Answer:A. Protists B. Bacteria C. Animals D. Plants E. Fungi F. Archaea
Explanation:viruses are small non-living particles that contains hereditary materials.viruses attack cells of other organisms such as plants , bacteria ,archaea etc.
Viruses are acellular and contains either DNA or RNA.they cannot synthesis protein as they lack ribosomes ,so they use the ribosomes of the cell they have invaded to synthesize they proteins they need.
A virus usually has a central core surrounded by an outer protein coat called capsid.
Viruses can reproduce only within the living host cells and they are specific to the type of cells they attack.they attack plants through insect vectors or through openings on the plants.
Viruses can affect bacteria by injecting their nucleic acids through the cell wall and into the bacteria cell.such viruses are called bacteriophages.
The tRNA molecule determines the type of amino acid!
Answer:
Positive natural selection.
Explanation:
The positive natural selection is a type of natural selection that increases the frequency of an allele or trait when it is advantageous for the population. What happened in the example is that the mouth with the slight change in morphology (trait) was more advantageous for the population in the south in relation to the ancestral morphology (still preserved in the population in the north), and therefore its frequency increased. This, in turn, is due to the fact that the food (prey) is not the same in the two habitats (north and south). The specific prey in the south, caused the new morphology to be selected, (increasing the frequency of individuals with the new mouth), becasue probably that trait allows the trouts in the south to hunt more effectively.