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Understand a concept Get a clear explanation, see an example, then explain it yourself. Prepare for a quiz Try a short practice round. Read why each answer works. Review weak spots Recall before revealing. Revisit the ideas you flagged. Get a useful tip Find memory cues, common traps, and ways to check your thinking. Find a concept Focus your sessionAll available topics Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18 Chapter 19
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131 matching ideas
A hypothesis has to risk being wrong Spot the missing control The team can do what one part cannot Theory does not mean a wild guess The nucleus sets the identity Count the charge Three bonds, three different jobs Water is a tiny uneven magnet Why does a water strider stay up? A lake is a temperature buffer A frozen lake keeps life below A small number change, a big chemical change The chemical shock absorber Four bonds, endless shapes Build it or break it? Same glucose, very different result Plant cell wall detective Long-term fuel and waterproof walls Why a phospholipid has two personalities Sequence becomes shape becomes function The egg cannot unscramble itself The instruction molecules Match the building block Small cells exchange faster A bacterium is not an empty bag The DNA library and its doors A chromosome is still DNA Build the protein-building machines Rough and smooth have different jobs The cell has a sorting warehouse Trace one exported protein The recycling room is acidic Why a watered plant stands up Two converters, not energy creators Wall or membrane? Scaffolding that also moves A cell loses its shipping labels A fluid mosaic is a moving border Molecules keep moving at equilibrium A doorway does not always need a battery A salty bath for an animal cell A plant in fresh water A whole package crosses the border The rechargeable transfer token Does energy disappear when you move? Lower the hill, keep the destination Why hotter is not always faster A fake substrate blocks the entrance Enough product? Slow the first step Follow the carbon and the electrons The pathway outside the mitochondrion NADH carries a delivery Put the harvest in order A cycle that loads the carriers Build a proton hill, turn a turbine Oxygen waits at the end Why make lactate at all? A leaky mitochondrial membrane Two chloroplast spaces to remember Where does a tree get its added carbon? Sunlight charges two carriers The oxygen bubbles came from where? Catch carbon, spend energy, reset Cover the leaf with a box Save water without starving for carbon Do plants use respiration too? Copies are not the same as partners When is DNA copied? Line up, split, rebuild A skin cell divides One copy round, two divisions Two ways to shuffle before fertilization Half a set, not half a gene Division needs permission When chromosomes miss the split A gene is a location; alleles are versions Two carriers, one recessive outcome Every gamete gets one version Find the hidden genotype The first child does not change the next cross Pink and AB tell different stories Build the bigger cross from small ones One gene can affect many things Why one X allele can be enough Two complementary ladders run opposite ways Make the complementary DNA Each new double helix keeps one old strand Unzip, extend, seal DNA writes a message, ribosomes read it Make RNA from the template Edit the message before export A codon is not an anticodon A changed letter may or may not change the protein Why is this deletion risky? Same library, different books open A closed book cannot be read easily One switch can coordinate several bacterial genes Does a skin cell lose the insulin gene? A stuck accelerator or a broken brake Cut, join, copy, sort, read A tiny DNA sample becomes many copies Which fragment travels farther? A plasmid can carry an inserted gene A DNA match has limits Variation first, selection second Did the medicine teach bacteria? Chance, travel, and selection A storm has no favorite allele The no-change baseline Start with the recessive phenotype A boundary around gene flow Before or after fertilization? Separate in space, diverge over time A species split without a new wall Read the branching, not the lineup Can you rotate a family tree? Same ancestry or same solution? Extinction can open ecological space Two domains without a nucleus Energy source and carbon source are different Eukaryotic does not mean multicellular A short land-plant timeline Reproduction farther from standing water Digest outside, absorb inside A root and a fungus make a trade Most animals have no backbone An external suit with joints A front end for moving forward A backbone is part of a larger story An embryo gets its own protected environment Birds belong inside the reptile branch Chapter 1
A hypothesis has to risk being wrong A hypothesis is a testable explanation. A prediction says what you expect to observe if that explanation is correct. Evidence can support an explanation without proving it forever.
See an explanation or worked example “Plants grow toward a window because of light” suggests a test: change the light direction while keeping other conditions similar, then measure the growth direction.
Explain it back without copying Check my explanation against the notes →
THE MOUNTAIN IS ALWAYS HERE Biology.A mountain of ideas. 393 reading, memory, and recall notes. Repeated cards build the pile; each opens its learning note.
