<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Thermoregulation Feedback Loop</title>
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #0f172a;
      background: #ffffff;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
      padding: 12px 8px;
      overflow-x: hidden;
    }

    /* Controls Header */
    .controls {
      display: flex;
      gap: 8px;
      margin-bottom: 8px;
      flex-wrap: wrap;
      justify-content: center;
      width: 100%;
      max-width: 580px;
      z-index: 10;
    }
    .mode-btn {
      background: #f8fafc;
      border: 1.5px solid #cbd5e1;
      padding: 7px 14px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      color: #334155;
      transition: background-color 0.3s ease, border-color 0.3s ease, color 0.3s ease, box-shadow 0.3s ease;
      user-select: none;
      display: inline-flex;
      align-items: center;
      gap: 5px;
    }
    .mode-btn:focus-visible {
      outline: 2px solid #0284c7;
      outline-offset: 2px;
    }
    .mode-btn.active-heat {
      background: #fff1f2;
      border-color: #f43f5e;
      color: #9f1239;
      box-shadow: 0 1px 3px rgba(244, 63, 94, 0.2);
    }
    .mode-btn.active-cold {
      background: #f0f9ff;
      border-color: #0284c7;
      color: #0369a1;
      box-shadow: 0 1px 3px rgba(2, 132, 199, 0.2);
    }
    .mode-btn.active-norm {
      background: #ecfdf5;
      border-color: #10b981;
      color: #065f46;
      box-shadow: 0 1px 3px rgba(16, 185, 129, 0.2);
    }

    /* Main SVG Canvas Container */
    .diagram-area {
      width: 100%;
      max-width: 600px;
      display: flex;
      justify-content: center;
      align-items: center;
    }
    svg {
      width: 100%;
      height: auto;
      display: block;
    }

    /* SVG typography */
    .node-title {
      font-size: 13px;
      font-weight: 700;
    }
    .node-sub {
      font-size: 11px;
      font-weight: 500;
      fill: #334155;
    }
    .temp-readout {
      font-size: 22px;
      font-weight: 800;
      transition: fill 0.4s ease;
    }
    .setpoint-label {
      font-size: 10.5px;
      font-weight: 800;
      letter-spacing: 0.6px;
      fill: #047857;
    }

    /* High contrast dynamic highlighting */
    .branch-heat, .branch-cold {
      transition: opacity 0.4s ease, filter 0.4s ease;
    }
    /* Maintained readable opacity for inactive branches (>=4.5:1 contrast) */
    .dimmed {
      opacity: 0.62;
    }
    .active-branch {
      opacity: 1;
    }

    /* Smooth scale beam balance transitions */
    #beam-group {
      transition: transform 0.55s cubic-bezier(0.34, 1.3, 0.64, 1);
      transform-origin: 285px 185px;
    }

    /* Feedback Flow Pulses - Calm, non-strobing animation */
    .flow-arrow {
      stroke-dasharray: 6, 6;
      animation: dash 2.4s linear infinite;
    }
    @keyframes dash {
      to {
        stroke-dashoffset: -24;
      }
    }

    /* Gentle, safe animations (>300ms) */
    .shiver-elem {
      animation: shiver 0.45s ease-in-out infinite alternate;
      transform-origin: 512px 322px;
    }
    @keyframes shiver {
      0% { transform: translate(0, 0); }
      50% { transform: translate(-1.5px, 0.5px); }
      100% { transform: translate(1.5px, -0.5px); }
    }
    .sweat-drop {
      animation: drop 1.6s cubic-bezier(0.4, 0, 0.2, 1) infinite;
    }
    @keyframes drop {
      0% { opacity: 0; transform: translateY(-2px); }
      40% { opacity: 0.9; }
      80% { opacity: 0.8; transform: translateY(7px); }
      100% { opacity: 0; transform: translateY(9px); }
    }

