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Biology, explained clearly
Short, accurate explainers for the topics students get stuck on, each with a quiz and a worked example.
EnergyCellular Respiration Explained: Stages and ATPHow cells turn the glucose in food into the energy that powers everything they do.Read the explainer Plants and energyPhotosynthesis Explained: Equation and StagesHow plants use light energy to build sugars from water and carbon dioxide.Read the explainer CellsMitosis vs Meiosis: Differences, Stages, TableTwo ways cells divide. One copies the cell, the other makes the cells for reproduction.Read the explainer GeneticsDNA Replication Explained Step by StepHow a cell copies its DNA with high accuracy before it divides.Read the explainer GeneticsHow to Do a Punnett Square: Step-by-Step GuideA simple grid that predicts the chances of offspring inheriting each trait.Read the explainer Biological moleculesEnzymes Explained: Active Site, Temperature and pHThe proteins that make the chemistry of life fast enough to keep you alive.Read the explainer Cell transportOsmosis vs Diffusion vs Active TransportThree ways substances cross cell membranes, and how to tell them apart in an exam.Read the explainer GeneticsTranscription and Translation ExplainedHow the instructions in DNA become the proteins that do the work in your cells.Read the explainer EvolutionNatural Selection Explained With a Simple ExampleHow populations change over generations without anything planning it.Read the explainer Body systemsThe Nervous System and Reflex Arc ExplainedHow your body detects something and responds, sometimes before you've even noticed.Read the explainer
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