Which vitamin requires intrinsic factor in order to be absorbed?
a. b12
b. k
c. a
d. c

Vitamin B12-- without it, it could be destroyed by the digestion process

Eukaryotic cells are theorized to have evolved from prokaryotes called the endosymbiotic theory. this explains that the most primitive eukaryotic cell engulfed a prokaryotic cell (by the process of phagocytosis) that is capable of cellular respiration and another prokaryotic cell that is capable of photosynthesis. these prokaryotic cells eventually became organelles and these organelles are the mitochondria and the chloroplast