    @media (max-width: 420px) {
      .controls {
        gap: 5px;
      }
      .mode-btn {
        padding: 5px 10px;
        font-size: 11.5px;
      }
    }
  </style>
</head>
<body>

  
  <div class="controls" role="group" aria-label="Thermoregulation simulation controls">
    <button class="mode-btn" id="btnHeat" onclick="setMode('heat')">☀️ Heat Stress</button>
    <button class="mode-btn active-norm" id="btnNorm" onclick="setMode('norm')">⚖️ Equilibrium (37°C)</button>
    <button class="mode-btn" id="btnCold" onclick="setMode('cold')">❄️ Cold Stress</button>
  </div>

  
  <div class="diagram-area">
    <svg viewBox="0 0 570 370" role="img" aria-label="Thermoregulation feedback loop diagram">
      <defs>
        
        <linearGradient id="coralGrad" x1="0" y1="0" x2="1" y2="1">
          <stop offset="0%" stop-color="#fff5f5"/>
          <stop offset="100%" stop-color="#fee2e2"/>
        </linearGradient>
        <linearGradient id="blueGrad" x1="0" y1="0" x2="1" y2="1">
          <stop offset="0%" stop-color="#f0f9ff"/>
          <stop offset="100%" stop-color="#e0f2fe"/>
        </linearGradient>
        <linearGradient id="centerGrad" x1="0" y1="0" x2="1" y2="1">
          <stop offset="0%" stop-color="#ffffff"/>
          <stop offset="100%" stop-color="#f8fafc"/>
        </linearGradient>

        
        <filter id="shadow" x="-5%" y="-8%" width="110%" height="120%">
          <feDropShadow dx="0" dy="2" stdDeviation="2" flood-color="#0f172a" flood-opacity="0.08"/>
        </filter>

        
        <marker id="arrow-coral" viewBox="0 0 10 10" refX="7" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
          <path d="M 0 1.5 L 9 5 L 0 8.5 z" fill="#e11d48"/>
        </marker>
        <marker id="arrow-blue" viewBox="0 0 10 10" refX="7" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
          <path d="M 0 1.5 L 9 5 L 0 8.5 z" fill="#0284c7"/>
        </marker>
      </defs>

      
      <g id="branch-heat" class="branch-heat">
        
        <path d="M 235 145 C 180 120 135 95 105 70" fill="none" stroke="#f43f5e" stroke-width="2.5" stroke-dasharray="5,4" marker-end="url(#arrow-coral)"/>
        <path d="M 185 42 L 365 42" fill="none" stroke="#fb7185" stroke-width="2" marker-end="url(#arrow-coral)"/>
        <path d="M 465 72 C 485 110 420 140 335 160" fill="none" stroke="#e11d48" stroke-width="2.5" class="flow-arrow" marker-end="url(#arrow-coral)"/>

        
        <g transform="translate(20, 18)">
          <rect width="165" height="48" rx="8" fill="url(#coralGrad)" stroke="#fda4af" stroke-width="1.5" filter="url(#shadow)"/>
          <text x="12" y="21" class="node-title" fill="#9f1239">▲ Temp Rises</text>
          <text x="12" y="37" class="node-sub">Hypothalamus alerts</text>
          <circle cx="145" cy="24" r="12" fill="#ffe4e6" stroke="#fecdd3" stroke-width="1"/>
          <text x="145" y="28" text-anchor="middle" font-size="13">🌡️</text>
        </g>

        
        <g transform="translate(370, 14)">
          <rect width="180" height="56" rx="8" fill="url(#coralGrad)" stroke="#f43f5e" stroke-width="1.5" filter="url(#shadow)"/>
          <text x="12" y="19" class="node-title" fill="#9f1239">Cooling Responses</text>
          <text x="12" y="34" class="node-sub">• Vasodilation (flush)</text>
          <text x="12" y="47" class="node-sub">• Sweat evaporation</text>
          <circle cx="158" cy="28" r="13" fill="#ffffff" stroke="#fecdd3" stroke-width="1"/>
          <text x="158" y="29" text-anchor="middle" font-size="12">💦</text>
          <path class="sweat-drop" d="M 158 38 C 158 38 156 41 156 43 A 2 2 0 0 0 160 43 C 160 41 158 38 158 38 Z" fill="#0284c7"/>
        </g>

