Proteins that tag pathogens for destruction by immune cells are called
a. antibodies
b. antigens
c. histamines
d. interferons

Which strategy is an example of how companies may upgrade themselves to meet changing customer preferences? a. doing door-to-door sellingb. using billboards to advertise the productsc. making online shopping services availabled. giving discounts on products

Apopulation of black bears depends on salmon from a stream for food. if a drought causes the stream to run dry one year, how will this likely impact the black bear population?

(amoeba sisters video recap: pedigrees and need