system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When dentists take X-rays of your mouth, howcome they give you a blanket that blocks your body from the radiation, but they don't give you a skullcap to block your brain?
gpt
They cannot very well block your brain when pushing x-rays through your mouth, but it isn't really important. The radiation isn't really that dangerous and the blanket for your body is more of a precaution than anything. Also radiation is more of a danger for quickly dividing cells in your body such as the bone marrow, small intestines, and the testes/ovaries. Protecting the gastrointestinal organs from radiation exposure is much more useful than cells which divide very slowly such as in the brain, spinal cord, and muscles. The sensitivity of tissues to radiation is called "radiosensitivity" and for the brain it is quite low.