def METHOD_NAME(morpho, axis, color_switch=False):
    if isinstance(morpho, Soma):
        ax.plot(morpho.x/um, morpho.y/um, 'o', color='darkred',
                ms=morpho.diameter/um, mec='none')
    else:
        coords = morpho.coordinates
        if color_switch:
            color = 'darkblue'
        else:
            color = 'darkred'
        ax.plot(coords[:, 0]/um, coords[:, 1]/um, color='black',
                lw=2)
        # dots at the center of the compartments
        ax.plot(morpho.x/um, morpho.y/um, 'o', color=color,
                mec='none', alpha=0.75)
    for child in morpho.children:
        METHOD_NAME(child, axis=axis, color_switch=not color_switch)