Which of the following statements about the clonal-selection theory of immune system function is false?

antigens are recognized by receptor proteins inside the lymphocyte.
an activated lymphocyte makes many copies of itself in response to an infection.
each lymphocyte recognizes one antigen.

What is the broadest level of classification of life

25) a student takes four samples of a white crystalline solid and places each in a well plate. on top of each sample, she carefully places 20 drops of clear mystery liquids a, b, c and d. her results for each well are: liquid a: the solid dissolves quickly. liquid b: the solid appears unchanged. liquid c: a brownish colored liquid is produced. liquid d: fizzing occurs and the well becomes warmer. in which well does a physical change occur?

During which phase does earth see more than half of the moon's surface? 1)first quarter2)third quarter3)waxing gibbous4)waning crescent