Bio 200 exam 2 EXPECTED QUESTIONS WITH VERIFIED
ANSWERS
Question 1.
gene expression
ANSWER
process of converting stored information into molecules that actually do things in the cell
Question 2.
central dogma of micro-biology
ANSWER
DNA->RNA->protien->work
Question 3.
supercoiling
ANSWER
DNA coils back on itself, coils with-
in coils, condenses DNA to fit it into cells.
wraps around proteins called histones
must still be open enough to "read"
Question 4.
How do you get from a genotype to a phenotype?
ANSWER
DNA sequence codes for mRNA which goes to tRNA which makes amino acids which form
proteins.
,Question 5.
transcription
ANSWER
DNA to RNA. All types of RNA made from transcription, but not all types of RNA make proteins.
polymerization of RNA monomers by RNA polymerase. RNA has base sequence
complementary to the DNA
1) NTP monomers base pair witht he DNA template
2)RNA polymerase catalyzes a reaction that cleaves off two phosphates and forms a
phosphodiester linkage between the 3' end of the growing mRNA and the new ribonucleoside
monophosphate
3) an RNA that is complementary to the gene is synthesized in the 5' to 3' direction
Question 6.
translation
ANSWER
ribosomes attach to mRNAs and begin synthesizing proteins.
Question 7.
initation (translation)
ANSWER
1) small section of rRNA in small subunit of the ribosome binds to the RBS on the mRNA.
2) first tRNA binds to the ribosome and the start codon (near the 5' end but not actually at the
5' end)
3) large subunit joins the complex
Question 8.
elongation (translation)
ANSWER
1) E and A sites of ribosome are empty
2) tRNA binds to the A site by complmentary base pairing between the codon and anticodon
3) A and P sites occupied, peptide bond formation begins
4) translocation: eleongation factor moves the ribosome from 5' to 3', using GTP for energy,
moves uncharged tRNA to the E site, moves tRNA holding the growing chain to the P site,
opens up the A site
**highly dynamic, ribosome is constantly changing shape
, Question 9.
termination (translation)
ANSWER
release factor recognizes stop codon and fills the A site. Stops are found near the 3' end but
not at the very end. release factor fits tightly into the A site because it is similar in size and
shape to tRNA but it is asctually a protein.
polypeptide and uncharged tRNAs are released from the ribosome. ribosome separates from
the mRNA and its 2 subunits separate from each other.
Question 10.
ribozyme
ANSWER
ribosomes are not enzymes because their active sites are entirely RNA, not protein. They
would still function if all of the protein was removed from them. evolutionarily speaking RNA
came before DNA and protein.
Question 11.
polyribosomes
ANSWER
begin translation before transcription is complete. coupling
ANSWERS
Question 1.
gene expression
ANSWER
process of converting stored information into molecules that actually do things in the cell
Question 2.
central dogma of micro-biology
ANSWER
DNA->RNA->protien->work
Question 3.
supercoiling
ANSWER
DNA coils back on itself, coils with-
in coils, condenses DNA to fit it into cells.
wraps around proteins called histones
must still be open enough to "read"
Question 4.
How do you get from a genotype to a phenotype?
ANSWER
DNA sequence codes for mRNA which goes to tRNA which makes amino acids which form
proteins.
,Question 5.
transcription
ANSWER
DNA to RNA. All types of RNA made from transcription, but not all types of RNA make proteins.
polymerization of RNA monomers by RNA polymerase. RNA has base sequence
complementary to the DNA
1) NTP monomers base pair witht he DNA template
2)RNA polymerase catalyzes a reaction that cleaves off two phosphates and forms a
phosphodiester linkage between the 3' end of the growing mRNA and the new ribonucleoside
monophosphate
3) an RNA that is complementary to the gene is synthesized in the 5' to 3' direction
Question 6.
translation
ANSWER
ribosomes attach to mRNAs and begin synthesizing proteins.
Question 7.
initation (translation)
ANSWER
1) small section of rRNA in small subunit of the ribosome binds to the RBS on the mRNA.
2) first tRNA binds to the ribosome and the start codon (near the 5' end but not actually at the
5' end)
3) large subunit joins the complex
Question 8.
elongation (translation)
ANSWER
1) E and A sites of ribosome are empty
2) tRNA binds to the A site by complmentary base pairing between the codon and anticodon
3) A and P sites occupied, peptide bond formation begins
4) translocation: eleongation factor moves the ribosome from 5' to 3', using GTP for energy,
moves uncharged tRNA to the E site, moves tRNA holding the growing chain to the P site,
opens up the A site
**highly dynamic, ribosome is constantly changing shape
, Question 9.
termination (translation)
ANSWER
release factor recognizes stop codon and fills the A site. Stops are found near the 3' end but
not at the very end. release factor fits tightly into the A site because it is similar in size and
shape to tRNA but it is asctually a protein.
polypeptide and uncharged tRNAs are released from the ribosome. ribosome separates from
the mRNA and its 2 subunits separate from each other.
Question 10.
ribozyme
ANSWER
ribosomes are not enzymes because their active sites are entirely RNA, not protein. They
would still function if all of the protein was removed from them. evolutionarily speaking RNA
came before DNA and protein.
Question 11.
polyribosomes
ANSWER
begin translation before transcription is complete. coupling
