Why do you think that some vaccines, such as the flu vaccine, need to be given every year?
2 answers:
Answer:
Because the virus/sickness would evolve and that vaccine might not protect you.
Answer:
Because flu viruses evolve so quickly, last year's vaccine may not protect you from this year's viruses. New flu vaccines are released every year to keep up with rapidly adapting flu viruses.
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D because all the other answer are negative feedback
Answer:
the left hemisphere or side of the brain is responsible for language and speech.
Explanation:
Answer: Psychological effects
Explanation:
The effect is caused by environmental and/or biological factors on individual's social and/or psychological aspects.
Biotic: anything living Abiotic: nonliving stuff like elements in the periodic table