Our Nation

question 142

Multiple Choice

Our nation

• A)has sometimes attained productive efficiency.
• B)usually attains productive efficiency.
• C)never attained productive efficiency.

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Definitions:

Diffusion

Movement of molecules or ions from a region of higher to lower concentration; it requires no energy and tends to lead to an equal distribution (equilibrium).

Urinary System

Organ system of humans that includes the kidneys, urinary bladder, and associated structures; excretes metabolic wastes; maintains fluid balance; helps control pH.

Blood Ph

The measure of acidity or alkalinity of blood, maintained within a very narrow range, essential for physiological processes.

Nitrogenous Wastes

Waste products containing nitrogen, such as urea and ammonia, excreted by living organisms.