Ethan is modeling food chains he observes in his local ecosystem. Which of these models represent possible food chains he might observe? Select all that apply. A. primary producer -> consumer -> consumer -> consumer -> consumer
B. primary producer -> consumer -> primary producer -> consumer
C. primary producer -> consumer -> consumer
D. consumer -> primary producer -> consumer -> primary producer -> consumer
E. consumer -> consumer -> consumer -> consumer

About __ of the mass of the cell is water

What is the significance of the protein-lined pits? a. protein attracts other proteins needed for atp synthesis within the cell. b. protein-lined pits are able to transport one molecule at a time down the concentration gradient within the cell. c. the polarity of proteins allows other polar molecules to attach and be transported in the cell by transport channels. d. receptors within the pits allow ligands to fuse and be transported into the cell by endocytosis.

Which of the following are not included as modern mammals that evolved during the eocene epoch? primates artiodactyls perissodactyls none of the above