Answer:
1) To form a multicellular organism, a zygote must divide into 16 cells which produces ball structure called a morula. After that, morula is converted into a structure called blastula.
2) Adult stem cells are responsible for the maintenance of tissues and repair the damage tissues in the body. It is also called somatic stem tissue. It increase in number through cell division.
Answer 1: A. Basic
Answer 2: 1. Cell
Answer 3: O. Organ
Hopefully this helps!! (:
The Nervous System coordinates the body's response to environments.
