<!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="1:1">
  <title>Crossing Over</title>
  <style>
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    html, body {
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      height: 100%;
      font-family: system-ui, -apple-system, sans-serif;
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      color: #1e2945;
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      color: #64748b;
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    .step-btn.active {
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    .footer {
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      border-radius: 6px;
      border: 1px solid #e2e8f0;
    }
  </style>
</head>
<body>

  <div class="nav-bar">
    <button class="step-btn active" id="btn-0">1 · Synapsis</button>
    <button class="step-btn" id="btn-1">2 · Chiasma</button>
    <button class="step-btn" id="btn-2">3 · Result</button>
  </div>

  <div class="stage-container">
    <svg viewBox="0 0 360 270" id="diagram">
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        <text x="180" y="248" font-size="13" font-weight="700" fill="#64748b" text-anchor="middle">Homologous Pair</text>
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        <text x="180" y="250" font-size="12" font-weight="600" fill="#64748b" text-anchor="middle">4 Unique Combinations</text>
      </g>
    </svg>
  </div>

  <div class="footer">
    <button class="ctrl-btn" id="prevBtn">← Back</button>
    <span class="tag-badge" id="stepCounter">Step 1 of 3</span>
    <button class="ctrl-btn" id="nextBtn">Next →</button>
  </div>

  <script>
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      resetAutoCycle();
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    resetAutoCycle();
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</body>
</html>

Sources of Genetic Variation in Populations

<!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: #f8fafc;
      color: #1e293b;
      padding: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }

    /* Top Controls */
    .controls {
      display: flex;
      gap: 8px;
      margin-bottom: 8px;
      width: 100%;
      max-width: 540px;
      justify-content: center;
    }
    .btn {
      flex: 1;
      padding: 6px 10px;
      font-size: 13px;
      font-weight: 600;
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #475569;
      border-radius: 6px;
      cursor: pointer;
      text-align: center;
      transition: all 0.2s ease;
    }
    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
      box-shadow: 0 1px 4px rgba(2, 132, 199, 0.3);
    }

    /* Main Grid Layout */
    .grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 10px;
      width: 100%;
      max-width: 540px;
    }

    .card-panel {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 10px 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      transition: opacity 0.3s ease, border-color 0.3s ease;
    }
    .card-panel.dim {
      opacity: 0.35;
    }
    .card-panel.highlight {
      border-color: #0284c7;
      box-shadow: 0 0 0 1px #0284c7;
    }

    .panel-title {
      font-size: 13px;
      font-weight: 700;
      color: #334155;
      margin-bottom: 6px;
    }

    .stage-label {
      font-size: 11px;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      color: #64748b;
      margin: 2px 0;
    }

    /* Cell & Metaphase Alignment */
    .cell {
      position: relative;
      width: 110px;
      height: 90px;
      border-radius: 50%;
      border: 2px solid #94a3b8;
      background: #f1f5f9;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 8px;
      margin: 4px 0;
    }

    /* Metaphase plate line */
    .cell::after {
      content: '';
      position: absolute;
      top: 6px;
      bottom: 6px;
      left: 50%;
      width: 1px;
      border-left: 1.5px dashed #cbd5e1;
      transform: translateX(-50%);
    }

    .chrom-pair {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 12px;
      z-index: 1;
    }

    /* Chromosome Visuals */
    .chrom {
      border-radius: 4px;
      position: relative;
    }
    .chrom::after {
      content: '';
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      width: 4px;
      height: 4px;
      border-radius: 50%;
      background: #ffffff;
    }

    .blue { background: #2563eb; }
    .red  { background: #dc2626; }

    .long { width: 9px; height: 30px; }
    .short { width: 9px; height: 18px; }

    .arrow {
      color: #94a3b8;
      font-size: 14px;
      margin: 2px 0;
      line-height: 1;
    }

    /* Gametes container */
    .gametes {
      display: flex;
      gap: 10px;
      margin-top: 2px;
    }
    .gamete {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      border: 1.5px solid #64748b;
      background: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 4px;
    }

