Warren finds an unusual star-shaped creature in the bottom of a tide pool while walking along a rocky beach. which question about the marine creature cannot be answered through scientific investigation?
a.
is the creature a plant or an animal?
b.
is the creature native to these parts or has it been introduced into the area?
c.
is it the most unusual living creature in the area?
d.
what does the creature feed on?

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.

a tetrad is the foursome during meiosis made by two homologous chromosomes that have each already replicated into a pair of sister chromatids.