Proteins comprise what percentage of our body cell mass?

Which best describes red blood cells? a. they are colorless b. they protect against disease-carrying microorganisms c. they transport oxygen throughout the body d. they aid in blood clotting

How did the research presented in the article affect scientists' understanding of the evolution of eukaryotes

1. which of the following transport mechanisms utilizes energy? a. osmosis b. diffusion c. facilitated diffusion d. endocytosis