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  <head>
    <title>002-01 Foundations</title>
    <ownerName>Integrated Medical Foundations</ownerName>
  </head>
  <body>
    <outline text="Membranes, signalling, and excitable cells">
      <outline text="Resting potential and the action potential">
        <outline text="Potassium high inside, sodium high outside"/>
        <outline text="Selective permeability and the sodium-potassium pump">
          <outline text="Inside negative relative to outside"/>
        </outline>
        <outline text="Graded potential scales with stimulus strength"/>
        <outline text="Threshold at trigger zone opens sodium channels">
          <outline text="Sodium entry produces the rising phase"/>
        </outline>
        <outline text="Sodium inactivation and potassium efflux repolarise">
          <outline text="Continued potassium conductance: brief hyperpolarisation"/>
        </outline>
        <outline text="All or none: stronger input raises frequency, recruitment"/>
      </outline>
      <outline text="Refractoriness and propagation">
        <outline text="Absolute refractory: inactivated sodium channels">
          <outline text="Cannot reopen even with a strong stimulus"/>
        </outline>
        <outline text="Relative refractory: potassium conductance persists">
          <outline text="A stronger input may succeed"/>
        </outline>
        <outline text="A changing molecular state, not energy exhaustion"/>
        <outline text="Refractoriness limits rate, enforces one-way travel"/>
        <outline text="Local current depolarises adjacent membrane">
          <outline text="Signal regenerated, ions not carried as a packet"/>
        </outline>
        <outline text="Myelin: saltatory conduction, renewed at each node"/>
      </outline>
      <outline text="Synapses and autonomic control">
        <outline text="Presynaptic calcium entry triggers release"/>
        <outline text="Ionotropic receptors: direct channels, fast"/>
        <outline text="Metabotropic receptors: pathways, slower, longer"/>
        <outline text="Excitatory potential moves toward threshold"/>
        <outline text="Inhibitory potential moves away or stabilises"/>
        <outline text="Spatial and temporal summation integrate inputs"/>
        <outline text="Autonomic control of cardiac, smooth muscle, glands">
          <outline text="Sympathetic mobilises, parasympathetic conserves"/>
          <outline text="Coordinated tendencies, many organs dual input"/>
        </outline>
      </outline>
      <outline text="Hormone classes and feedback">
        <outline text="Act only on cells bearing receptors"/>
        <outline text="Peptides and catecholamines: water-soluble">
          <outline text="Membrane receptors and second messengers"/>
        </outline>
        <outline text="Steroid and thyroid hormones: lipid-soluble">
          <outline text="Intracellular receptors alter gene expression"/>
          <outline text="Slower onset, longer lasting"/>
        </outline>
        <outline text="Thyroid axis: releasing hormone, stimulating hormone">
          <outline text="Rising thyroid hormone inhibits both levels"/>
        </outline>
        <outline text="Insulin and glucagon act antagonistically">
          <outline text="Insulin: uptake and glycogen, fat, protein synthesis"/>
          <outline text="Glucagon: glycogen breakdown and gluconeogenesis"/>
        </outline>
        <outline text="Adrenal medulla fast, cortisol axis slower"/>
      </outline>
      <outline text="Neural and endocrine integration">
        <outline text="Neurons: targeted, milliseconds to seconds"/>
        <outline text="Hormones: broad, seconds to days"/>
        <outline text="Hypothalamus converts neural input to endocrine output"/>
        <outline text="Hormones alter brain function and behaviour"/>
      </outline>
      <outline text="Sensory coding">
        <outline text="Transduction of energy into electrical signals"/>
        <outline text="Receptors selective rather than perfectly specific"/>
        <outline text="Intensity: firing frequency and recruitment"/>
        <outline text="Location: receptive field and pathway"/>
        <outline text="Adaptation reduces response to constant stimuli">
          <outline text="Rapid adapters signal change and vibration"/>
          <outline text="Slow adapters report magnitude or position"/>
        </outline>
        <outline text="Pain sensitises after injury">
          <outline text="Mediators and central pathways lower thresholds"/>
        </outline>
      </outline>
      <outline text="Motor hierarchy and reflexes">
        <outline text="Spinal circuits: reflexes and patterned activity"/>
        <outline text="Brainstem: posture, balance, eyes, breathing"/>
        <outline text="Cortex plans, basal nuclei select and scale"/>
        <outline text="Cerebellum compares intended with actual movement"/>
        <outline text="Stretch reflex: spindle excites same-muscle neurons">
          <outline text="Reciprocal inhibition of the antagonist"/>
          <outline text="Descending pathways adjust reflex gain"/>
        </outline>
      </outline>
      <outline text="Endocrine axes in detail">
        <outline text="Concentration: secretion, binding, metabolism, excretion">
          <outline text="Bound fraction a reservoir, free fraction acts"/>
          <outline text="Pulsatile and circadian timing matter"/>
        </outline>
        <outline text="Cortisol axis: releasing hormone to cortisol">
          <outline text="Excess: muscle breakdown, hyperglycaemia, bone loss"/>
          <outline text="Deficiency: poor pressure support and stress tolerance"/>
        </outline>
        <outline text="Growth hormone pulses, drives insulin-like growth factor 1"/>
        <outline text="Prolactin tonically inhibited by dopamine"/>
        <outline text="Low calcium stimulates parathyroid hormone">
          <outline text="Kidney keeps calcium, loses phosphate"/>
          <outline text="Active vitamin D raises gut absorption"/>
        </outline>
      </outline>
      <outline text="Receptors, interaction, and plasticity">
        <outline text="Response: concentration, receptors, affinity, machinery">
          <outline text="Saturation flattens the dose-response"/>
          <outline text="Spare receptors allow maximal response"/>
        </outline>
        <outline text="Permissive, synergistic, antagonistic interactions">
          <outline text="Thyroid hormone permits catecholamine response"/>
        </outline>
        <outline text="Disease: excess, deficiency, resistance, feedback loss">
          <outline text="Primary failure: low thyroid, high stimulating hormone"/>
          <outline text="Pituitary failure: both inappropriately low"/>
        </outline>
        <outline text="Plasticity: synapses strengthen or weaken">
          <outline text="Long-term memory needs gene expression"/>
          <outline text="Can sustain chronic pain, addiction, fear"/>
        </outline>
      </outline>
    </outline>
  </body>
</opml>