        
        <rect x="390" y="100" width="160" height="22" rx="11" fill="#fff1f2" stroke="#fecdd3" stroke-width="1.2"/>
        <text x="470" y="115" text-anchor="middle" font-size="10.5" font-weight="800" fill="#be123c">− NEGATIVE FEEDBACK</text>
      </g>


      
      <g id="branch-cold" class="branch-cold">
        
        <path d="M 235 225 C 180 250 135 275 105 300" fill="none" stroke="#0284c7" stroke-width="2.5" stroke-dasharray="5,4" marker-end="url(#arrow-blue)"/>
        <path d="M 185 328 L 365 328" fill="none" stroke="#38bdf8" stroke-width="2" marker-end="url(#arrow-blue)"/>
        <path d="M 465 298 C 485 260 420 230 335 210" fill="none" stroke="#0284c7" stroke-width="2.5" class="flow-arrow" marker-end="url(#arrow-blue)"/>

        
        <g transform="translate(20, 304)">
          <rect width="165" height="48" rx="8" fill="url(#blueGrad)" stroke="#7dd3fc" stroke-width="1.5" filter="url(#shadow)"/>
          <text x="12" y="21" class="node-title" fill="#0369a1">▼ Temp Drops</text>
          <text x="12" y="37" class="node-sub">Hypothalamus alerts</text>
          <circle cx="145" cy="24" r="12" fill="#e0f2fe" stroke="#bae6fd" stroke-width="1"/>
          <text x="145" y="28" text-anchor="middle" font-size="13">❄️</text>
        </g>

        
        <g transform="translate(370, 300)">
          <rect width="180" height="56" rx="8" fill="url(#blueGrad)" stroke="#0284c7" stroke-width="1.5" filter="url(#shadow)"/>
          <text x="12" y="19" class="node-title" fill="#0369a1">Warming Responses</text>
          <text x="12" y="34" class="node-sub">• Vasoconstriction</text>
          <text x="12" y="47" class="node-sub">• Muscle shivering</text>
          <circle cx="158" cy="28" r="13" fill="#ffffff" stroke="#bae6fd" stroke-width="1"/>
          <g class="shiver-elem">
            <text x="158" y="33" text-anchor="middle" font-size="13">⚡</text>
          </g>
        </g>

        
        <rect x="390" y="248" width="160" height="22" rx="11" fill="#f0f9ff" stroke="#bae6fd" stroke-width="1.2"/>
        <text x="470" y="263" text-anchor="middle" font-size="10.5" font-weight="800" fill="#0369a1">− NEGATIVE FEEDBACK</text>
      </g>


      
      
      <polygon points="285,185 270,220 300,220" fill="#475569"/>
      <rect x="258" y="220" width="54" height="6" rx="3" fill="#334155"/>

      
      <g id="beam-group">
        
        <line x1="185" y1="185" x2="385" y2="185" stroke="#334155" stroke-width="4.5" stroke-linecap="round"/>
        
        
        <line x1="195" y1="185" x2="195" y2="200" stroke="#64748b" stroke-width="1.5"/>
        <ellipse cx="195" cy="200" rx="18" ry="4.5" fill="#cbd5e1" stroke="#94a3b8" stroke-width="1"/>
        <text x="195" y="178" text-anchor="middle" font-size="11" font-weight="800" fill="#e11d48">HOT</text>

        
        <line x1="375" y1="185" x2="375" y2="200" stroke="#64748b" stroke-width="1.5"/>
        <ellipse cx="375" cy="200" rx="18" ry="4.5" fill="#cbd5e1" stroke="#94a3b8" stroke-width="1"/>
        <text x="375" y="178" text-anchor="middle" font-size="11" font-weight="800" fill="#0284c7">COLD</text>

