One positive choice someone can make to help their health would be to exercise if you are overweight. One negative choice someone can make that can worsen their health would be drinking any alcohol. Exercising when overweight can help your health by decreasing chances of heart diseases and drinking any alcohol to an excessive extent can harm your liver which can lead to death or a journey of pain and complications.
POSITIVE: a positive choice would include is if someone is gaining so much weight, they can start a diet or an exercise plan. Due to this they will control their weight and won't get diabetes(from junk food sugar candy etc.)
NEGATIVE: a negative choice is to smoke which would cause lung problems. People smoke because they have an addiction, and they just can't stop. later on you can die due lung issues.
Both "depends upon the binding of that substance to a specific site on the membrane protein" and "depends upon movement of proteins from one side of the membrane to the other" are correct.
The saturation effect prevents statement 2 from being true.
