<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #ffffff;
      color: #0f172a;
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 10px;
      gap: 8px;
      width: 100%;
      user-select: none;
    }

    .controls {
      width: 100%;
      max-width: 600px;
      display: flex;
      flex-direction: column;
      gap: 6px;
      background: #f8fafc;
      padding: 8px 12px;
      border-radius: 8px;
      border: 1px solid #e2e8f0;
    }

    .slider-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 12px;
    }

    .slider-label {
      font-size: 13px;
      font-weight: 600;
      color: #334155;
      white-space: nowrap;
    }

    input[type=range] {
      flex: 1;
      height: 6px;
      accent-color: #0284c7;
      cursor: pointer;
    }

    .presets {
      display: flex;
      gap: 6px;
      justify-content: center;
    }

    .btn-preset {
      font-size: 11px;
      font-weight: 600;
      padding: 4px 10px;
      border-radius: 4px;
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #475569;
      cursor: pointer;
      transition: all 0.2s ease;
    }

    .btn-preset.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
    }

    .comparison-grid {
      display: grid;
      grid-template-columns: 1fr 1.6fr;
      gap: 8px;
      width: 100%;
      max-width: 600px;
    }

    @media (max-width: 480px) {
      .comparison-grid {
        grid-template-columns: 1fr;
      }
    }

    .panel {
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      position: relative;
    }

    .panel-tag {
      font-size: 11px;
      font-weight: 700;
      letter-spacing: 0.5px;
      text-transform: uppercase;
      color: #64748b;
      margin-bottom: 4px;
    }

    .canvas-container {
      width: 100%;
      height: 140px;
      position: relative;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    canvas {
      width: 100%;
      height: 100%;
      display: block;
    }

    .stats-card {
      width: 100%;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 4px;
      margin-top: 6px;
    }

    .stat-item {
      background: #ffffff;
      padding: 4px 6px;
      border-radius: 6px;
      border: 1px solid #e2e8f0;
      text-align: center;
    }

    .stat-label {
      font-size: 10px;
      color: #64748b;
      font-weight: 600;
    }

    .stat-val {
      font-size: 12px;
      font-weight: 700;
      color: #0f172a;
    }

    .stat-val.highlight {
      color: #0284c7;
    }

    .fick-bar-box {
      width: 100%;
      max-width: 600px;
      background: #f0f9ff;
      border: 1px solid #bae6fd;
      border-radius: 8px;
      padding: 8px 12px;
      display: flex;
      flex-direction: column;
      gap: 4px;
    }

    .fick-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 11px;
      font-weight: 700;
      color: #0369a1;
    }

    .bar-bg {
      height: 10px;
      background: #e0f2fe;
      border-radius: 5px;
      overflow: hidden;
      position: relative;
    }

    .bar-fill {
      height: 100%;
      background: linear-gradient(90deg, #0284c7, #0d9488);
      width: 2%;
      border-radius: 5px;
      transition: width 0.1s linear;
    }
  </style>
</head>
<body>

  
  <div class="controls">
    <div class="slider-row">
      <span class="slider-label">Membrane Folding:</span>
      <input type="range" id="foldSlider" min="1" max="50" value="1" step="1">
      <span class="slider-label" id="multVal" style="color:#0284c7; min-width: 38px;">1×</span>
    </div>
    <div class="presets">
      <button class="btn-preset active" data-val="1">Flat Solid (1×)</button>
      <button class="btn-preset" data-val="15">Moderate Folds (15×)</button>
      <button class="btn-preset" data-val="50">Microvilli / Lamellae (50×)</button>
    </div>
  </div>

