A mature human red blood cell has no nucleus or mitochondria. It consists primarily of a membrane and surrounding hemoglobin. What are some advantages of the simple organization of human red blood cells?

i think it would be b. tissue because an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.

if you look up in the top right corner you'll see your current profile picture, click than click "view profile" you'll be able to change it there.

the alkaline earth metals (beryllium (be), magnesium (mg), calcium (ca), strontium (sr), barium (ba), and radium (ra)) are a group of chemical elements in the s-block of the periodic table with very similar properties: shiny. silvery-white. hopefully this ? i didn't fully understand the question