| Question |
Answer |
| Names of the steps in protein synthesis |
1. Initiation 2. Elongation 3. Termination |
| Sequence of events in the initiation step of protein synthesis. |
1. Initiation factors assemble the 40S ribosomal subunit with the initiator tRNA 2. mRNA and (60S?) ribosomal subunit combine with the 40S subunit. 3. Initiation factors are released. |
| Sequence of events in the elongation step of protein synthesis. |
1. Aminoacyl tRNA binds to the A site 2. Peptidyltransferase catalyzes peptide bond formation 3. Peptidyltransferase transfers growing polypeptide to aa in A site 4. Ribosome advances 3 nucleotides toward 3' end of RNA moving peptidyl RNA to P site |
| Sequence of events in the termination step of protein synthesis. |
1. Completed protein is released from ribosome. 2. Ribosome dissociates. |
| Role of ATP in protein synthesis |
ATP does tRNA Activation (charging) |
| Role of GTP in protein synthesis |
GTP does tRNA Going places (aka translocation) and Gripping |
| Role of A site in protein synthesis |
A site holds incoming Aminoacyl tRNA. |
| Role of P site in protein synthesis |
P site accomodates growing Peptide. |
| Role of E site in protein synthesis |
E site holds Empty tRNA as it Exits |
| Which post-translational modification involves removal of N or C terminal pro-peptides from zymogens to generate mature proteins? |
Trimming |
| What happens in post-translational trimming? |
removal of N or C terminal pro-peptides from zymogens to generate mature proteins |
| Which post-translational modification involves phosphorylation? |
post-translational covalent alteration |
| What happens during post-translational covalent alterations? |
Either: 1. Phosphorylation 2. Glycosylation 3. Hydroxylation |
| Which post-translational modification involves glycosylation? |
post-translational covalent alteration |
| Which post-translational modification involves hydroxylation? |
post-translational covalent alteration |
| What happens during proteasomal degradation? |
Attachment of ubiquitin to defective proteins to tag them for breakdown. |
| Ubiquitin or Ubiquinone: Proteosomal degradation |
Ubiquitin |
| Ubiquitin or Ubiquinone: Coenzyme Q in oxidative phosphorylation |
Ubiquinone |
| Where in the cell does the following occur: Fatty acid oxidation (beta-oxidation) |
Mitochondria |
| Where in the cell does the following occur: acetyl-CoA production |
Mitochondria |
| Where in the cell does the following occur: Krebs cycle |
Mitochondria |
| Where in the cell does the following occur: Glycolysis |
Cytoplasm |
| Where in the cell does the following occur: Fatty acid synthesis |
Cytoplasm |
| Where in the cell does the following occur: Hexose Monophosphate Shunt |
Cytoplasm |
| Where in the cell does the following occur: Protein Synthesis |
Rough endoplasmic reticulum in the cytoplasm |
| Where in the cell does the following occur: Steroid synthesis |
Smooth endoplasmic reticulum in the cytoplasm |
| Where in the cell does the following occur: Gluconeogenesis |
Pathway has steps in the mitochondria and in the cytoplasm |
| Where in the cell does the following occur: Urea cycle |
Pathway has steps in the mitochondria and in the cytoplasm |
| Where in the cell does the following occur: Heme synthesis |
Pathway has steps in the mitochondria and in the cytoplasm |
