UNDERSTAND THE WHY
HESI A2 Biology Study Guide
Clear explanations. Worked examples. Practice as you learn.
Start with the idea, follow an example, then check your understanding. Use the diagnostic when you want help deciding what comes next.
Life as organized, regulated systems
3 understanding checks · Optional video explanation
Why water behaves differently
1 understanding checks · Optional video explanation
Molecular classes: structure suggests function
3 understanding checks · Optional video explanation
Cell compartments and the jobs they support
5 understanding checks · Optional video explanation
Membrane transport and water balance
2 understanding checks · Optional video explanation
Enzymes and ATP-coupled work
2 understanding checks · Optional video explanation
Cellular respiration: stages and accounting
2 understanding checks · Optional video explanation
Photosynthesis: energy and carbon pathways
2 understanding checks · Optional video explanation
Cell division, chromosome sets and outcomes
4 understanding checks · Optional video explanation
DNA information: copying, RNA and protein
5 understanding checks · Optional video explanation
Alleles, expression and one-locus probability
5 understanding checks · Optional video explanation
Pathogen groups and routes of spread
4 understanding checks
Broad defenses, specific responses and immune memory
4 understanding checks · Optional video explanation
One next step is enough.
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