STEM Knowledge Library

Visual articles with free 2D maps, structure annotations, tags, categories, and relationship links across STEM subjects.

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Plant Biology

Chloroplast and Photosynthesis Structures

Map the membranes, thylakoid stacks, stroma, and products that make chloroplasts the site of photosynthesis.

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Annotated teaching image of a chloroplast with thylakoids, stroma, DNA, starch, and oxygen release.
1

Light direction

Light energy enters the chloroplast and drives the light reactions.

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Annotated teaching image of alveoli, capillaries, red blood cells, and the blood-air barrier.
Alveoli and Gas Exchange
Study how thin alveolar walls, capillaries, and red blood cells support fast oxygen and carbon dioxide exchange.
BiologyHuman Physiology
10 min / BeginnerRead
Annotated teaching image of an antibody binding antigen epitopes.
Antibody and Antigen Binding
Inspect how the Y-shaped antibody uses flexible binding arms to recognize an antigen epitope.
BiologyImmunology
9 min / BeginnerRead
Annotated teaching image of a bacterial cell with capsule, wall, membrane, nucleoid, plasmid, pili, and flagellum.
Bacterial Cell Structure
Explore the major features of a prokaryotic cell, including the envelope, nucleoid, plasmids, pili, and flagellum.
BiologyMicrobiology
10 min / BeginnerRead
Annotated teaching image of CRISPR-Cas9 binding and cutting target DNA.
CRISPR-Cas9 Gene Editing
Visualize how guide RNA directs Cas9 to a DNA target so a precise cut can start a repair outcome.
BiologyGenetics
12 min / IntermediateRead
Annotated teaching image of a chloroplast with thylakoids, stroma, DNA, starch, and oxygen release.
Chloroplast and Photosynthesis Structures
Map the membranes, thylakoid stacks, stroma, and products that make chloroplasts the site of photosynthesis.
BiologyPlant Biology
12 min / BeginnerRead
Annotated teaching image of a DNA replication fork with helicase, leading strand, lagging strand, and primers.
DNA Replication Fork
Follow the enzymes and strand geometry that let DNA copy both strands from a moving fork.
BiologyGenetics
11 min / IntermediateRead
Annotated teaching image of an enzyme active site binding substrate and releasing products.
Enzyme Catalysis and Active Site
Connect enzyme shape, substrate binding, catalytic residues, and product release in one visual map.
BiologyBiochemistry
9 min / BeginnerRead
Annotated teaching image of a glomerulus, Bowman's capsule, podocytes, and filtration spaces.
Glomerulus and Filtration
Trace how blood pressure, capillaries, podocytes, and Bowman's capsule form the kidney's filtration barrier.
BiologyHuman Physiology
11 min / IntermediateRead
Annotated teaching image of homologous chromosomes crossing over during meiosis.
Meiosis Crossing Over
Map homologous chromosomes, chromatids, and exchange points that create new allele combinations.
BiologyGenetics
10 min / IntermediateRead
Annotated teaching image of a neuron synapse releasing neurotransmitters.
Neuron Synapse and Neurotransmitter Release
See how synaptic vesicles release chemical signals across a narrow cleft and activate receptors on the next cell.
BiologyNeuroscience
10 min / BeginnerRead
Annotated teaching image of a plant vascular bundle with xylem, phloem, cambium, and transport arrows.
Plant Vascular Bundle Transport
Inspect how xylem, phloem, cambium, and surrounding tissues organize water and sugar movement in plants.
BiologyPlant Biology
11 min / BeginnerRead
Annotated teaching image of a plant root tip with growth zones and mitosis features.
Root Tip and Mitosis
Use a root tip to connect plant growth zones with the cell division stages visible near the meristem.
BiologyPlant Biology
10 min / BeginnerRead