Practice Questions

TLS Online TPP Program

#Question id: 5844

In homologous genetic recombination, RecA protein is involved in:

#XL - T Zoology

formation of Holliday intermediates and branch migration.
introduction of negative supercoils into the recombination products.
nicking the two duplex DNA molecules to initiate the reaction.
pairing a DNA strand from one duplex DNA molecule with sequences in another duplex, regardless of complementarity.

More Questions

TLS Online TPP Program

#Question id: 5754

#XL - S Microbiology

A cell is exposed to EMS (a mutagen that causes guanine to mispair with thymine) and allowed to undergo a few rounds of DNA replication. The mutational event caused by this mutagen will be

TLS Online TPP Program

#Question id: 5755

#XL - S Microbiology

A researcher studying bacterial toxin predicts that a lysine within the toxin is important for binding it’s target cell. She used site-directed mutagenesis to change a codon for lysine (AAA) to one for asparagine (AAU). However, the mutant toxin still binds to its target cell just as well as the wild-type toxin bound and appears to have no other changes. This type of mutation is probably

TLS Online TPP Program

#Question id: 5756

#XL - S Microbiology

Type of mutation caused by an addition or deletion of a base in a polypeptide-encoding part of a gene

TLS Online TPP Program

#Question id: 5757

#XL - S Microbiology

A new E. coli mutant was tested for auxotrophy. The mutant grows on:

minimal medium (M) + arginine (A) + proline (P)

M + P + histidine (H)

M + A + H + P

but not on M or on M + A + H. The mutant requires