What do the orange and yellow spheres represent in this model of an atomic nucleus?[Atomic nucleus] A Gluons and leptons
B Protons and neutrons
C Positrons and electrons
D Atoms and molecules

it would be c. xylem.

answer; i believe its (ovulation);

trachea, alveoli, lung capillaries, arteries

i'm guessing this is from edg enuity so the answers would be, from top to bottom,

theodor schwann

matthias schleiden

robert hooke

rudolph virchow

anton van leeuwenhoek