        
        <rect x="225" y="146" width="120" height="72" rx="10" fill="url(#centerGrad)" stroke="#10b981" stroke-width="2" filter="url(#shadow)"/>
        
        
        <text x="285" y="165" text-anchor="middle" class="setpoint-label">SET POINT</text>
        <text id="tempText" x="285" y="191" text-anchor="middle" class="temp-readout" fill="#047857">37.0°C</text>
        <text id="subText" x="285" y="207" text-anchor="middle" font-size="10.5" font-weight="600" fill="#475569">98.6°F • Equilibrium</text>
      </g>

      
      <circle cx="285" cy="185" r="4.5" fill="#10b981" stroke="#ffffff" stroke-width="1.5"/>
    </svg>
  </div>

  <script>
    const beam = document.getElementById('beam-group');
    const tempText = document.getElementById('tempText');
    const subText = document.getElementById('subText');
    const branchHeat = document.getElementById('branch-heat');
    const branchCold = document.getElementById('branch-cold');

    const btnHeat = document.getElementById('btnHeat');
    const btnNorm = document.getElementById('btnNorm');
    const btnCold = document.getElementById('btnCold');

    let autoTimer = null;
    let currentStep = 0;

    function setMode(mode) {
      btnHeat.className = 'mode-btn';
      btnNorm.className = 'mode-btn';
      btnCold.className = 'mode-btn';

      if (mode === 'heat') {
        btnHeat.classList.add('active-heat');
        beam.style.transform = 'rotate(-8deg)';
        tempText.textContent = '39.2°C';
        tempText.setAttribute('fill', '#be123c');
        subText.textContent = 'High • Cooling Active';
        branchHeat.className.baseVal = 'branch-heat active-branch';
        branchCold.className.baseVal = 'branch-cold dimmed';
      } else if (mode === 'cold') {
        btnCold.classList.add('active-cold');
        beam.style.transform = 'rotate(8deg)';
        tempText.textContent = '35.4°C';
        tempText.setAttribute('fill', '#0369a1');
        subText.textContent = 'Low • Warming Active';
        branchCold.className.baseVal = 'branch-cold active-branch';
        branchHeat.className.baseVal = 'branch-heat dimmed';
      } else {
        btnNorm.classList.add('active-norm');
        beam.style.transform = 'rotate(0deg)';
        tempText.textContent = '37.0°C';
        tempText.setAttribute('fill', '#047857');
        subText.textContent = '98.6°F • Equilibrium';
        branchHeat.className.baseVal = 'branch-heat';
        branchCold.className.baseVal = 'branch-cold';
      }
    }

    // Auto-cycle through equilibrium and stress loops gently
    const sequence = ['norm', 'heat', 'norm', 'cold'];
    function startAutoLoop() {
      autoTimer = setInterval(() => {
        currentStep = (currentStep + 1) % sequence.length;
        setMode(sequence[currentStep]);
      }, 4000);
    }

    // Stop auto-loop on manual user selection
    [btnHeat, btnNorm, btnCold].forEach(btn => {
      btn.addEventListener('click', () => {
        if (autoTimer) {
          clearInterval(autoTimer);
          autoTimer = null;
        }
      });
    });

