Which statement best describes the purpose of Earth's spheres? They work together as open systems to cycle matter through ecosystems.
They work independently as closed systems to cycle matter through ecosystems.
They work together as open systems to move matter to living and nonliving parts of Earth.
They work independently as closed systems to move nutrients to living and nonliving parts of Earth.

A.They work together as open systems to cycle matter through ecosystems.

Explanation:

i did it on edge

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.

condensation. good luck!