Large doses of antibiotics given to fight an infection are likely to destroy bacteria that produce vitamin k. in which digestive organ do we find such beneficial bacteria?
a: stomach
b: large intestine
c: liver

I'm guessing Liver.
If it was in the stomach, we wouldn't get belly aches. If it were in the large intestine, we wouldn't poop. So that's my guess.

Six amino acids have side chains that are polar but not charged. these are serine (ser), threonine (thr), cysteine (cys), asparagine (asn), glutamine (gln), and tyrosine (tyr). these amino acids are usually found at the surface of proteins, as discussed in the proteins 2 module.