Because bacteria mutates that's why we have a new flu vaccine every year , because strains of DNA in the bacteria change all the time.
Answer:
In general, a scientific law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. The explanation of a phenomenon is called a scientific theory
Explanation:
Cellular respiration occurs in all eukaryotic cells, both animal and plant cells.
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hope i helped my dewd <3
