Probably becauase stream pools are in motion.
Ingestion of foreign substances by macrophages and yeast cells by an amoeba is known as <u>Phagocytosis</u>
<u>Explanation:</u>
Phagocytosis that is the name given to the process of ingestion of foreign particles by macrophages. In human body the white blood cells does this function. Macrophages is found in all the tissues. Any foreign particle entering the body is engulfed by this process hence protecting the organisms.
Once a bacteria enters the body it is at once detected and recognised as the foreign particle. Then it is attached to the phagocyte. Then it is engulfed into a vesicle called phagosome. Then this is killed by the process of phagocytosis.
Answer: Both infect host organisms
Explanation: A virus is a microscopic particle that can infect the cells of a biological organism. ... They are similar to obligate intracellular parasites as they lack the means for self-reproduction outside a host cell, but unlike parasites, viruses are generally not considered to be true living organisms.