def prc_list(mod):
    """
    Retuns a list of partial response coefficients of a model.

    The list contains both species and flux partial response coefficients and
    partial response coefficients follow the syntax of
    'prc_responder_parameter_route'.

    Parameters
    ----------
    mod : PysMod
        The Pysces model contains the reactions, species and parameters
        which is used to construct the partial response coefficient list.

    Returns
    -------
    list of str
        The prc_list is sorted alphabetically.

    See Also
    --------
    cc_list, ec_list, rc_list

    """
    prcs = []
    for base_param in mod.parameters:
        for back_reaction in mod.reactions:
            for top_species in mod.species:
                prc = 'prc%s_%s_%s' % (top_species, base_param, back_reaction)
                prc = str(prc)
                prcs.append(prc)
            for top_reaction in mod.reactions:
                prc = 'prcJ%s_%s_%s' % (top_reaction,
                                        base_param,
                                        back_reaction)
                prc = str(prc)
                prcs.append(prc)
    prcs.sort()
    return prcs