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    .formula-bar {
      margin-top: 10px;
      width: 100%;
      max-width: 540px;
      background: #e0f2fe;
      border: 1px solid #bae6fd;
      border-radius: 8px;
      padding: 8px 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
      font-weight: 700;
      color: #0369a1;
      font-size: 14px;
    }
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      border-radius: 4px;
      border: 1px solid #7dd3fc;
      color: #0f172a;
      letter-spacing: 0.5px;
    }
  </style>
</head>
<body>

  
  <div class="controls">
    <button class="btn active" id="btn-all" onclick="showMode('all')">Both Alignments</button>
    <button class="btn" id="btn-p1" onclick="showMode('p1')">Possibility 1</button>
    <button class="btn" id="btn-p2" onclick="showMode('p2')">Possibility 2</button>
  </div>

  
  <div class="grid">
    
    
    <div class="card-panel" id="panel-1">
      <div class="panel-title">Possibility 1</div>
      <div class="stage-label">Metaphase I</div>
      
      <div class="cell">
        
        <div class="chrom-pair">
          <div class="chrom blue long"></div>
          <div class="chrom red long"></div>
        </div>
        
        <div class="chrom-pair">
          <div class="chrom blue short"></div>
          <div class="chrom red short"></div>
        </div>
      </div>

      <div class="arrow">↓</div>
      <div class="stage-label">Gametes</div>

      <div class="gametes">
        <div class="gamete">
          <div class="chrom blue long"></div>
          <div class="chrom blue short"></div>
        </div>
        <div class="gamete">
          <div class="chrom red long"></div>
          <div class="chrom red short"></div>
        </div>
      </div>
    </div>

    
    <div class="card-panel" id="panel-2">
      <div class="panel-title">Possibility 2</div>
      <div class="stage-label">Metaphase I</div>
      
      <div class="cell">
        
        <div class="chrom-pair">
          <div class="chrom blue long"></div>
          <div class="chrom red long"></div>
        </div>
        
        <div class="chrom-pair">
          <div class="chrom red short"></div>
          <div class="chrom blue short"></div>
        </div>
      </div>

      <div class="arrow">↓</div>
      <div class="stage-label">Gametes</div>

      <div class="gametes">
        <div class="gamete">
          <div class="chrom blue long"></div>
          <div class="chrom red short"></div>
        </div>
        <div class="gamete">
          <div class="chrom red long"></div>
          <div class="chrom blue short"></div>
        </div>
      </div>
    </div>

  </div>

  
  <div class="formula-bar">
    <span>Formula:</span>
    <span class="math">2<sup>n</sup> = 2<sup>2</sup> = 4 Unique Gametes</span>
  </div>

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        btnP2.classList.add('active');
        p2.classList.add('highlight');
        p1.classList.add('dim');
      } else {
        btnAll.classList.add('active');
      }
    }
  </script>
</body>
</html>

<!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;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    }

    body {
      background: #ffffff;
      color: #1e293b;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }

    .calculator {
      width: 100%;
      max-width: 580px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    /* Slider / Preset control */
    .controls {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 8px 12px;
      gap: 12px;
    }

    .slider-label {
      font-size: 13px;
      font-weight: 600;
      color: #475569;
      white-space: nowrap;
    }

    .slider-wrap {
      display: flex;
      align-items: center;
      gap: 8px;
      flex: 1;
    }

    input[type="range"] {
      flex: 1;
      accent-color: #2563eb;
      cursor: pointer;
      height: 6px;
    }

    .badge-n {
      font-size: 14px;
      font-weight: 700;
      color: #2563eb;
      min-width: 48px;
      text-align: right;
    }

    /* Multiplication Row */
    .calc-row {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      align-items: center;
      gap: 8px;
    }

    .source-card {
      border-radius: 10px;
      padding: 10px 8px;
      text-align: center;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 3px;
      transition: background 0.2s ease;
    }

    .card-sperm {
      background: #eff6ff;
      border: 1.5px solid #bfdbfe;
    }

    .card-egg {
      background: #fff1f2;
      border: 1.5px solid #fecdd3;
    }

    .card-header {
      font-size: 12px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .card-sperm .card-header { color: #1d4ed8; }
    .card-egg .card-header { color: #be123c; }

