Evolution Quote by Robert M. Sapolsky
““What is that 95 percent? Some is junk—remnants of pseudogenes inactivated by evolution.fn4,3 But buried in that are the keys to the kingdom, the instruction manual for when to transcribe particular genes, the on/off switches for gene transcription. A gene doesn’t “decide” when to be photocopied into RNA, to generate its protein. Instead, before the start of the stretch of DNA coding for that gene is a short stretch called a promoterfn5—the “on” switch. What turns the promoter switch on? Something called a transcription factor (TF) binds to the promoter. This causes the recruitment of enzymes that transcribe the gene into RNA. Meanwhile, other transcription factors deactivate genes.””
About This Quote
Source Book: Behave: The Biology of Humans at Our Best and Worst, 2017
Gene expression is regulated by promoters and transcription factors, not by conscious decision.
In simple terms: Genes are turned on/off by molecular switches.
Key Takeaway
Understand molecular regulation.
Themes
biology
genetics
regulation
Mood
curious
analytical
Type
scientific
educational
When to use this quote
- research labs
- medical genetics
- education
- biotech development
Key Concepts
promoter
transcription factor
gene expression
Questions to Reflect On
- How do external signals affect transcription?
- What role do epigenetics play?
A Different Perspective
Complex regulation can be influenced by environmental factors, not just DNA.
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