The muscles surrounding the airways contract
Answer:
is an informal term for a group of single-celled eukaryotes, either free-living or parasitic, which feed on organic matter such as other microorganisms or organic tissues and debris. ... Some examples of protozoa are Amoeba, Paramecium, Euglena and Trypanosoma.
Thousands of Americans are on the Waiting list for an Organ Transplant.