  
  <div class="comparison-grid">
    
    <div class="panel">
      <span class="panel-tag">Solid Block (10×10×10 cm)</span>
      <div class="canvas-container">
        <svg viewBox="0 0 160 130" width="100%" height="100%">
          <defs>
            <linearGradient id="cubeTop" x1="0" y1="0" x2="1" y2="1">
              <stop offset="0%" stop-color="#93c5fd" />
              <stop offset="100%" stop-color="#60a5fa" />
            </linearGradient>
            <linearGradient id="cubeLeft" x1="0" y1="0" x2="1" y2="1">
              <stop offset="0%" stop-color="#3b82f6" />
              <stop offset="100%" stop-color="#2563eb" />
            </linearGradient>
            <linearGradient id="cubeRight" x1="0" y1="0" x2="1" y2="1">
              <stop offset="0%" stop-color="#1d4ed8" />
              <stop offset="100%" stop-color="#1e40af" />
            </linearGradient>
          </defs>
          
          <polygon points="80,25 130,50 80,75 30,50" fill="url(#cubeTop)" stroke="#1e3a8a" stroke-width="1.5" />
          <polygon points="30,50 80,75 80,120 30,95" fill="url(#cubeLeft)" stroke="#1e3a8a" stroke-width="1.5" />
          <polygon points="80,75 130,50 130,95 80,120" fill="url(#cubeRight)" stroke="#1e3a8a" stroke-width="1.5" />
          
          <text x="50" y="32" font-size="10" font-weight="bold" fill="#1e3a8a">10 cm</text>
          <text x="110" y="32" font-size="10" font-weight="bold" fill="#1e3a8a">10 cm</text>
          <text x="135" y="88" font-size="10" font-weight="bold" fill="#1e3a8a">10 cm</text>
        </svg>
      </div>
      <div class="stats-card">
        <div class="stat-item">
          <div class="stat-label">Area</div>
          <div class="stat-val">600 cm²</div>
        </div>
        <div class="stat-item">
          <div class="stat-label">Volume</div>
          <div class="stat-val">1,000 cm³</div>
        </div>
        <div class="stat-item" style="grid-column: span 2;">
          <div class="stat-label">SA : V Ratio</div>
          <div class="stat-val">0.6 : 1</div>
        </div>
      </div>
    </div>

    
    <div class="panel">
      <span class="panel-tag">Folded Surface Cross-Section</span>
      <div class="canvas-container">
        <canvas id="simCanvas"></canvas>
      </div>
      <div class="stats-card">
        <div class="stat-item">
          <div class="stat-label">Effective Area</div>
          <div class="stat-val highlight" id="rightArea">600 cm²</div>
        </div>
        <div class="stat-item">
          <div class="stat-label">Volume</div>
          <div class="stat-val">1,000 cm³</div>
        </div>
        <div class="stat-item" style="grid-column: span 2;">
          <div class="stat-label">SA : V Ratio</div>
          <div class="stat-val highlight" id="rightRatio">0.6 : 1</div>
        </div>
      </div>
    </div>
  </div>

  
  <div class="fick-bar-box">
    <div class="fick-header">
      <span>Fick's Law: Rate ∝ Area × (ΔC / Δx)</span>
      <span id="fluxMult" style="font-size:12px; font-weight:800; color:#0284c7;">1.0× Flux</span>
    </div>
    <div class="bar-bg">
      <div class="bar-fill" id="fluxBar"></div>
    </div>
  </div>

  <script>
    const slider = document.getElementById('foldSlider');
    const multVal = document.getElementById('multVal');
    const rightArea = document.getElementById('rightArea');
    const rightRatio = document.getElementById('rightRatio');
    const fluxMult = document.getElementById('fluxMult');
    const fluxBar = document.getElementById('fluxBar');
    const presetBtns = document.querySelectorAll('.btn-preset');
    const canvas = document.getElementById('simCanvas');
    const ctx = canvas.getContext('2d');

    let particles = [];
    const NUM_PARTICLES = 50;

    function resizeCanvas() {
      const rect = canvas.getBoundingClientRect();
      canvas.width = rect.width * window.devicePixelRatio;
      canvas.height = rect.height * window.devicePixelRatio;
      ctx.scale(window.devicePixelRatio, window.devicePixelRatio);
    }
    window.addEventListener('resize', resizeCanvas);
    resizeCanvas();

