After suffering a brain injury in a motorcycle accident. Arotza cannot form new memories. He can, however, remember events before the accident. Arotza's memory difficulty most clearly illustrates:

bacteria – a word that often brings out a sense of uneasiness in most of us are, in fact, one of the earliest forms of life. it can be quite unnerving to know that there are bacteria all over your skin, hair, and even inside the body. but only a few species of bacteria are dangerous. the majority of bacteria are good, and without them, life on earth wouldn’t be possible. let’s learn more about how are bacteria essential for you to survive.

world war i had a devastating effect on german-americans and their cultural heritage. up until that point   german-americans, as a group, had been spared much of the discrimination, abuse, rejection, collective mistrust experienced by so many different racial and ethnic groups in the history of the united states. indeed, over the years, they had been viewed as a well integrated and esteemed part of american society. all of this change with the outbreak of war.  

explanation:

allergens: overstimulate the nerve system

neurotics: attack nerve cells

mutagens: damage or otherwise alter dna sequence

generators: cause defects during growth and development  

carcinogens: cause unchecked cell growth

i hope you get the idea according to me these are the effects that happened.

it depends on which society you are referring to. many civilization performed rituals so the gods would with their growing season but the most well known is that of the aztecs. they would make sacrifices, usually animals, but sometimes humans as well.