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- Gene expression must be regulated inorderr to control protein synthesis.
- A repressor protein is a protein that is attached to the DNA strand, preventing RNA polymerase from binding to that site and transcribing specific genes.
- Molecules known as inducers can bind to tthe repressor protein and detach it from the DNA strand allowing RNA polymerase to transcribe specific genes.
- In prokaryotes, as the genetic message iss transcribed from DNA to mRNA, the translation begins simultaneously.
- In eukaryotic cells, genes consist of seqquences called exons and introns.
-Exons are the portions of the genes that aare translated into proteins, while introns are regions of DNA that do not code for protein synthesis.
- Only a very small percentage of the DNA iin a eukaryotic chromosome actually codes for proteins.
- Barbara McClintock discovered transposonss, which are genes that have the ability to "jump" from one Chromosome to another.
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