Answer:
except natural killer cells.
Explanation:
The Helper T cells produce cytotoxic T cells and help B cells, but not natural killer cells
The brain and the spinal cord.
Scientists use labs to Design and Carry out experiments.
Answer: False
Explanation: Defines the procedures to be followed for the administrative operation and organization of the institution, the implementation of rules, and the imposition of sanctions on those who violate or do not fully conform to relevant laws.