isotopes
TRANSCRIPT
•neutrons “fall off”•emission can be detected and traced•molecules “decay” into another kind of molecule
Some are radioactive and some are stable.
•neutrons “fall off”•emission can be detected and traced•molecules “decay” into another kind of molecule
•neutrons stay put•remain as they are over time
Some are radioactive and some are stable.
Monarch Migration video (NOVA)
http://www.pbs.org/wgbh/nova/nature/journey-butterflies.html
Until now, there's never been a good way to find out exactly where the Mexican monarchs spend their summers and reproduce. Butterfly tagging programs are popular. But only a few tagged butterflies are found among the millions of monarchs in the wintering grounds. Butterflies are too small to track with radios or satellites.
In nature, an element occurs as a mixture of isotopes which can vary according to geography and other environmental factors
How can isotopes be used to study monarch migration?
Researchers analyze wing membranes because their isotopic composition does not change after they are formed at the breeding site.
radioactive isotopes can be used to:
•trace atoms in metabolism•diagnose medical disorders•monitor chemical processes in the body
Which oxygen isotope gets trapped in ice (as a result of precipitation) and in the shells of ocean organisms is temperature dependent so . . .
Which oxygen isotope gets trapped in ice (as a result of precipitation) and in the shells of ocean organisms is temperature dependent so . . .
ratios can be used to determine past temperatures
ratios can be used to determine past temperatures
Uses for isotopes:•tracking migration•medical uses•forensic uses•environmental changes (like climate changes and pollution movement)•radioactive isotopes can be used for aging things