Radioactive elements are produced in nature and scientific experiments.

Sufficient caution is necessary when handling radioactive materials.

This area is off-limits due to high radiation levels.

This radio is emitting music.

Sex chromosomes play a crucial role in determining the sex of an organism.

The environmental issues are becoming more serious.

Environmental issues are becoming more serious day by day.

This area is affected by radioactive fallout from past nuclear tests.

An isotope refers to elements with the same atomic number but different numbers of neutrons.

His body is very healthy.