https://padlet.com/lissien2017/1v2nxmcit42bwbtf By: Lissien Yanez, Daniel García and Diego Medina en-us 2021-10-16 15:09:10 UTC 2025-11-20 11:57:47 UTC hello@padlet.com https://padlet.net/icons/png/1f4da.png lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821213419 Is the process by which the nucleotide sequence of a gene directs protein synthesis. In this way, cells use protein synthesis to respond to particular needs and react to changes in their environment.]]> 2021-10-16 15:29:32 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821213419 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821233181 IN  PROKARYOTIC CELL TRANSCRIPTION AND TRANSLATION BOTH OCCUR IN THE CYTOPLASM AT ABOUT THE SAME . IN EUKARYOTIC CELLS WHERE  DNA IS LOCATED THE NUCLEUS, THESE PROCESS ARE SEPARATED BOTH IN LOCATION TIME.]]> 2021-10-16 15:55:02 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821233181 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821241552 The regulation of gene expression in prokaryotic cells occurs at the transcriptional level. There are two majors kinds of proteins that control prokaryotic transcription: repressors and activators. In the trp operon, the trp repressor is itself activated by binding to tryptophan.]]> 2021-10-16 16:06:04 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821241552 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821259609 ^{An operon is a region of DNA that includes a promoter, an operator, and one or more structural genes that code for all the proteins needed to do a specific task. The promoter is a segment of DNA that helps the enzyme RNA polymerase locate the starting point for transcription . The DNA segment that actually turns genes on or off is the operator.}]]> 2021-10-16 16:29:34 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821259609 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821288604 The lac operon acts like a switch. When lactose is present, the lac operon is switched on to allow transcription. The lactose binds to the repressor, which makes the repressor change shape and fall off the lac operon. RNA polymerase is able to transcribe the DNA into RNA. This RNA is translated to form enzymes that work together to break down the lactose.

When lactose is absent, the lac operon is switched off to prevent transcription of the lac genes, thus saving the cell's resources. When lactose is absent, the protein binds to the operator, which blocks RNA polymerase from transcribing the genes. Because the protein blocks or represses-transcription, it is called a repressor protein.]]> 2021-10-16 17:09:10 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821288604 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821295494 2021-10-16 17:18:21 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821295494 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821301290 Prokaryotic transcription and translation occur simultaneously in the cytoplasm, and regulation occurs at the transcriptional level. Eukaryotic gene expression is regulated during transcription and RNA processing, which take place in the nucleus, and during protein translation, which takes place in the cytoplasm.

]]> 2021-10-16 17:27:16 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821301290 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821405572
 Control of gene expression in eukaryotic cells occurs at epigenetic, transcriptional, post-transcriptional, translational, and post-translational levels. Post-translational control refers to the: regulation of gene expression after transcription.]]> 2021-10-16 20:23:54 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821405572 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821622747 The epigenome determines how easily the enzymes of transcription can access regions of the chromosome to turn genes on or off. When histones or DNA are changed chemically , the result may change the accessibility of the DNA for transcription .]]> 2021-10-17 03:52:08 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821622747 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821623790 In eukaryotes, transcription factors bind to promoters and other DNA sequences to help RNA polymerase recognize the start of a gene.]]> 2021-10-17 03:53:51 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821623790 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821625619 The cell makes many changes to mRNA after transcription. A specialized nucleotide is added to the beginning of each mRNA molecule, forming a cap. The end of the mRNA molecule gets a string of nucleotides called the tail that improves stability and helps the mRNA molecule exit the nucleus. The "extra footage in the mRNA molecule takes the form of nucleotide segments , called introns, that are not included in the final protein. The nucleotide segments that code for parts of the protein are called exons . Introns occur between exons .]]> 2021-10-17 03:57:04 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821625619 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821635774 Translation takes place after mRNA is moved into the cytoplasm, and it is the process that makes a protein from amino acids. In eukaryotes, gene expression may also be regulated by changes to the translation process.]]> 2021-10-17 04:12:32 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821635774 lissien2017 https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821652070 2021-10-17 04:36:48 UTC https://padlet.com/lissien2017/1v2nxmcit42bwbtf/wish/1821652070