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

Homeostatic Control Loops and Negative Feedback Principles

<!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 {
      width: 100%;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: #ffffff;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      user-select: none;
    }
    .header-row {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 8px;
    }
    .title-badge {
      font-size: 13px;
      font-weight: 700;
      letter-spacing: 0.5px;
      text-transform: uppercase;
      color: #475569;
    }
    .controls {
      display: flex;
      gap: 6px;
    }
    .btn-ctrl {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      padding: 4px 10px;
      font-size: 13px;
      font-weight: 600;
      color: #334155;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      transition: background 0.2s, box-shadow 0.2s;
    }
    .btn-ctrl:hover {
      background: #e2e8f0;
    }
    .btn-ctrl.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #2563eb;
    }
    .grid-panels {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
      width: 100%;
    }
    @media (max-width: 480px) {
      .grid-panels {
        grid-template-columns: 1fr;
      }
    }
    .panel-card {
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 10px;
      display: flex;
      flex-direction: column;
      gap: 6px;
      position: relative;
    }
    .panel-header {
      display: flex;
      justify-content: space-between;
      align-items: baseline;
    }
    .panel-title {
      font-size: 14px;
      font-weight: 700;
      color: #0f172a;
    }
    .panel-tag {
      font-size: 11px;
      font-weight: 600;
      padding: 2px 6px;
      border-radius: 4px;
    }
    .tag-neg {
      background: #e0f2fe;
      color: #0369a1;
    }
    .tag-pos {
      background: #fef3c7;
      color: #b45309;
    }
    .svg-container {
      width: 100%;
      height: 180px;
      position: relative;
    }
    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }
    .axis {
      stroke: #94a3b8;
      stroke-width: 1.5;
      stroke-linecap: round;
    }
    .grid-line {
      stroke: #cbd5e1;
      stroke-dasharray: 4 4;
      stroke-width: 1.5;
    }
    .curve-neg {
      fill: none;
      stroke: #0284c7;
      stroke-width: 3;
      stroke-linecap: round;
      stroke-linejoin: round;
    }
    .curve-pos {
      fill: none;
      stroke: #ea580c;
      stroke-width: 3;
      stroke-linecap: round;
      stroke-linejoin: round;
    }
    .event-line {
      stroke: #dc2626;
      stroke-dasharray: 3 3;
      stroke-width: 1.5;
    }
    .lbl {
      font-size: 11px;
      fill: #64748b;
      font-weight: 600;
    }
    .lbl-accent-neg {
      font-size: 11px;
      fill: #0369a1;
      font-weight: 700;
    }
    .lbl-accent-pos {
      font-size: 11px;
      fill: #c2410c;
      font-weight: 700;
    }
    .lbl-event {
      font-size: 11px;
      fill: #dc2626;
      font-weight: 700;
    }
    .tracer {
      stroke: #ffffff;
      stroke-width: 2;
      filter: drop-shadow(0 1px 3px rgba(0,0,0,0.3));
    }
    .phase-badge {
      position: absolute;
      bottom: 8px;
      left: 10px;
      right: 10px;
      background: rgba(255, 255, 255, 0.95);
      border: 1px solid #e2e8f0;
      border-radius: 6px;
      padding: 4px 8px;
      font-size: 12px;
      font-weight: 600;
      display: flex;
      align-items: center;
      justify-content: space-between;
      box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    }
  </style>
</head>
<body>

  <div class="header-row">
    <div class="title-badge">Feedback Response Curves</div>
    <div class="controls">
      <button class="btn-ctrl active" id="playBtn">▶ Play</button>
      <button class="btn-ctrl" id="resetBtn">↺ Reset</button>
    </div>
  </div>

  <div class="grid-panels">
    
    <div class="panel-card" id="negPanel">
      <div class="panel-header">
        <span class="panel-title">Negative Feedback</span>
        <span class="panel-tag tag-neg">Stabilizing</span>
      </div>
      <div class="svg-container">
        <svg viewBox="0 0 300 180" id="svgNeg">
          
          <line x1="30" y1="155" x2="285" y2="155" class="axis" />
          <line x1="30" y1="155" x2="30" y2="20" class="axis" />
          <text x="285" y="170" text-anchor="end" class="lbl">Time →</text>
          <text x="25" y="16" class="lbl">Level</text>

          
          <line x1="30" y1="90" x2="280" y2="90" class="grid-line" />
          <text x="35" y="82" class="lbl-accent-neg">Set Point</text>

