The bile is produced by the liver and the gallblader only serves as storage between meals. The main stimulus for the release of bile from the gallblader comes from the nervous system,after food is put in the mouth.
Answer:
The correct answer is organisms that have extreme traits. Explanation: Disruptive selection is a specific type of natural selection that describes changes in population genetics. In disruptive selection, both extreme values for a trait are favored over intermediate values.
Explanation:
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.
Answer:
Maybe this helps! Atoms come together to form molecules because of their electrons. Electrons can join (or bond) atoms together in two main ways. When two atoms share electrons between them, they are locked together (bonded) by that sharing. These are called covalent bonds.