Answer:
population mating structure and culture. hopefully I'm right.
No, although there are several theories with increasing evidence, there is still no way to know for sure how it occurred. The great mystery of the beginning of universe is way too vast and vague. Theories can only be proven by presenting a solid proof, but great creations such as universe itself doesn't have to be solved. Various possibilities must have happened or there must be a one conclusion leading to its existence; but moreover, it is not our problem to solve. The confirmation of beginning of its existence will only feed the curiosity of humans.
And no, procaryotes can not be multicellular, but that is not a rule, since scientists have been getting more and more evidence that procaryotic organisms can exist.
→ Note - there is no such thing as multicellular cells, but multicellular tissues/organisms.
Hope it helped,
BioTeacher101
Research indicates that stress can produce direct physiological effects such as elevated blood pressure, increased hormonal activity, and decrease in immune system functioning. Or, in other words, all except psychological disorders.
