Answer:
A radioactive (unstable) phosphorus isotope is made to replace a nonradioactive isotope of phosphorus in the molecule
Explanation:
Phosphorus has both unstable (radioactive) and stable isotopes. In any compound that contains phosphorus, the phosphorus atom present may be either a stable isotope of phosphorus or an unstable isotope of phosphorus.
However, if the molecule contains a stable nonradioactive isotope of phosphorus, it is possible to convert this isotope in the molecule to the unstable radioactive isotope by carefully carrying out exchange reactions in which the phosphorus isotope replaces the nonradioactive isotope in the molecule.
This is usually done in order to create radioactive tracers which are used to study chemical reactions and biochemical processes.
D-a trait that helps an organism survive in its environment
The hypothesis devised in this study by the researcher is –
" White fly nymphs escape predation because of their translucent bodies."
In order to test this hypothesis, the researcher is required to conduct an experiment where two sets of white fly nymphs are formed and fed to their predators. The two set of subjects would be -
Set I – White fly nymphs with translucent bodies
Set II- White fly nymphs with translucent bodies coated with harmless dyes.
The number of predated flies in each set can be compared to deduce justification for assumed hypothesis.
Hence, option B is correct
The squirrels are attuned in their brains to understand that owls are a threat because it is a predator. This is visual stimuli that evolved over many years to elicit a conditioned response. This is an innate behavior (meaning that it has been pre-programmed into an animal's genes) and offspring are naturally born with it.
Prairie dogs with established burrows
