Once a hypothesis is tested and confirmed, and then tested again and confirmed again by many others, it may provide the basis for, or become a part of, a scientific theory.
Mitosis has four stages. They are the prophase, the metaphase, the anaphase, and the telophase.
Answer:
The complement system is a <u>biological</u> barrier of the immune system.
Explanation:The answer is biological for edgeunity
