The quantities in the table represent one Zone block for the food's particular macronutrient group, which approximate the amounts that will supply either 9g of carbs, 7g of protein, or 3g of fat.
There's more info on the Zone Food Block system here.
It's a bit different to the books
Those of you familiar with Zone foods lists will notice that fat is 3g per block in this table instead of 1.5g like in Dr Sears' books. Dr Sears set lower fat quantities in his lists because of the assumption that we'll nearly always get some extra fat from our protein source.
Also, the data is from our local FSANZ database so there may be some slight differences to the American books based on the USDA data. If you find any huge differences please let me know...
But don't stress
The block method isn't meant to be a nightmare, I want to stress that neither Dr Sears or myself recommend fastidiously measuring food to the nearest gram, these values are just presented as a guide to get you in the right ballpark.