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Which of the following is a part of a dna molecule. select all answers that are correct. select one or more:

a. poly a tail
b. silencer
c. promoter
d. sigma
e. transcription factor
f. enhancer

User Ranjith KP
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Final answer:

The parts of a DNA molecule amongst the options are the promoter, silencer, and enhancer. The poly A tail is associated with mRNA; the sigma subunit and transcription factors are proteins that interact with DNA but are not part of its structure.

Step-by-step explanation:

Within a DNA molecule, several elements play crucial roles in the process of transcription and gene expression. From the options provided, the following are parts of a DNA molecule:

  • Promoter (a): This is a specific sequence of DNA nucleotides where RNA polymerase binds to initiate transcription.
  • Silencer (b): DNA sequences that can bind transcription regulatory proteins (repressors) to inhibit the expression of a gene.
  • Enhancer (f): DNA sequences that can increase the rate of transcription when regulatory proteins (activators) bind to them.

On the other hand, elements like the poly A tail, sigma subunit, and transcription factors are not parts of the DNA molecule:

  • The poly A tail is added post-transcriptionally to the 3' end of mRNA.
  • The sigma subunit is a component of the prokaryotic RNA polymerase that confers specificity to transcription.
  • Transcription factors are proteins that regulate the transcription of genes by binding to DNA but are not part of the DNA molecule itself.
User Sharon Soussan
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