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Cardiac muscle is myogenic. This means signals for contraction and relaxation originate from the heart itself. The process is initiated in the sinoatrial node (SAN), located in the right atrium. The SAN i...
When an action potential reaches the terminal of a pre-synaptic cleft, voltage-gated calcium channels are stimulated to open, causing an influx of Ca+ ions in the pre-synaptic neuron. This infux of Ca+ io...
The phagocyte recognises antigens on the surface of the bacteria as foreign, causing it to be attracted to the bacteria. The phagocyte then engulfs the bacteria, forming a vesicle around it. Lysozomes fus...
Protein structure is determined by amino acid sequence. Each amino acid is coded for by a triplet of RNA bases. These are transcribed from a DNA molecule. If a DNA base is substituted for another base, th...
Deoxygenated blood
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