A A
is a hypothesis or set of hypotheses that is accepted to be true based on observations and repeated experimentation with similar results.

How can antibodies "remember" a particular bacterial invader or "antigen" on that invader?

Need the diagram below, which is not drawn to scale, shows the position of the earth, moon, and sun. what type of eclipse occurs when the earth, moon, and sun are lined up in the order shown? a. planetary eclipse b. solar eclipse c. martian eclipse d. lunar eclipse

Nucleic acids offer variability because they contain alternate forms of genes called .