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Meristem size is a very controled, highly genetic feature. It doesn't change between big or small branch/root (The SAM and RAM are obviously different). There are very levels of potency in the meristematic tissue, so you should explain more which section of the meristem is of interest. SAM (shoot apical meristem) In *Arabidopsis thaliana* there are 9 long-...


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SHORT ANSWER: They are basically the same thing physically. LONG ANSWER: Depolariation is a feature of any excitable tissue. Heart is no exception. But the striking feature of Heart is that it can produce periodic depolarisation waves (With a defined Time Period). This ability of heart is due to certain modified myocardial cells, which are called conducting ...


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Depolarisation of nerve (here Purkinje fibres) causes Action Potential (bcoz of opening of voltage gated Na channels) which causes opening of Ca++ channels in membrane of heart muscle- results in ventricular contraction So ventricular depolarisation is actually action potential in heart muscle of ventricles So both terms are related Ventricular ...


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Graphs like these are based on a complete cross-sectional area. Myelination adds thickness, so if you want to add myelin outside and keep the same diameter, you have to have a smaller lumen inside the axon. As you can see in the "unmyelinated" plot versus diameter, smaller fibers have lower conduction velocity. Since the benefits of cross-sectional ...


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That's observed due to passive conduction. With more area of cross section resistance is decreased (ohm's law). Myelin has just function of insulation the graph showing conduction in neuron fibre varying with thickness of neuron (hereby also thickness of myelin sheath). Conduction is ruled by multiple factors not only just thickness of insulation. check this ...


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I would say that the quoted sentence from the Wikipedia gemmule article is wrong. The first sentence of the containing paragraph says: Asexual reproduction in sponges occurs via budding, either by external or internal buds. At face value, the two sentences together imply that sponges can reproduce by external budding, but that the external budding "...


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