    .formula {
      font-size: 13px;
      font-weight: 600;
      color: #64748b;
    }

    .big-num {
      font-size: 18px;
      font-weight: 800;
      line-height: 1.1;
    }

    .card-sperm .big-num { color: #1e40af; }
    .card-egg .big-num { color: #9f1239; }

    .sub-num {
      font-size: 11px;
      color: #64748b;
      font-weight: 500;
    }

    .op-symbol {
      font-size: 22px;
      font-weight: 800;
      color: #94a3b8;
    }

    /* Result Card */
    .result-card {
      background: #faf5ff;
      border: 1.5px solid #ddd6fe;
      border-radius: 10px;
      padding: 12px 10px;
      text-align: center;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
    }

    .result-label {
      font-size: 12px;
      font-weight: 700;
      color: #6b21a8;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .result-total {
      font-size: 24px;
      font-weight: 800;
      color: #581c87;
      line-height: 1.1;
    }

    .result-approx {
      font-size: 13px;
      font-weight: 600;
      color: #7e22ce;
    }

    /* Footer Callout */
    .infinite-banner {
      background: #fefce8;
      border: 1px solid #fef08a;
      border-radius: 8px;
      padding: 8px 12px;
      text-align: center;
      font-size: 12px;
      font-weight: 700;
      color: #854d0e;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
    }

    .star {
      color: #eab308;
      font-size: 14px;
    }

    @media (max-width: 400px) {
      .big-num { font-size: 16px; }
      .result-total { font-size: 20px; }
      .controls { padding: 6px 8px; }
      .slider-label { font-size: 12px; }
    }
  </style>
</head>
<body>
  <div class="calculator">
    
    <div class="controls">
      <span class="slider-label">Chromosome Pairs (n)</span>
      <div class="slider-wrap">
        <input type="range" id="pairSlider" min="1" max="23" value="23" aria-label="Chromosome Pairs">
        <span class="badge-n" id="nVal">n = 23</span>
      </div>
    </div>

    
    <div class="calc-row">
      <div class="source-card card-sperm">
        <div class="card-header">♂ Sperm</div>
        <div class="formula">2<sup id="spermExp">23</sup></div>
        <div class="big-num" id="spermCount">8,388,608</div>
        <div class="sub-num" id="spermApprox">~8.4 Million</div>
      </div>

      <div class="op-symbol">×</div>

      <div class="source-card card-egg">
        <div class="card-header">♀ Egg</div>
        <div class="formula">2<sup id="eggExp">23</sup></div>
        <div class="big-num" id="eggCount">8,388,608</div>
        <div class="sub-num" id="eggApprox">~8.4 Million</div>
      </div>
    </div>

    
    <div class="result-card">
      <div class="result-label">Random Fertilization (Zygote)</div>
      <div class="result-total" id="zygoteTotal">> 70,000,000,000,000</div>
      <div class="result-approx" id="zygoteApprox">Over 70 Trillion Combinations</div>
    </div>

    
    <div class="infinite-banner">
      <span class="star">✦</span>
      <span>+ Crossing Over &amp; Mutation = Virtually Infinite Diversity</span>
    </div>
  </div>

  <script>
    const slider = document.getElementById('pairSlider');
    const nVal = document.getElementById('nVal');
    const spermExp = document.getElementById('spermExp');
    const eggExp = document.getElementById('eggExp');
    const spermCount = document.getElementById('spermCount');
    const eggCount = document.getElementById('eggCount');
    const spermApprox = document.getElementById('spermApprox');
    const eggApprox = document.getElementById('eggApprox');
    const zygoteTotal = document.getElementById('zygoteTotal');
    const zygoteApprox = document.getElementById('zygoteApprox');

    function formatNumber(n) {
      if (n >= 1e12) return (n / 1e12).toFixed(1) + ' Trillion';
      if (n >= 1e9) return (n / 1e9).toFixed(1) + ' Billion';
      if (n >= 1e6) return (n / 1e6).toFixed(1) + ' Million';
      if (n >= 1e3) return (n / 1e3).toFixed(1) + ' Thousand';
      return n.toLocaleString();
    }

