Use words from the box to complete the sentences about the control and safety of nuclear fission within a nuclear power reactor.
| boron | control rods | coolant |
| fast | moderator | slow |
| turbine |
To sustain a controlled fission chain reaction, a .......... is used to reduce the kinetic energy of fission neutrons so they can be captured by uranium-235 nuclei.
The rate of reaction is managed by adjusting the depth of the .......... which absorb excess neutrons to prevent an uncontrolled reaction.
The thermal energy produced by fission is transferred away from the reactor core by the .......... to eventually turn steam turbines.