Module 07: Nuclear Structure and Function Flashcards
What is transcription?
Synthesis of RNA from a DNA template
What surrounds the nucleus?
A double membrane (two lipid bilayers)
Where is most of the mRNA transcribed in eukaryotes?
The nucleus
Where is mRNA translation initiated?
In the cytosol
Where would you find the proteins that replicate DNA during the S-phase of the cell cycle?
In the nucleus
Where are the proteins that replicate DNA synthesized?
In the cytosol
Where is most rRNA of a eukaryote transcribed?
In the nucleus
Where is rRNA functional?
In the cytosol
What does the word “zipcode” refer to?
It is a sequence of amino acids that specifies where proteins are delivered in a cell
What do the dark shapes on a transmission electron micrograph represent?
Area of polar molecules
What are lipid anchors?
They covalently attach to proteins and localize that protein to a membrane
Why do lipid anchors associate with membranes?
The hydrocarbon chain of the lipid is non-polar and therefore associates with the non-polar interior of the membrane
What is immunofluoresence microscopy?
It uses specific antibodies to recognize specific macromolecules so their sub-cellular distribution can be visualized
What is freeze-fracture microscopy?
It uses a sharp knife to fracture a frozen sample through the middle of a lipid bilayer
What do the holes and bumps in a freeze-fracture image represent?
Position of proteins
