Antibiotic resistance can evolve rapidly in bacterial popula…
Antibiotic resistance can evolve rapidly in bacterial populations. Suppose that a type of bacterial infection is normally treated with antibiotic A. A person who has an infection with this type of bacteria takes antibiotic A, but it has no effect. It is determined that the bacteria causing their infection have a new allele that makes them resistant to the antibiotic because it cannot bind to the normal target molecule in the bacteria. How did the bacteria become resistant to the antibiotic? Side note: Fortunately for the person with the infection, it turns out there is another antibiotic that can be used to treat the infection, so the person recovers and is fine.
Read DetailsSuppose that a reaction in which a chemical bond is broken h…
Suppose that a reaction in which a chemical bond is broken has ΔG of – 5.2 kcal/mol. Forming another bond has ΔG of + 3.3 kcal/mol. Could these two reactions be coupled so the energy released by one reaction is used to drive the other?
Read DetailsThe template strand of a DNA molecule includes the sequence…
The template strand of a DNA molecule includes the sequence 3′ A T T C G 5′. The complementary DNA strand would be [a]. If this section of the DNA was used to make RNA, the sequence of the mRNA would be [b]. During DNA or RNA synthesis, the growing strand is elongated as phosphodiester bonds are formed between nucleotides. During DNA synthesis, this is carried out by [c], but during RNA synthesis, it is carried out by [d].
Read DetailsA point mutation changes a codon from 5′ UGG 3′ to 5′ UGU 3’…
A point mutation changes a codon from 5′ UGG 3′ to 5′ UGU 3′. This changes the amino acid from tryptophan (which is nonpolar) to cysteine (which is polar). What is the most likely impact of this mutation on the protein’s structure and function?
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