    // Initialize particles for diffusion visual
    for (let i = 0; i < NUM_PARTICLES; i++) {
      particles.push({
        x: Math.random(),
        y: Math.random() * 0.35,
        vx: (Math.random() - 0.5) * 0.002,
        vy: 0.002 + Math.random() * 0.003
      });
    }

    function updateMetrics(val) {
      multVal.textContent = val + '×';
      const area = 600 * val;
      rightArea.textContent = area.toLocaleString() + ' cm²';
      const ratio = (0.6 * val).toFixed(1);
      rightRatio.textContent = ratio + ' : 1';
      fluxMult.textContent = val.toFixed(1) + '× Flux';
      fluxBar.style.width = Math.min(100, Math.max(2, (val / 50) * 100)) + '%';

      presetBtns.forEach(btn => {
        btn.classList.toggle('active', parseInt(btn.dataset.val) === parseInt(val));
      });
    }

    slider.addEventListener('input', (e) => {
      updateMetrics(parseFloat(e.target.value));
    });

    presetBtns.forEach(btn => {
      btn.addEventListener('click', () => {
        const v = parseFloat(btn.dataset.val);
        slider.value = v;
        updateMetrics(v);
      });
    });

    // Render loop
    function render() {
      const w = canvas.width / window.devicePixelRatio;
      const h = canvas.height / window.devicePixelRatio;
      const foldK = parseFloat(slider.value);

      ctx.clearRect(0, 0, w, h);

      const baseY = h * 0.72;
      const numFingers = Math.max(1, Math.round(1 + (foldK - 1) * 0.3));
      const fingerHeight = Math.min(h * 0.55, 6 + (foldK - 1) * 1.5);

      // Draw Tissue Interior (Basement / Blood stream)
      ctx.fillStyle = '#f0fdf4';
      ctx.beginPath();
      ctx.rect(0, baseY, w, h - baseY);
      ctx.fill();

      // Draw lumen / exterior background
      ctx.fillStyle = '#f0f9ff';
      ctx.fillRect(0, 0, w, baseY);

      // Draw Folded Epithelial Membrane Path
      ctx.beginPath();
      ctx.moveTo(0, baseY);

      const segmentW = w / numFingers;
      for (let i = 0; i < numFingers; i++) {
        const x0 = i * segmentW;
        const x1 = x0 + segmentW * 0.25;
        const x2 = x0 + segmentW * 0.5;
        const x3 = x0 + segmentW * 0.75;
        const x4 = (i + 1) * segmentW;

        if (foldK === 1) {
          ctx.lineTo(x4, baseY);
        } else {
          ctx.lineTo(x1, baseY);
          ctx.bezierCurveTo(x1, baseY - fingerHeight, x3, baseY - fingerHeight, x3, baseY);
          ctx.lineTo(x4, baseY);
        }
      }

      ctx.lineTo(w, h);
      ctx.lineTo(0, h);
      ctx.closePath();

      // Fill folded tissue
      ctx.fillStyle = '#e0f2fe';
      ctx.fill();

      // Stroke membrane border
      ctx.lineWidth = 3;
      ctx.strokeStyle = '#0284c7';
      ctx.stroke();

      // Draw Solute Diffusion Particles
      const speedMult = 0.5 + (foldK / 50) * 2.5;
      particles.forEach(p => {
        p.y += p.vy * speedMult;
        p.x += p.vx;
        if (p.x < 0) p.x = 1;
        if (p.x > 1) p.x = 0;
        if (p.y > 0.9) p.y = 0.05;

        const px = p.x * w;
        const py = p.y * h;

        ctx.beginPath();
        ctx.arc(px, py, 2.5, 0, Math.PI * 2);
        ctx.fillStyle = py > baseY - fingerHeight ? '#0d9488' : '#0284c7';
        ctx.fill();
      });

      // Directional Transport Arrows
      const arrowCount = Math.min(12, Math.max(2, Math.round(foldK * 0.24)));
      ctx.fillStyle = '#0284c7';
      for (let i = 0; i < arrowCount; i++) {
        const ax = (i + 0.5) * (w / arrowCount);
        const ay = 14;
        ctx.beginPath();
        ctx.moveTo(ax, ay);
        ctx.lineTo(ax - 3, ay - 5);
        ctx.lineTo(ax + 3, ay - 5);
        ctx.closePath();
        ctx.fill();
      }

      requestAnimationFrame(render);
    }

    updateMetrics(1);
    render();
  </script>
</body>
</html>

Anatomical Adaptations: Structural Modifications for Survival

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, sans-serif;
      background: #f8fafc;
      color: #1e293b;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
    }