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THE FIELD DESK / BIOLOGY
BIOLOGY A hypothesis has to risk being wrong unfold ↗ TRY A QUESTION Explain: A hypothesis has to risk being wrong unfold ↗ KEEP THIS IDEA A tip: A hypothesis has to risk being wrong unfold ↗ BIOLOGY Spot the missing control unfold ↗ TRY A QUESTION You give one plant fertilizer and more sunlight than another. The first grows taller. Can you conclude that fertilizer caused the difference? unfold ↗ KEEP THIS IDEA A tip: Spot the missing control unfold ↗ BIOLOGY The team can do what one part cannot unfold ↗ TRY A QUESTION Explain: The team can do what one part cannot unfold ↗ KEEP THIS IDEA A tip: The team can do what one part cannot unfold ↗ BIOLOGY Theory does not mean a wild guess unfold ↗ TRY A QUESTION In science, does calling evolution a “theory” mean it has little supporting evidence? unfold ↗ KEEP THIS IDEA A tip: Theory does not mean a wild guess unfold ↗ BIOLOGY The nucleus sets the identity unfold ↗ TRY A QUESTION Explain: The nucleus sets the identity unfold ↗ KEEP THIS IDEA A tip: The nucleus sets the identity unfold ↗ BIOLOGY Count the charge unfold ↗ TRY A QUESTION An atom has 11 protons and 10 electrons. What is its net charge? unfold ↗ KEEP THIS IDEA A tip: Count the charge unfold ↗ BIOLOGY Three bonds, three different jobs unfold ↗ TRY A QUESTION Explain: Three bonds, three different jobs unfold ↗ KEEP THIS IDEA A tip: Three bonds, three different jobs unfold ↗ BIOLOGY Water is a tiny uneven magnet unfold ↗ TRY A QUESTION Explain: Water is a tiny uneven magnet unfold ↗ KEEP THIS IDEA A tip: Water is a tiny uneven magnet unfold ↗ BIOLOGY Why does a water strider stay up? unfold ↗ TRY A QUESTION Which water property helps a water strider stand on the surface, and what causes it? unfold ↗ KEEP THIS IDEA A tip: Why does a water strider stay up? unfold ↗ BIOLOGY A lake is a temperature buffer unfold ↗ TRY A QUESTION Explain: A lake is a temperature buffer unfold ↗ KEEP THIS IDEA A tip: A lake is a temperature buffer unfold ↗ BIOLOGY A frozen lake keeps life below unfold ↗ TRY A QUESTION Why does ice float, and why can that help organisms survive winter? unfold ↗ KEEP THIS IDEA A tip: A frozen lake keeps life below unfold ↗ BIOLOGY A small number change, a big chemical change unfold ↗ TRY A QUESTION A solution changes from pH 6 to pH 4. How does its hydrogen ion concentration change? unfold ↗ KEEP THIS IDEA A tip: A small number change, a big chemical change unfold ↗ BIOLOGY The chemical shock absorber unfold ↗ TRY A QUESTION Explain: The chemical shock absorber unfold ↗ KEEP THIS IDEA A tip: The chemical shock absorber unfold ↗ BIOLOGY Four bonds, endless shapes unfold ↗ TRY A QUESTION Explain: Four bonds, endless shapes unfold ↗ KEEP THIS IDEA A tip: Four bonds, endless shapes unfold ↗ BIOLOGY Build it or break it? unfold ↗ TRY A QUESTION Which process joins monomers by removing water, and which process splits a polymer by adding water? unfold ↗ KEEP THIS IDEA A tip: Build it or break it? unfold ↗ BIOLOGY Same glucose, very different result unfold ↗ TRY A QUESTION Explain: Same glucose, very different result unfold ↗ KEEP THIS IDEA A tip: Same glucose, very different result unfold ↗ BIOLOGY Plant cell wall detective unfold ↗ TRY A QUESTION A large molecule is made of glucose, but humans cannot digest it. It provides strength to a plant cell wall. What is it? unfold ↗ KEEP THIS IDEA A tip: Plant cell wall detective unfold ↗ BIOLOGY Long-term fuel and waterproof walls unfold ↗ TRY A QUESTION Explain: Long-term fuel and waterproof walls unfold ↗ KEEP THIS IDEA A tip: Long-term fuel and waterproof walls unfold ↗ BIOLOGY Why a phospholipid has two personalities unfold ↗ TRY A QUESTION Why do phospholipids form a bilayer when surrounded by water? unfold ↗ KEEP THIS IDEA A tip: Why a phospholipid has two personalities unfold ↗ BIOLOGY Sequence becomes shape becomes function unfold ↗ TRY A QUESTION Explain: Sequence becomes shape becomes function unfold ↗ KEEP THIS IDEA A tip: Sequence becomes shape becomes function unfold ↗ BIOLOGY The egg cannot unscramble itself unfold ↗ TRY A QUESTION Heat changes an enzyme’s shape so its substrate no longer fits. What happened, and why does activity fall? unfold ↗ KEEP THIS IDEA A tip: The egg cannot unscramble itself unfold ↗ BIOLOGY The instruction molecules unfold ↗ TRY A QUESTION Explain: The instruction molecules unfold ↗ KEEP THIS IDEA A tip: The instruction molecules unfold ↗ Your notes and learning progress stay safe when the pile moves.
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