When geneticists are looking for genes linked to particular disorders, such as cardiomyopathy, why is it important that they look at healthy individuals in addition to individuals affected by the disorder?

Because Healthy individuals provide a baseline or foundation for comparison.

passive transport is a movement of biochemicals and other atomic or molecular substances across cell membranes without need of energy input. unlike active transport, it does not require an input of cellular energy because it is instead driven by the tendency of the system to grow in entropy.

so, according to what that says, i believe it's hypertonic and hypotonic.

good luck!