          
          <path id="pathNeg" class="curve-neg" d="" />

          
          <circle id="dotNeg" class="tracer" r="6" fill="#0284c7" cx="30" cy="90" />
        </svg>
      </div>
      <div class="phase-badge">
        <span id="textNegStatus" style="color:#0369a1;">Disturbance Detected</span>
        <span style="font-size:11px; color:#64748b;">Oscillates → Settles</span>
      </div>
    </div>

    
    <div class="panel-card" id="posPanel">
      <div class="panel-header">
        <span class="panel-title">Positive Feedback</span>
        <span class="panel-tag tag-pos">Amplifying</span>
      </div>
      <div class="svg-container">
        <svg viewBox="0 0 300 180" id="svgPos">
          
          <line x1="30" y1="155" x2="285" y2="155" class="axis" />
          <line x1="30" y1="155" x2="30" y2="20" class="axis" />
          <text x="285" y="170" text-anchor="end" class="lbl">Time →</text>
          <text x="25" y="16" class="lbl">Level</text>

          
          <line x1="30" y1="140" x2="280" y2="140" class="grid-line" />
          <text x="35" y="134" class="lbl">Baseline</text>

          
          <line x1="210" y1="20" x2="210" y2="155" class="event-line" />
          <text x="208" y="32" text-anchor="end" class="lbl-event">Terminating Event</text>

          
          <path id="pathPos" class="curve-pos" d="" />

          
          <circle id="dotPos" class="tracer" r="6" fill="#ea580c" cx="30" cy="140" />
        </svg>
      </div>
      <div class="phase-badge">
        <span id="textPosStatus" style="color:#c2410c;">Initial Stimulus</span>
        <span style="font-size:11px; color:#64748b;">Surge → Abrupt Reset</span>
      </div>
    </div>
  </div>

  <script>
    // Exact Mathematical Path Generation
    const W = 250; // effective width x: 30 to 280
    const x0 = 30;

    // 1. Negative Feedback: Damped sine wave converging to Set Point (y = 90)
    // y(t) = 90 - A * exp(-lambda * t) * cos(omega * t)
    function calcNeg(normT) {
      // normT: 0 to 1
      const x = x0 + normT * W;
      const decay = Math.exp(-3.6 * normT);
      const osc = Math.cos(normT * Math.PI * 4.5);
      const amp = 58;
      const y = 90 - amp * decay * osc;
      return { x, y };
    }

    let dNeg = '';
    const steps = 120;
    for (let i = 0; i <= steps; i++) {
      const pt = calcNeg(i / steps);
      dNeg += (i === 0 ? `M ${pt.x.toFixed(1)} ${pt.y.toFixed(1)}` : ` L ${pt.x.toFixed(1)} ${pt.y.toFixed(1)}`);
    }
    document.getElementById('pathNeg').setAttribute('d', dNeg);

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    <button class="btn-step" onclick="setStep(3)">4. Effector</button>
    <button class="btn-step" onclick="setStep(4)">5. Response</button>
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      <span class="center-text">37°C<br>Set Point</span>
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    <span><strong>1. Stimulus:</strong> Body temperature rises above the 37°C homeostatic set point.</span>
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Principles of Homeostasis and the Internal Environment