    .toolbar {
      display: flex;
      gap: 6px;
      margin-bottom: 12px;
      background: #e2e8f0;
      padding: 3px;
      border-radius: 8px;
    }

    .btn {
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      border: none;
      background: transparent;
      color: #64748b;
      border-radius: 6px;
      cursor: pointer;
      transition: all 0.2s ease;
    }

    .btn.active {
      background: #ffffff;
      color: #0284c7;
      box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    }

    .grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 8px;
      width: 100%;
      max-width: 600px;
    }

    .bone-card {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 10px;
      padding: 10px 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      cursor: pointer;
      transition: border-color 0.2s ease, box-shadow 0.2s ease;
    }

    .bone-card:hover, .bone-card.selected {
      border-color: #38bdf8;
      box-shadow: 0 4px 12px rgba(2, 132, 199, 0.08);
    }

    .label-title {
      font-size: 14px;
      font-weight: 700;
      color: #0f172a;
      margin-bottom: 2px;
    }

    .label-sub {
      font-size: 11px;
      font-weight: 600;
      color: #64748b;
      margin-bottom: 8px;
    }

    .svg-container {
      width: 100%;
      height: 120px;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }

    .label-tag {
      margin-top: 8px;
      font-size: 11px;
      font-weight: 700;
      padding: 3px 6px;
      border-radius: 4px;
      background: #f1f5f9;
      color: #0369a1;
    }

    /* Stress vector animations */
    .stress-vector {
      opacity: 0;
      transition: opacity 0.3s ease;
    }

    .show-stress .stress-vector {
      opacity: 1;
    }

    .pulse-strut {
      animation: strutGlow 2s infinite ease-in-out;
    }

    @keyframes strutGlow {
      0%, 100% { stroke: #0284c7; stroke-width: 2.5; }
      50% { stroke: #38bdf8; stroke-width: 3.5; }
    }

    .vector-arrow {
      animation: pushVector 1.5s infinite alternate ease-in-out;
    }

    @keyframes pushVector {
      0% { transform: translateY(0); }
      100% { transform: translateY(3px); }
    }

    .torque-arrow {
      animation: rotateVector 2s infinite alternate ease-in-out;
      transform-origin: 50% 50%;
    }

    @keyframes rotateVector {
      0% { transform: rotate(-5deg); }
      100% { transform: rotate(5deg); }
    }
  </style>
</head>
<body>

  <div class="toolbar">
    <button class="btn active" id="btnStruct" onclick="setMode('structure')">Architecture</button>
    <button class="btn" id="btnStress" onclick="setMode('stress')">Stress Vectors</button>
  </div>

  <div class="grid" id="boneGrid">
    
    
    <div class="bone-card selected" onclick="selectCard(this)">
      <div class="label-title">🦅 Avian</div>
      <div class="label-sub">Pneumatic</div>
      <div class="svg-container">
        <svg viewBox="0 0 100 100">
          <defs>
            <marker id="arr-blue" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="4" markerHeight="4" orient="auto-start-reverse">
              <path d="M 0 1.5 L 8 5 L 0 8.5 z" fill="#0284c7"/>
            </marker>
          </defs>

          
          <circle cx="50" cy="50" r="38" fill="#ffffff" stroke="#334155" stroke-width="3" />
          
          
          <line x1="30" y1="20" x2="70" y2="80" stroke="#0284c7" stroke-width="2" class="pulse-strut" />
          <line x1="70" y1="20" x2="30" y2="80" stroke="#0284c7" stroke-width="2" class="pulse-strut" />
          <line x1="16" y1="50" x2="84" y2="50" stroke="#0284c7" stroke-width="2" class="pulse-strut" />
          <line x1="30" y1="80" x2="70" y2="80" stroke="#0284c7" stroke-width="1.5" />
          <line x1="30" y1="20" x2="70" y2="20" stroke="#0284c7" stroke-width="1.5" />
          
