Gene expression/regulation questions!

[psychologie]

Hi there, was hoping someone would be able to help me out on the following questions, i have my SAC coming up soon 

-is 'mRNA leaves nucleus and moves into cytosol' actually part of the transcription process? and is 'mRNA binds to ribosome' part of translation? or do these things just happen in between transcription and translation?
-the proteome. is this all proteins being expressed in the ENTIRE organism at a certain time? or a certain CELL at a certain time?
-im getting confused about what a gene actually is now. there are structural genes WITHIN the lac operon; but i thought the lac operon was a gene itself? could you please explain what a gene actually is
-are transcription factors the same as activator/repressor proteins produced from regulatory gene?
-are homeotic genes the same as regulatory genes?

TIA 

[Ahmad_A_1999]

Hey TIA 

My definition of a gene is 'A region of DNA which may be translated into a polypeptide or a functional RNA molecule.'  As for an operon, it is found in prokaryotes only, it is a 'Functioning unit of DNA containing a cluster of genes under the control of a single promoter.' The Lac Operon contains 3 structural genes, hence I wouldn't say it is a gene itself. 

Transcription factors are proteins that regulate gene expression at the transcription stage, as they regulate the expression of other genes they are regulatory genes.

The proteome is the complete set of proteins expressed in a cell at any given time, my reasoning is because my textbook says the proteome differs between cell types, not sure though.

'mRNA leaving nucleus and moving into cytosol' isn't transcription, I think transcription ends when pre-mRNA and RNAP detach from the DNA.
'mRNA binds to ribosome' I would include that in translation as it is the initial stage, but I doubt you will get asked anything like this 

I'm sorry there are a lot of 'I thinks', best wait for someone else more capable of answering your questions because now I'm confused as well! 

[cookiedream]

Great answer by Ahmad!

I'd just like to add that recently it's been found that eukaryotes have operons as well (that's what my teacher told me at least).
And for the definition of a proteome, I'd say: "The complete set of proteins produced by a specific type of cell or organism at a given time in a given environment"

[Ahmad_A_1999]

Great answer by Ahmad!

I'd just like to add that recently it's been found that eukaryotes have operons as well (that's what my teacher told me at least).
And for the definition of a proteome, I'd say: "The complete set of proteins produced by a specific type of cell or organism at a given time in a given environment"

Oh great definition!

Also that blew my mind that there are operons in eukaryotes as well! going to have to go research that now!

[vcestressed]

Oh great definition!

Also that blew my mind that there are operons in eukaryotes as well! going to have to go research that now!

we just learn about lac operon because its the simplest operon to learn lol. In eukaryotes, the process is very complex which is why we dont learn it in 3/4 bio. thank god. . . there's already so much to learn about lac operon itself hehe

[Ahmad_A_1999]

we just learn about lac operon because its the simplest operon to learn lol. In eukaryotes, the process is very complex which is why we dont learn it in 3/4 bio. thank god. . . there's already so much to learn about lac operon itself hehe

Oh yeah I would definitely die if it got more complicated than the lac operon 

[psychologie]

Thanks for the help!!