When this part of the eye loses some of its ability to flatten and bulge in order to focus clearly on objects at different distances, we may need eyeglasses

Which of the following explains a neuron's means of encoding various intensities of stimuli?

A. passive conduction B. rate law C. all-or-none law D. electrostatic pressure

Why do rates of alcohol addiction vary among different ethnic populations?

A. Lack of safe drinking water B. Stronger alcohol concentration in spirits consumed in different regions C. Genetics and genetic expression D. Alcohol is cheaper than many healthier beverages