15. When red blood cells mature, most of the organelles are removed to make space for as many hemoglobin molecules as possible. The removal of the nucleus would also result in the removal of the cell’s A ribosomes B genetic material C proteins D outer membrane

1. in what ways have non-native species been beneficial? 2. what are some of the hypotheses for the collapse of honeybee colonies? 3. distinguish between regional and functional extinction. 4. why is it difficult to measure background extinction rates? 5. what three factors are most important in causing extinction rates to climb?