Which statement is correct about RNA biosynthesis?

Personally, I think the correct answer is: transcription does not require RNA primers, DNA replication.

before you need it. B: Eukaryotic cell genes are divided into introns and exons, and the transcribed hnRNA needs to be modified by removing introns to form a translatable mRNA template. C: Transcription in the nucleus.

Completed within. E: E. coli RNA polymerase consists of 2 subunits, 1 subunit, 1 subunit'A subunit and a subunit make up the core enzyme, and when a subunit is added, it becomes a polymerase holoenzyme.

The subunit, also known as the factor, has the main function of improving the affinity of RNA polymerase for the DNA sequence in the promoter region. At the beginning of transcription, the factor is present when the nascent RNA strand reaches 6-9 nucleotides.

A stable enzyme-DNA-RNA ternary complex can be formed, the release factor and transcription enter the elongation phase. So RNA polymerase is not involved in the whole transcription process in the form of a holoenzyme.

The first way is to synthesize RNA under the guidance of DNA, the second way is to reverse transcribe RNA into DNA, and then synthesize RNA, that is, reverse transcription RNA viral gene replication, and the third way is to directly synthesize RNA from RNA, which also exists in some RNA viruses.

The answer is D, and the reason is basically the same.

With regard to the biosynthesis of RNA containing tama, the following statement is incorrect () transcription initiation is controlled by DNA promoters, and transcription termination is controlled by termination self.

b.With the exception of you and t, the base sequence of the sense strand of the DNA template is the same as that of the synthesized RNA.

Polymerases are made up of five subunits, of which the subunits recognize the role of the initiation signal in the DNA molecule.

For synthesis, the DNA double-strands must be unwound by DNA chain enzymes.

Polymerases do not need primers to synthesize RNA.

Correct answer: d

With regard to DNA-directed RNA synthesis, which of the following is false()aRNA polymerase can catalyze the biogenesis of phosphodiester bonds only in the presence of DNA.

b.During transcription, RNA polymerase requires primers.

The synthesis of the chain is from 5 to 3 ends.

d.Most of the time, there is only one strand of DNA as a template.

Correct Sun Kuan Answer: B

Which of the following statements about DNA-directed RNA synthesis is incorrect? （）a.RNA polymerase can catalyze the formation of phosphodiester bonds only in the presence of DNA.

b.RNA polymerase requires primers during transfection.

The dry and noisy synthetic direction of the chain is from the 5' to 3' ends.

d.Most of the time, there is only one strand of DNA that acts as a template for RNA.

Correct answer: B

RNA synthesis is very similar to DNA synthesis with three differences:

1) RNA strand synthesis does not require primers and can be directly initiated, while DNA synthesis must be guided by primers.

2) The raw material for RNA synthesis is nucleoside triphosphate, and DN is deoxynucleoside triphosphate.

3) Only one strand of DNA is used as a template for RNA synthesis, and both strands are used as templates separately for DNA synthesis.

RNA synthesis: RNA polymerase enters the enzyme cleavage site in the non-coding region of DNA, unwinds the DNA to become a single strand, and the ribonucleotide forms an RNA strand (messenger RNA) by the law of base complementary pairing. RNA processing takes place mainly within the nucleus, with a few reactions taking place in the cytoplasm.

mRNA is processed in the nucleus and transported out to the cytoplasm, and the processing of trRNA is in the cytoplasm, and the RNA is also processed in the cytoplasm, and the RNA and tRNA are transcribed in the same primary transcription product (i.e., the precursor).

Ribonucleic acid (RNA) is a carrier of genetic information found in biological cells and some viruses and viroids. RNA is made up of ribonucleotides condensed by phosphodiester bonds to grow into chains. A ribonucleotide molecule is made up of phosphoric acid, ribose sugar, and bases.

RNA is a single strand formed by transcribing a strand of DNA as a template based on the principle of base complementary pairing, and its main function is to realize the expression of genetic information on proteins, and is a bridge in the process of genetic information transmission.

DNA synthesis: first, the double helix is unwound by helicase and topoisomerase, and then a DNA polymerase is responsible for the synthesis of the advance strand; The other binds to the delayed strands to create discontinuous Okazaki fragments, which are then bonded by DNA ligase. The DNA of prokaryotes is mainly synthesized in the nucleoid, and a small part is also synthesized in the cytoplasm (such as the plasmid of bacteria), and the DNA of eukaryotes is mainly synthesized in the nucleus, and a small amount is synthesized in the mitochondria.

Plant cell organelles: DNA synthesis can also be carried out in chloroplasts.

Deoxyribonucleic acid (DNA), also known as deoxyribonucleic acid, is a molecule, double-stranded structure, composed of deoxyribonucleotides (composition: deoxyribose sugar and four nitrogenous bases). It can form genetic instructions to guide biological development and life functions.

The main function is the long-term storage of information, which contains instructions for the construction of other compounds in the cell, such as proteins and RNA.