def tissue_vol_in_samp_gr(term_vol_in_grid, br_vol_in_grid):
    """Calculate the total tissue volume (i.e. including terminal conduits) of tree branches

       Inputs are:
       - term_vol_in_grid:total volume of terminal conduits
       - br_vol_in_grid:total volume of branches before terminal conduits

       Return:
       tissue_vol: total tissue volume of whole tree
      
       A way you might want to use me is:

       >>> term_vol_in_grid=0.444
       >>> br_vol_in_grid=0.008

       This will return:
       >>> tissue_vol: 0.452"""

    tissue_vol = br_vol_in_grid + term_vol_in_grid

    return tissue_vol