Erstellt von Yinka F
vor fast 7 Jahre
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All the cells in an organism carry the same genes (DNA), but the structure and function of different cells varies. Why?
Name the 3 levels in which gene expression is controlled
Complete the sentences:
Gene expression can be controlled at the transcriptional level by altering the ______ of transcription of ______. For example, increased transcription produces more ______, which can be used to make more protein.
What are transcription factors?
What is the name for transcription factors that start transcription?
What is the name for transcription factors that stop transcription?
TRUE OR FALSE:
The shape of the transcription factor has no effect on its ability to bind to DNA
Where do transcription factors bind to in eukaryotes?
Where do transcription factors bind to in prokaryotes?
What is an operon?
What does the structural gene on an operon code for?
What are the control elements on an operon composed of?
What does the regulatory gene on an operon code for?
Complete the sentences:
E. coli is a ___________ that respires glucose, but it can use _________ if glucose isn't available. The lac operon has three structural genes - ______, ______ and ______. The lac operon is around ________ base pairs long.
Describe the structure of the lac operon
Outline what happens at the lac operon when lactose is NOT present
Outline what happens at the lac operon when lactose IS present
What is post-transcriptional level control?
Complete the sentences:
After transcription, mRNA in eukaryotic cells is ________ - that's because genes in eukaryotic DNA contains sections that don't code for _________ ______. These sections are called _________. The rest of the DNA that do code for amino acids are called ________.
What happens to the introns and exons during transcription (before the mRNA strand exits the nucleus)?
What are mRNA strands containing introns and exons called?
What does post-translational level control involve?
Describe how some molecules control protein activation using cAMP
PKA is an enzyme made of four subunits. What happens when cAMP binds? What happens when cAMP does NOT bind?