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species – n. a set of plants or animals in which the members have similar characteristics to each other
outbreak – n. the sudden appearance of a contagious illness
sample – n. a small amount of a substance collected by a scientist or doctor
veterinarian – n. someone whose job is to give medical care to animals that are sick or hurt
mutate – v. biology : to cause (a gene) to change and create an unusual characteristic in a plant or animal
pandemic – n. the spread of an infectious disease over a large area in a short period of time
vigilant – adj. watching something carefully and always being ready to notice anything unusual or dangerous
surveillance – n. the activity of watching people carefully, often secretly, especially by an army or police force
