How DNA stores information, how it copies itself before a cell divides, and how the cell reads that information through transcription and translation, the way HESI A2 Biology questions test it.
ObjectiveB.4.1Read6 minExam weightMolecular Biology ≈ 16% of Biology
This lesson is part of the full Study Guide
Unlock every lesson, unit, and quiz across every subject. The Biology molecular biology unit is included.
Describe the structure of DNA and explain the base pairing rule that makes replication possible.
Walk through replication, transcription and translation in the correct order, naming the molecule and enzyme at each step.
Read a codon table well enough to translate a short mRNA sequence into an amino acid chain.
What the lesson concludes
DNA is a double helix of two antiparallel strands held together by base pairing: adenine with thymine, guanine with cytosine.
Replication is semiconservative. Each new DNA molecule keeps one original strand and builds one new strand against it.
The central dogma runs one direction for normal gene expression: DNA to RNA to protein, called transcription then translation.
RNA differs from DNA in three ways worth memorising: it is single stranded, it carries ribose instead of deoxyribose, and it substitutes uracil for thymine.
A codon is three mRNA bases that specify one amino acid. An anticodon on tRNA is the complementary three bases that pair with it during translation.