What does the presence of soil indicate about an area that is experiencing ecological succession? Choose the correct answer.

The process is unchanging.

The process is eutrophication.

The process is secondary succession.

The process results in a catastrophic change.

Which part of cellular respiration must occur before any of the other steps can occur

When a person is exercising the body needs to deliver increased amounts of oxygen to the muscles which component of blood ensures that the muscles will receive it

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.