Term
| why do we say nuclear envelope instead of nuclear membrane? |
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Definition
| the nuclear envelope is a double membrane |
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Term
| what organelle is physically connected to the nuclear envelope? |
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Definition
| rough endoplasmic reticulum |
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Term
| t/f - the nucleas regulates entry and exit of molecules |
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Definition
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Term
| what is the name of the passageways that molecules use to enter or exit the nucleus? |
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Definition
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Term
| where is the androgen receptor located |
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Definition
| in the cytoplasm by free ribosomes |
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Term
| what size molecules can diffuse across the nuclear pores? |
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Definition
| less than or equal to 20,000 daltons |
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Term
| what if the GTP was non-hydrolyzable |
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Definition
1) there would be a build up of Ran-GTP bound to importins in the nucleoplasm
2) there wouldn't be any ran-GTP to switch out the ran-GDP in the nucleus so no exportation will happen |
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Term
| what is the difference between DNA and chromatin fibers? |
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Definition
| chromatin fibers have the DNA wrapped around histones and other proteins |
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Term
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Definition
| chromatin that are more loosely dispersed and are transcriptionally active |
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Term
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Definition
| chromatin is more tightly packed and i transcriptionally inactive |
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Term
| what is the function of the nucleolus? (2) |
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Definition
1) site of rRNA synthesis
2) site of initial assembly of ribosomes |
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Term
| describe the nuclear import process |
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Definition
1) cargo is tagged with NLS
2) importin binds to the cargo and NLS
3) enters into the nucleus
4) ran-GTP binds to the import in
5) cargo lets go
6)ran-gtp and importin leave the nucleus
7) ran-GTP is hydrolyzed to gdp and pi
8) releases the importin to now go bind to other cargo |
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Term
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Definition
| actively transport selective molecules of any size in either direction |
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Term
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Definition
RNA binds to NES
RNA, NES, exportin, cargo binds to RAN-GTP and leaves through nuclear pore
GTP hydrolysis to let go of everything |
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Term
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Definition
| about 200 base pairs of DNA wrapped around a histone protein, bead on a string |
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