In general, plant proteins are used efficiently as animal proteins to build proteins in the human body.

In general, plant proteins are used less efficiently as animal proteins to build proteins in the human body.
This is because there are many differences between plant proteins and animal proteins - primarily those concerning the combinations of amino acids. Plant proteins have such combinations that do not allow them to be as efficient as proteins found in animals.

The category is the thing that is most simmilar throughout a period