Answer:
This happens because viruses mutate and vary according to the environment they face. That is why different strains occur and appear every day, which must be updated in the vaccines, in order to have immunity up to date and keep up with the viral mutation without making us sick.
Explanation:
Viruses are acellular structures that do not have their own metabolism or replication method, it is because they must dominate and invade the human body so that its DNA or RNA is coupled to the human and this uses the human machinery to be able to replicate.
On the other hand, as infections occur and viruses appear, they can associate with bacteria forming bacteriophages, they can mutate within an organism that is infected by more than one viral infection and they can even adopt retrovirus mechanisms, which day by day. These new viruses are called as new strains, which evolve and will have to be coupled with vaccines.
Vaccines are a method of natural ACTIVE immunity, that is, part of the virus is inoculated, so that it generates the formation of a specific antibody in the body.
Answer:
google said deep and haw rivers
<span>A custom which allows a man to marry more than one woman is
1. Found in most societies anthropologists have studied.
2. Almost always accompanied by rules which specifies the rights of different wives.
Marrying more than one woman is called polygamy. Most countries allow polygamy marriage while others they don't though we can term marriage as a legal thing. Because it is only in marriage that generations grow.</span>
Answer:
Gas exchange between tissues and the blood is an essential function of the circulatory. The air contains oxygen that crosses the lung tissue, enters the bloodstream, and the alveoli are in direct contact with capillaries of the circulatory system. As water flows over the gills, oxygen is transferred to blood via the veins.
Explanation:
A i think, i mean you get both
