Regulation of Gene Expression Flashcards
What is a repressible operon?
One that is usually on until the co-repressor activates the repressor and stops transcription
What is an inducible operon?
One that is usually off until the induced inactivates the repressor and turns on transcription
What is a repressible operon called?
The trp operon
What is a inducible operon called?
The lac operon
Where is the eukaryotic gene expression regulated?
- Transcription
- RNA processing
- Protein translation
Chromatin structure and gene expression can be influenced by what?
Chemical modifications of the histone proteins of the nucleosome
What condenses chromatin and reduces transcription?
The addition of methyl groups
What are control elements?
Segments of noncoding DNA that serve as binding sites for transcription factors that can help regulate transcription
What is microRNA (miRNA)?
Single, small stranded RNA molecules that can bind complementary sequences in mRNA
How are cells organized?
Into tissues, organs, organ systems, and the whole organism
The transformation from zygote to adult results from what?
Cell differentiation and morphogenesis
What is cell differentiation?
The process by which cells become specialized in structure and function
What is morphogenesis?
The physical processes that give an organism its shape
What are cytoplasmic dterminants?
Maternal substances in the egg that influence early development
What is induction?
When signal molecules from embryonic cells cause changes in nearby target cells
What is determination?
Irreversibly commits a cell to becoming a particular cell type
What is differentiation?
The process by which a cell attaints its determined fate
What is pattern formation?
The development of a spatial organization of tissues and organs
What is positional information?
The molecular cues that control pattern formation
What are homeotic genes?
Discovered by Lewis, homeotic genes control pattern formation in the late embryo, larva, and adult stages
