Latest Posts

“You’re performing the Ames test on two known carcinogens; Benzo(a)pyrene (BaP) and methyl nitrosourea (MNU). If you treat His-Salmonella with MNU, you generate many His+ colonies. In contrast, if you treat His auxotrophic Salmonella with BaP, you generate no His prototrophs. However, if you first incubate the BaP with a liver extract before adding it to the His auxotroph Salmonella, you generate many His prototrophs. How do BaP and MNU differ?”

Biology

Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.“You’re performing the Ames test[…]

Read more

Ames Test,”demonstrates that carcinogens (cause cancer) are mutagens (alter DNA)Ames introduced a mutation into a single gene that required Histodine Biosynthesis. This strain of bacteria called His-Auxotroph.Have to add histodine b/c cells can’t make it on its own. Wanted to see what it takes to get cells from His-auxotroph to His-prototroph. These cells have very specific type of genetic mutation, so added compound must be specific mutagen that will mutate DNA at high enough frequency that mutation you’ll get will be able to restore to the original mutationif strong mutagen, lots of coloniesif weak or poor mutagen, will not see anything(a lot of compounds, if first incubated with liver extract

Biology

Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Ames Test,”demonstrates that carcinogens (cause[…]

Read more

P53,”most important tumor suppressorthe weak point of the system-the single point of failure; p53 is protein that links DNA damage to activating the checkpoint throughout the cycle (because DNA damage can occur at any time), stopping the cell cycle, repairing the damage and initiating apoptosis(interactions with ATM kinase, Mdm2, and Chkpoints1&2)In low concentration, p53 stops cell cycle. Damage unstopped b/c don’t activate repair genes (not high enough affinity) damage persists, repair genes activated, cell cycle arrest transientIf inactivated, damage accumulates

Biology

Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.P53,”most important tumor suppressorthe weak[…]

Read more