    function update() {
      const n = parseInt(slider.value, 10);
      nVal.textContent = (n === 23) ? 'n = 23 (Human)' : `n = ${n}`;
      spermExp.textContent = n;
      eggExp.textContent = n;

      const single = BigInt(2) ** BigInt(n);
      const total = single * single;

      const singleNum = Number(single);
      const totalNum = Number(total);

      spermCount.textContent = single.toLocaleString();
      eggCount.textContent = single.toLocaleString();

      if (n === 23) {
        spermApprox.textContent = '~8.4 Million';
        eggApprox.textContent = '~8.4 Million';
        zygoteTotal.textContent = '> 70,000,000,000,000';
        zygoteApprox.textContent = 'Over 70 Trillion Combinations';
      } else {
        spermApprox.textContent = singleNum >= 1000 ? `~${formatNumber(singleNum)}` : 'Combinations';
        eggApprox.textContent = singleNum >= 1000 ? `~${formatNumber(singleNum)}` : 'Combinations';
        zygoteTotal.textContent = total.toLocaleString();
        zygoteApprox.textContent = `${formatNumber(totalNum)} Combinations`;
      }
    }

    slider.addEventListener('input', update);
    update();
  </script>
</body>
</html>

<!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;
      color: #1e2945;
      background: #f8fafc;
      width: 100%;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }

    .header-bar {
      display: flex;
      gap: 6px;
      margin-bottom: 8px;
      width: 100%;
      max-width: 480px;
    }

    .tab-btn {
      flex: 1;
      padding: 6px 4px;
      font-size: 13px;
      font-weight: 600;
      text-align: center;
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #64748b;
      border-radius: 6px;
      cursor: pointer;
      user-select: none;
      transition: all 0.25s ease;
    }

    .tab-btn.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #2563eb;
      box-shadow: 0 2px 4px rgba(37, 99, 235, 0.2);
    }

    .diagram-area {
      display: flex;
      flex-direction: column;
      width: 100%;
      max-width: 480px;
      gap: 10px;
      background: #ffffff;
      border-radius: 12px;
      padding: 12px;
      box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    }

    /* DNA Mutation Banner */
    .mutation-source {
      background: #f0f4f8;
      border: 1.5px solid #cbd5e1;
      border-radius: 8px;
      padding: 8px 12px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      transition: opacity 0.3s ease;
    }

    .dna-visual {
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .helix-icon {
      font-size: 24px;
      line-height: 1;
    }

    .base-pair {
      font-family: ui-monospace, monospace;
      font-weight: 700;
      font-size: 14px;
      padding: 3px 6px;
      border-radius: 4px;
      background: #e2e8f0;
      color: #475569;
    }

    .base-mutated {
      background: #fef08a;
      color: #854d0e;
      border: 1px dashed #ca8a04;
      animation: pulse-glow 2s infinite ease-in-out;
    }

    @keyframes pulse-glow {
      0%, 100% { transform: scale(1); }
      50% { transform: scale(1.06); }
    }

    .badge-label {
      font-size: 13px;
      font-weight: 700;
      color: #1e2945;
      text-align: right;
    }

    .badge-sub {
      font-size: 11px;
      font-weight: 500;
      color: #64748b;
    }

    /* Branches Container */
    .branches {
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .branch-card {
      display: grid;
      grid-template-columns: auto 1fr auto;
      align-items: center;
      gap: 10px;
      padding: 10px 12px;
      border-radius: 8px;
      border: 1.5px solid #e2e8f0;
      background: #f8fafc;
      transition: all 0.3s ease;
      cursor: pointer;
    }

    .branch-card.somatic {
      border-left: 4px solid #94a3b8;
    }

    .branch-card.germline {
      border-left: 4px solid #10b981;
    }

    .branch-card.active-somatic {
      background: #f8fafc;
      border-color: #64748b;
      box-shadow: 0 0 0 2px #cbd5e1;
    }

