The definition of cell theory is as follows: <span>a </span>theory<span> in biology that includes one or both of the statements that the </span>cell<span> is the fundamental structural and functional unit of living matter and that the organism is composed of autonomous </span>cells<span> with its properties being the sum of those of its </span>cells<span>.</span>
From what I understood, the answer is 2a (:
Volcanic activity files the air w carbon dioxide
Answer:
B. The pathogen must be grown in pure culture.
Explanation:
Virus, and also some bacteria can not be cultured in "lifeless media". In the case of bacteria, we refer to the obligate intracellular ones, and all virus. Thus, this postulate can not be fulfilled in all cases. Virus can be propagated on tissue cultures, but certainly this was not considered by Koch. Moreover, these methods often result in spontaneous genetic alterations, which leads to adaptation and even attenuation in animal models of disease, so, the cultured virus perhaps does not induce the same disease when introduced to another specimen.