Why do red blood cells have no nucleus?

Microorganisms aren’t all decomposers; in fact, many act as producers or primary consumers in an ecosystem. how do microorganisms that act as producers benefit the rest of an ecosystem in terms of energy transfer? what about microorganisms that act as primary consumers?

Animals such as pronghorn antelope, bison ans badgers dot to the landscape. where are these animals located?

This is the amino acid cysteine. circle the amine group, put a box aroundthe carboxylic acid group and use a different colored pencil/pen to circle the sidechain (r group). h o | ||nh2— c- c-oh | ch2 | sh