Dynamic Equilibrium and Set Point Fluctuations

Negative Feedback Systems in Physiological Regulation

Positive Feedback Loops and Amplification Cascades

Thermoregulation Mechanisms in Endothermic Mammals

Ectothermic Temperature Regulation and Behavioural Control

Temperature Receptors and Hypothalamic Coordination

Physiological Effectors: Vasodilation, Vasoconstriction, and Sweating

science

Principles of Homeostasis and Dynamic Equilibrium

Pancreatic Islets of Langerhans: Alpha and Beta Cells

Insulin Secretion and Glucose Uptake Mechanisms

Glucagon Action: Glycogenolysis and Gluconeogenesis

Adrenaline and the Second Messenger cAMP Pathway

Comparing Glycogenesis, Glycogenolysis, and Gluconeogenesis

Etiology and Pathology of Type 1 Diabetes Mellitus

Risk Factors and Management of Type 2 Diabetes Mellitus

Colorimetric Testing and Blood Glucose Monitoring

Blood Glucose Regulation and Endocrine Control

Gross and Microscopic Structure of the Mammalian Kidney

The Nephron and Ultrafiltration in Bowman's Capsule

Selective Reabsorption in the Proximal Convoluted Tubule

Hairpin Countercurrent Multiplier in the Loop of Henle

Distal Convoluted Tubule and Mineral Ion Reabsorption

Osmoreceptors in the Hypothalamus and ADH Release

Cellular Mechanism of ADH Action via Aquaporins

Pathology of Renal Failure and Kidney Dialysis Principles

Osmoregulation and Renal Excretion

Sensory Receptors as Biological Transducers

Pacinian Corpuscles and Generator Potentials

Stretch-Mediated Sodium Channels in Mechanoreceptors

Plant and Animal Taxes and Kineses

Investigating Woodlouse Behaviour Using Choice Chambers

Reflex Arcs and Rapid Involuntary Protective Responses

Stimuli Detection and Sensory Receptors

Retinal Photoreceptors: Rod Cells and Rhodopsin Bleaching

Cone Cells: Iodopsin and Trichromatic Colour Vision

Visual Acuity versus Visual Sensitivity and Retinal Convergence

Myogenic Stimulation of the Heart and the Cardiac Conduction System

Autonomic Nervous Control of Heart Rate: Sympathetic and Parasympathetic

Chemoreceptor and Baroreceptor Reflexes in Heart Rate Regulation

Photoreceptors and Autonomic Heart Rate Control

Thermoregulation and Metabolic Rate Control in Endotherms

Osmoregulation and Mammalian Nephron Countercurrent Multiplication

Resting Membrane Potential and the Action Potential Waveform

Saltatory Conduction and Nerve Impulse Propagation Velocity

Unidirectional Impulse Transmission Across Synapses

Synaptic Integration: Spatial and Temporal Summation

Sensory Receptors and Signal Transduction Mechanisms

Endocrine Signaling and Blood Glucose Homeostasis

Hormone Action: Steroid Nuclear Receptors vs Peptide Second Messengers

Animal Physiology: Homeostasis and Signaling

Plant Growth Factors and Indole-3-Acetic Acid (IAA)

Phototropism in Shoots and Unilateral Light Response

Gravitropism in Roots and Shoots: Statolith Mechanisms

Auxin Efflux Carriers and the Acid Growth Hypothesis

Gibberellins and Seed Germination Pathways

Abscisic Acid and Stomatal Closure During Water Stress

Plant Responses and Hormonal Coordination

Resting Membrane Potential and the Sodium-Potassium Pump

Depolarisation and Voltage-Gated Sodium Channel Kinetics

Repolarisation, Hyperpolarisation, and Potassium Leak Channels

The All-or-Nothing Principle and Threshold Potential

Refractory Periods: Absolute and Relative Conduction Limits

Factors Affecting Nerve Impulse Conduction Velocity

Myelination, Schwann Cells, and Saltatory Conduction

Measuring Action Potentials Using Oscilloscope Traces

Nerve Impulses and Action Potential Conduction

Structure of a Cholinergic Synapse and Vesicular Storage

Voltage-Gated Calcium Influx and Acetylcholine Exocytosis

Acetylcholine Receptor Binding and Post-Synaptic Depolarisation

Acetylcholinesterase Hydrolysis and Synaptic Recycling

Unidirectional Transmission Across Chemical Synapses

Spatial and Temporal Summation Mechanisms

Inhibitory Synapses: GABA and Hyperpolarisation

Neuromuscular Junctions versus Cholinergic Synapses

Pharmacological Agents and Neurotoxin Effects on Synapses

Synaptic Transmission and Intercellular Signalling

Sistemas energéticos musculares: fosfágenos, glucólisis y fosforilación

Estructura y fisiología de la contracción muscular

Tipos de fibras musculares: lentas versus rápidas

Adaptaciones cardiovasculares al entrenamiento físico

Fisiología respiratoria y consumo máximo de oxígeno (VO2 máx)

