Gene Expression

Question 1

Protein synthesis was identified with cytosolic RNA-protein complexes called …

Answer 1

Ribosomes

Question 2

Protein synthesis is not directly directed by DNA

Answer 2

RNA is the intermediary

Question 3

DNA structure and bases in DNA

Answer 3

Antiparallel double stranded helix;
Sequence in 5’ to 3’ direction;
4 diffferent bases:
2 purines - guanine and adenine;
2 pyrimidines - cytosine and thymine 
G and C base pair stronger (more H bonds);

Question 4

RNA structure and bases

Answer 4

Single stranded;
Right handed helical structure;
Base-stacking and van der waals forces;
Very strong between purines;
RNA more reactive than DNA

Question 5

3 major types of RNA

Answer 5

Ribososmal RNA - 2/3 of ribosome;
Transfer RNA - delivers amino acids to ribosomes;
MRNA - nucleotide sequences that direct protein synthesis;

All cellular RNA are transcribed from DNA templates;

Question 6

Production of RNA from DNA is carried out by

Answer 6

DNA-dependent RNA polymerases

Question 7

RNA polymerase

Answer 7

Couples together ribonucleotide triphosphates (NTP, ATP, CTP, GTP, UTP);
On DNA template;
Driven by release and hydrolysis of PPi;