Chapter 15
Amino acids are linked together via this type of bond.
What are peptide bonds?
What is a DNA binding protein?
This is what occurs when a thymine base (T) is replaced by a guanine base (G) during replication of a wild type strand due to mutation, for example.
(hint: transition or transversion)
What is a transversion?
This site on the ribosome is where the new tRNA carrying the fMet amino acid binds.
What is the P (peptidyl) site?
Lac IS
What is the super repressor mutant on the lac operon?
This is the term for the fact that each amino acid can be represented by more than one codon.
What is degenerate?
A Pribnow box and TTGACA are examples of these, in prokaryotes.
What are consensus sequences?
This is the type of mutation that occurs when an amino acid codon mutates to a stop codon, halting the translation of the polypeptide.
What is a nonsense mutation?
These two functional groups are present in all amino acids.
What are the amino group and the carboxyl group?
This mechanism is used to repair thymine dimers in DNA. (There are two mechanisms; either answer will suffice.)
What are direct repair (photoreactivation) or nucleotide excision repair (dark repair)?
These scientists used auxotrophic mutants to discover biochemical pathways, coming up with the "one gene, one protein" hypothesis.
Who are Beadle and Tatum?
This occurs when tryptophan levels are high; the trp operon folds into a loop structure, with region 3 pairing with region 4 to stop an ongoing transcription.
What is attenuation?
This is what happens after a mutation has occurred; then, another mutation changes the amino acid back exactly to the wild type.
What is a true reverse mutation?
This type of molecule can be transcribed and translated at the same time in a prokaryote.
This protein helps transport lactose into the cell to be broken down by the lac operon.
What is permease?
This refers to the "relaxed" nature of the third codon.
What is wobble?
These types of genes are always expressed and the enzymes produced from these genes are always produced.
What are constitutive genes?
This is the process by which cytosine can become uracil, due to the removal of the NH2 group and replacement with a double bonded O.
What is deamination?
In translation, this portion of the tRNA molecule links to the amino acid during tRNA charging.
What is the acceptor stem?
Acridine and ethidium bromide belong to this category of chemical mutagens.
What is intercalating agents?
This is the sequence surrounding the start codon in eukaryotic translation.
What is the Kozak sequence?
In the lac operon, this happens to levels of cAMP (cyclic AMP) when levels of glucose are low and lactose is present.
What is that levels of cAMP are high, and it binds to CAP and helps facilitate binding of RNA polymerase to start transcription?
This is a base analog for thymine.
What is 5-bromouracil?
This type of mutation occurred here:
Wild Type: Phe Leu Pro Thr Val Thr Thr Arg Trp
Mutant: Phe Leu His His Gly Asp Asp Thr Val
What is a frameshift mutation?
This is when a mutation occurs and then another mutation occurs in the same gene, but at a different site from the original mutation, but compensating for the first mutation.
What is an intragenic suppressor mutation?