T2M1: Transcription

Question 1

Central dogma

Answer 1

Process of copying and interpreting genes into proteins

Question 2

RNA polymerase

Answer 2

Attaches itself to specific promoters regions so RNA can be transcribed from DNA
moves along DNA in 3’ to 5’ direction
Will transcribe until reach terminator sequence

Question 3

Prokaryotic DNA

Answer 3

Within mon-membrane bound nucleoid 
Nucleotide sequence (TATAAT and TTGCCA) enhance raté of transcription
Use single type of RNA polymerase with sigma factors

Question 4

Sigma factor

Answer 4

Facilitate binding to promote region of DNA

Question 5

Rho independent terminator sequence

Answer 5

Consist of inverted nucleotide repeat sequence
Transcribed and then fold back on themselves to form G-C rich hairpin loop which causes RNA polymerase to pause and release

Question 6

Rho-dependant terminator sequence

Answer 6

Use specific prokaryotic protein (Rhofactor) which binds to ans uses ATP to move along RNA transcript while unwinding it from DNA template
Able to destabilize interaction between RNA and DNA =release

Question 7

RNA polymerase I

Answer 7

Transcribed genes for ribosomal RNA

Question 8

RNA polymerase III

Answer 8

Transcribes genes for transfer RNA and small regulatory RNA molecules

Question 9

RNA polymerase II

Answer 9

Transcribes mRNA -which serves as templates for production of protein molecules

Question 10

Post transcriptional modifications purpose

Answer 10

Allow export of mRNA from nucleus, help protect against ribonuclease enzymes that target phosphodiester bonds, help w attachment of ribosomes and initiation of translation once mRNA reaches cytoplasms

Question 11

5’ end cap

Answer 11

Involves modified G’s referred to as 7-methylguanosine

To attach this, 5’ phosphate removed by enzymes and guanosyl transferase enzymes catalyze attachment

Question 12

Poly (A) tail

Answer 12

Multiple A’s added to 3’ end

Process called polyadenylation

Question 13

Exon

Answer 13

Sequence of mRNA necessary for coding sequence of amino acids in proteins

Question 14

Introns

Answer 14

Intervening sequences

Question 15

Splicosomes

Answer 15

Large molecules machine which catalysés process of RNA splicing
Composed of 5 small ribonucleoproteins (snRNP) made of small nuclear RNA and proteins and able to recognize splice sites within intron