          
          <g class="stress-vector">
            <path d="M 12 30 Q 50 18 88 30" fill="none" stroke="#0284c7" stroke-width="2" stroke-dasharray="3 2" />
            <line x1="50" y1="2" x2="50" y2="12" stroke="#0284c7" stroke-width="2.5" marker-end="url(#arr-blue)" />
            <line x1="50" y1="98" x2="50" y2="88" stroke="#0284c7" stroke-width="2.5" marker-end="url(#arr-blue)" />
          </g>
        </svg>
      </div>
      <div class="label-tag">Light + Stiff</div>
    </div>

    
    <div class="bone-card" onclick="selectCard(this)">
      <div class="label-title">🦌 Mammal</div>
      <div class="label-sub">Compact Cortex</div>
      <div class="svg-container">
        <svg viewBox="0 0 100 100">
          
          <circle cx="50" cy="50" r="38" fill="#94a3b8" stroke="#334155" stroke-width="3" />
          
          <circle cx="50" cy="50" r="22" fill="#f8fafc" stroke="#64748b" stroke-width="1.5" />
          
          
          <circle cx="45" cy="46" r="3" fill="#cbd5e1" />
          <circle cx="55" cy="52" r="4" fill="#cbd5e1" />
          <circle cx="48" cy="56" r="2.5" fill="#cbd5e1" />

          
          <g class="stress-vector vector-arrow">
            <line x1="30" y1="2" x2="30" y2="14" stroke="#0284c7" stroke-width="3" marker-end="url(#arr-blue)" />
            <line x1="70" y1="2" x2="70" y2="14" stroke="#0284c7" stroke-width="3" marker-end="url(#arr-blue)" />
            <line x1="30" y1="98" x2="30" y2="86" stroke="#0284c7" stroke-width="3" marker-end="url(#arr-blue)" />
            <line x1="70" y1="98" x2="70" y2="86" stroke="#0284c7" stroke-width="3" marker-end="url(#arr-blue)" />
          </g>
        </svg>
      </div>
      <div class="label-tag">Weight Support</div>
    </div>

    
    <div class="bone-card" onclick="selectCard(this)">
      <div class="label-title">🐾 Mole</div>
      <div class="label-sub">Hyperostotic</div>
      <div class="svg-container">
        <svg viewBox="0 0 100 100">
          
          <ellipse cx="50" cy="50" rx="44" ry="28" fill="#64748b" stroke="#1e293b" stroke-width="3.5" />
          
          <ellipse cx="50" cy="50" rx="12" ry="7" fill="#f8fafc" stroke="#475569" stroke-width="1.5" />

          
          <g class="stress-vector torque-arrow">
            <path d="M 12 75 C 8 40, 25 15, 50 15" fill="none" stroke="#0284c7" stroke-width="3" marker-end="url(#arr-blue)" />
            <path d="M 88 25 C 92 60, 75 85, 50 85" fill="none" stroke="#0284c7" stroke-width="3" marker-end="url(#arr-blue)" />
          </g>
        </svg>
      </div>
      <div class="label-tag">High Torque</div>
    </div>

  </div>

  <script>
    function setMode(mode) {
      const grid = document.getElementById('boneGrid');
      const btnStruct = document.getElementById('btnStruct');
      const btnStress = document.getElementById('btnStress');

      if (mode === 'stress') {
        grid.classList.add('show-stress');
        btnStress.classList.add('active');
        btnStruct.classList.remove('active');
      } else {
        grid.classList.remove('show-stress');
        btnStruct.classList.add('active');
        btnStress.classList.remove('active');
      }
    }

    function selectCard(card) {
      document.querySelectorAll('.bone-card').forEach(c => c.classList.remove('selected'));
      card.classList.add('selected');
    }
  </script>
</body>
</html>