    .branch-card.active-germline {
      background: #f0fdf4;
      border-color: #10b981;
      box-shadow: 0 0 0 2px #a7f3d0;
    }

    .branch-card.dimmed {
      opacity: 0.35;
    }

    .branch-icon {
      font-size: 22px;
      width: 32px;
      text-align: center;
    }

    .branch-info {
      display: flex;
      flex-direction: column;
    }

    .branch-title {
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
    }

    .branch-desc {
      font-size: 12px;
      color: #64748b;
      font-weight: 500;
    }

    .fate-pill {
      font-size: 12px;
      font-weight: 700;
      padding: 4px 8px;
      border-radius: 999px;
      display: flex;
      align-items: center;
      gap: 4px;
      white-space: nowrap;
    }

    .fate-no {
      background: #f1f5f9;
      color: #64748b;
      border: 1px solid #cbd5e1;
    }

    .fate-yes {
      background: #dcfce7;
      color: #15803d;
      border: 1px solid #86efac;
    }

    /* Responsive for small screens */
    @media (max-width: 380px) {
      .badge-label { font-size: 12px; }
      .branch-title { font-size: 13px; }
      .branch-desc { font-size: 11px; }
      .fate-pill { font-size: 11px; padding: 3px 6px; }
    }
  </style>
</head>
<body>

  
  <div class="header-bar">
    <button class="tab-btn active" id="btn-all" onclick="setMode('all')">Compare Both</button>
    <button class="tab-btn" id="btn-somatic" onclick="setMode('somatic')">Somatic</button>
    <button class="tab-btn" id="btn-germline" onclick="setMode('germline')">Germline</button>
  </div>

  
  <div class="diagram-area">
    
    
    <div class="mutation-source">
      <div class="dna-visual">
        <span class="helix-icon">🧬</span>
        <div>
          <span class="base-pair">A-T</span>
          <span style="font-size: 12px; color: #94a3b8;">➔</span>
          <span class="base-pair base-mutated">G-C</span>
        </div>
      </div>
      <div>
        <div class="badge-label">Point Mutation</div>
        <div class="badge-sub">New Allele Created</div>
      </div>
    </div>

    
    <div class="branches">
      
      
      <div class="branch-card somatic" id="card-somatic" onclick="setMode('somatic')">
        <div class="branch-icon">👤</div>
        <div class="branch-info">
          <div class="branch-title">Somatic Cell</div>
          <div class="branch-desc">Body tissue only</div>
        </div>
        <div class="fate-pill fate-no">
          <span>✕</span> Not Inherited
        </div>
      </div>

      
      <div class="branch-card germline" id="card-germline" onclick="setMode('germline')">
        <div class="branch-icon">🌱</div>
        <div class="branch-info">
          <div class="branch-title">Germline Cell</div>
          <div class="branch-desc">Egg / Sperm gamete</div>
        </div>
        <div class="fate-pill fate-yes">
          <span>✓</span> Passed On
        </div>
      </div>

    </div>

  </div>

  <script>
    function setMode(mode) {
      const btnAll = document.getElementById('btn-all');
      const btnSomatic = document.getElementById('btn-somatic');
      const btnGermline = document.getElementById('btn-germline');
      const cardSomatic = document.getElementById('card-somatic');
      const cardGermline = document.getElementById('card-germline');

      // Reset active button classes
      btnAll.classList.remove('active');
      btnSomatic.classList.remove('active');
      btnGermline.classList.remove('active');

      // Reset card states
      cardSomatic.className = 'branch-card somatic';
      cardGermline.className = 'branch-card germline';

      if (mode === 'somatic') {
        btnSomatic.classList.add('active');
        cardSomatic.classList.add('active-somatic');
        cardGermline.classList.add('dimmed');
      } else if (mode === 'germline') {
        btnGermline.classList.add('active');
        cardGermline.classList.add('active-germline');
        cardSomatic.classList.add('dimmed');
      } else {
        btnAll.classList.add('active');
      }
    }
  </script>
</body>
</html>

Point Mutations: Silent, Missense, and Nonsense Mutations

OGS.11.LS.EV.3

Aligned learning resources

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