University revision · Toxicology and Pharmacology

Hormonal Therapy, Drug Resistance, and Toxicity in Oncology

Question 1 of 6 Course: Biomedical Science(Degree)

Methotrexate toxicity can be reversed by administering:

Save your progress

Did you know?

The O allele is not simply the absence of the A or B allele; it is a specific genetic variant. At the molecular level, the most common O allele (O^01) has a single nucleotide deletion (guanine) at position 261 in the coding region of the ABO gene. This deletion causes a frameshift mutation, which changes the reading frame of the subsequent genetic code. This results in the production of a truncated, non-functional glycosyltransferase enzyme that lacks catalytic activity. Because this enzyme cannot transfer a sugar (either N-acetylgalactosamine for A or galactose for B) to the H antigen precursor, the H antigen remains unmodified, resulting in the type O phenotype. Different O alleles with other mutations also exist but all result in a non-functional enzyme.

Memory tip

Break down complex topics into smaller, manageable chunks for easier recall.

Up next

Pharmacology of NSAIDs and Selective COX-2 Inhibitors

Start next revision

Top performers

lP loveness Phiri 1167

Trending revisions

Focus tracker

Time on task: 0 min