Back to Blogs
USMLE Step 1: Biochemistry
  • 08 Sep 2021

In his latest blog, Elliott Campbell MD, Dermatology Resident at Mayo Clinic, Pastest question writer and high-scoring candidate, discusses the resources, the utilization of resources and must review concepts in relation to the biochemistry section of the USMLE Step 1 exam.

The Step 1 biochemistry section is intimidating. There is a massive amount of detail and advice about how to approach this section varies considerably. This article is designed to list the resources recommended and how best to use these resources to dominate this section on test day. At the end, some absolute “need to know” concepts are provided.  

Resources for the biochemistry section

The biochemistry chapter in the front of First Aid is the gold standard resource for this section. Do not try to sit down and memorize this section by reading (more on this later). USMLE Step 1 Question banks will highlight which content is high yield and therefore are imperative for studying. I would recommend sticking to these resources alone as most of the content will be covered.

Approach to learning this content

Use your question bank first to show you which steps in the pathways have associated pathologies. More than any other section, I highly recommend the annotation approach for this section (even if you are only performing one pass through your question bank). For other sections, I generally only recommend the annotation approach if you plan to complete two passes.

The “annotation approach”

This is what I used for my Step 1 (for all sections) and has been used by many of my colleagues and mentees with great success. See the linked article for a general approach to the Step 1 curriculum. In this approach, questions are completed in tutor mode, untimed, and within categories (not on random mode). After each question, content is reviewed in First Aid. If content is missing in First Aid that was included in the question’s explanation, it should be quickly annotated into the book.

This is extremely helpful in this section as you can circle steps in pathways that repeatedly come up and/or are associated with well-known pathologic entities. I would recommend also having the online version handy to search for page numbers. Any memory devices should also be noted (“How do I remember this?”, or “Why does this make sense?”). If performing a second pass, all of the annotations are complete, but content with annotations should be reviewed again with each question. This results in a very organized framework. You will start to remember where content is located and which annotations were present. Regardless of whether you perform one or two passes through your question bank, learners should read their annotated section in First Aid all the way through at least once.

High Yield concepts

These are some of the most testable concepts; however, this only highlights some of the well-known, high yield content in this section. If you are not very familiar with the below concepts, it would be advisable to master them before test day.

  • DNA replication and repair: Know all of the specific mechanisms of the individual components, especially if there is a drug target (fluoroquinolones and topoisomerase II) or associated condition (Lynch syndrome and mismatch repair).
  • The types of mutations in DNA (frameshift): Unfortunately, they may ask for specific examples. Know the classics (First Aid and question banks).
  • Protein synthesis pathway and how antibiotics specifically target this pathway (tetracyclines hit the 30s ribosomal subunit vs. macrolides the 50s).
  • Genetic terms (dominant negative mutation): This is low hanging fruit. Make sure you really understand rather than memorize.
  • Vitamins (deficiencies higher yield than toxicities).
  • Use your question banks to determine the important steps of the urea cycle, fatty acid metabolism, fructose metabolism, and glucose metabolism (steps associated with well-established pathology).
  • High yield conditions: Muscular dystrophies, imprinting conditions, trinucleotide repeat disorders, amino acid related conditions (PKU, maple syrup urine disease, alkaptonuria, etc.), glycogen storage diseases, lysosomal storage diseases, and familial dyslipidemias.

Hope you've enjoyed reading this blog and you're now ready to blast through biochem!


Elliott Campbell - Pastest USMLE Writer

Get access to the Pastest USMLE Step 1 resource

We hope you’ve found this blog useful. Wherever you are with your Step 1 study, check out our comprehensive resource which can assist you at every stage of your test preparation. You can sign up for an amazing one-off charge of $199 which will give you access right up until your exam. Find out more>>>

  • 08 Sep 2021