Radiosensitivity is an important topic.
Do learn these important one-liners related to Radiosensitivity.
BOILS
Bone Marrow
Most Radiosensitive Tissue
Ovaries
Most Radiosensitive Gonads
Intestinal Mucosa
Most Radiosensitive Mucosa
Lymphocyte
Most Radiosensitive Cell
Skin
Most Radiosensitive Organ

Hope that mnemonic helped. Got a better mnemonic for the same? Let us know in the comments below.
Also check out these medical mnemonics