Behavioural Adaptations: Innate and Learned Survival Strategies

Physiological Adaptations: Biochemical and Metabolic Modifications

Analogous vs Homologous Structures and Convergent Evolution

Xerophytic Adaptations in Plants to Conserve Water

Hydrophytic and Halophytic Adaptations in Plants

Haemoglobin Adaptations in Different Species and Environments

Thermoregulatory Adaptations: Bergmann's and Allen's Rules

science

Biological Adaptations: Anatomical, Physiological, and Behavioural

Principles of Natural Selection and Differential Reproductive Success

Directional Selection: Antibiotic Resistance and Peppered Moths

Stabilising Selection: Human Birth Mass and Phenotypic Constancy

Disruptive Selection: Bimodal Distributions and Polymorphism

Allopatric Speciation: Geographical Isolation and Adaptive Divergence

Sympatric Speciation: Polyploidy, Behavioural, and Ecological Isolation

Genetic Drift, Population Bottlenecks, and the Founder Effect

The Hardy-Weinberg Principle: Assumptions, Calculations, and Testing

Adaptive Radiation and the Generation of Global Biodiversity

Synoptic Case Studies in Evolutionary Adaptations and Diversity

Natural Selection, Speciation, and Population Genetics

Surface Area to Volume Ratio and Metabolic Scaling

Gas Exchange in Single-Celled Organisms

Gas Exchange in Insects: Spiracles, Tracheae, and Tracheoles

Limiting Water Loss in Terrestrial Insects

Gas Exchange in Fish: Gill Filaments and Lamellae

The Countercurrent Exchange Mechanism in Bony Fish

Gas Exchange in Dicotyledonous Leaves: Mesophyll and Stomata

Stomatal Opening and Closing Mechanism in Guard Cells

Gas Exchange Mechanisms in Animals and Plants

Human Respiratory System: Gross and Microscopic Anatomy

The Alveoli: Specialised Adaptations for Human Gas Exchange

Mechanism of Ventilation: Inspiration and Expiration

Spirometry: Pulmonary Ventilation Rate and Tidal Volumes

Dissection of a Mammalian Lung and Gas Exchange Structures

Pathology of Lung Diseases: Emphysema, Asthma, and Fibrosis

Epidemiology and Risk Factors for Pulmonary Diseases

Comparative Analysis of Gas Exchange Across Phyla

Human Gas Exchange, Ventilation, and Respiratory Pathology

The Need for a Circulatory System in Active Animals

Single versus Double and Open versus Closed Circulations

Haemoglobin Structure and Quaternary Organisation

Oxygen Dissociation Curve and Cooperative Binding

The Bohr Effect and CO2-Induced Affinity Changes

Principles of Circulation and Haemoglobin Physiology

The Biological Species Concept and Reproductive Isolation

The Binomial System of Nomenclature: Rules and Conventions

Hierarchical Taxonomic Ranks: Domain to Species

Courtship Behaviour and Species Recognition Mechanisms

Historical Classification Based on Observable Phenotypes

Analogous versus Homologous Structures and Convergent Evolution

Phylogenetic Classification and Evolutionary Trees

Principles of Taxonomy and Evolutionary Classification

Physiological Adaptations: Biochemical and Metabolic Processes

Natural Selection: Differential Reproductive Success Principles

Directional Selection: Antibiotic Resistance and Morphology

Stabilising Selection: Human Birth Mass and Optimum Phenotypes

Investigating the Effect of Antibiotics on Bacterial Growth

Adaptations and Modes of Natural Selection

Allopatric Speciation: Geographical Isolation and Divergence

Sympatric Speciation: Reproductive Isolation in Shared Habitats

Genetic Drift and the Founder Effect in Small Populations

The Hardy-Weinberg Principle: Assumptions and Equations

Investigating Variation Using Mean and Standard Deviation

Using Student's t-Test to Compare Biological Means

The Chi-Squared Test for Categorical Biological Frequencies

Speciation and the Generation of Global Biodiversity

Speciation, Population Genetics, and Evolutionary Analysis

BIO-1.6

BIO-1.6

Aligned learning resources

Related diagrams