DNA. This is followed by the binding of transcription factor TFIIF and the RNA Pol II enzyme to the TFIIB-TBP complex. Then the other transcription factors such as TFIIE, TFIIB and TFIIH also join the complex. The result is the formation of a closed complex.
Here, the function of TFIIA is to stabilize the TFIIB and TBP at promoter while TFIIB serves in the recruitment of RNA Pol II enzyme to the promoter.
TFIIE facilitates binding of TFIIH and has helicase activity to unwind the DNA duplex while TFIIF serves to prevent the binding of Pol II enzyme to the DNA sequences other than promoters.
Finally, the transcription factor TFIIH phosphorylates the enzyme RNA polymerase II and brings about a conformational change in the whole complex to facilitate the start of transcription.
<span>Chlamydomonas is a eukaryote. A Eukaryote is an organism that consists of a cell or cells in which the genetic material DNA, is in the form of chromosomes and is enclosed within a well-defined nucleus, which is surrounded by nuclear membrane. </span>
The correct answer is B) mitochondria
You can use this website to improve your knowledge about the mitochondria and its functions https://www.thoughtco.com/mitochondria-defined-373367
Answer: Despite the availability of antibiotics that lyse E coli cells, the reason this is NOT recommended in course of treatment is because the antimicrobial agents may trigger the lytic cycle and result in increased toxin expression.
Explanation:
Shiga toxin (Stx) are toxins which are produced by shiga toxin-producing Escherichia coli ( STEC). The antimicrobial agents may also trigger the lytic cycle and result in increased toxin expression.