Termorregulación, sudoración e hidratación en el deporte

Nutrición deportiva: macronutrientes y recuperación de glucógeno

Fisiología del ejercicio y nutrición deportiva

Gross and Ultrastructural Anatomy of Skeletal Muscle

The Sarcomere Structure: Z-Lines, Actin, and Myosin Filaments

The Sliding Filament Theory of Muscle Contraction

Calcium Ions, Troponin, and Tropomyosin Conformational Shifts

Myosin Cross-Bridge Cycling: Power Stroke and ATP Hydrolysis

Phosphocreatine System and ATP Resynthesis During Exercise

Slow-Twitch versus Fast-Twitch Skeletal Muscle Fibres

Investigating Muscle Fatigue and Electromyography

Skeletal Muscle Contraction and Biomechanics

Biomecánica: palancas anatómicas y prevención de lesiones

Neurobiología del ejercicio: endorfinas y neurotransmisores

Neurogénesis, factor BDNF y plasticidad cerebral

Actividad física, regulación del cortisol y manejo del estrés

Biomecánica y neurobiología del ejercicio

Transcription Factors and Promoter Region Binding

Oestrogen as a Lipid Hormone Transcription Regulator

The Lac Operon Mechanism in Prokaryotic Gene Regulation

Second Messengers and Protein Kinase Cascade Activation

Cyclic AMP Activation of Transcription Factors

Epigenetic Mechanisms: DNA Methylation and Gene Silencing

Histone Acetylation and Chromatin Remodelling

Epigenetic Alterations in Carcinogenesis and Oncogene Activation

Regulation of Gene Expression: Transcriptional Control

Prevención de enfermedades crónicas no transmisibles

Sedentarismo: riesgos para la salud y estrategias de vida activa

Sueño, ritmos circadianos y recuperación psicofísica

Salud comunitaria y políticas públicas de deporte y recreación

Ejercicio, salud integral y políticas públicas

Sinapsis, neurotransmisores y el circuito de recompensa cerebral

Mecanismos de tolerancia, dependencia y síndrome de abstinencia

Neurobiología de la cafeína: antagonismo de receptores de adenosina

Efectos fisiológicos del consumo excesivo de cafeína y bebidas energizantes

Nicotina, receptores acetilcolínicos y adicción al tabaco

Química del humo del tabaco: monóxido de carbono y carcinógenos

Patologías asociadas al tabaquismo: EPOC, enfisema y cáncer

Vapeo, cigarrillos electrónicos y nuevos riesgos pulmonares

Neurobiología de las adicciones y toxicología de sustancias legales

Farmacología del alcohol etílico: modulación de GABA y glutamato

Metabolismo hepático del etanol: alcohol deshidrogenasa y acetaldehído

Efectos del alcohol en el desarrollo cerebral adolescente

Drogas psicoactivas: clasificación: depresores, estimulantes y alucinógenos

Cannabis: sistema endocannabinoide, THC y CBD

Opioides, estimulantes sintéticos y crisis de sobredosis

Estrategias de prevención, reducción de riesgos y políticas de salud

Alcohol, sustancias ilícitas y políticas de salud pública

Morfología neuronal y diversidad de células gliales

Potencial de reposo y la bomba Na+/K+ ATPasa

Ecuaciones de Nernst y Goldman-Hodgkin-Katz

Canales dependientes de voltaje y ley del todo o nada

Fases del potencial de acción: despolarización, repolarización y periodos refractarios

OGS.13.LS.6

Aligned learning resources

Related diagrams