Final answer:
Quantity demanded refers to the amount of a product that consumers are willing to purchase at a certain price, which represents a specific point on the demand curve. Demand is the broader concept that includes the entire range of price-quantity relationships shown on the demand curve.
Step-by-step explanation:
The term "quantity demanded" refers to the amount of a product that will be purchased at some specific price. This is different from demand, which refers to the entire relationship between a range of prices and the quantities that consumers are willing to buy at those prices. This relationship is typically illustrated through a demand curve or a demand schedule. Thus, while the demand curve represents the broad relationship of prices and quantities, quantity demanded pinpoints a specific quantity on that curve at a given price.
For example, a demand schedule can display various prices and their corresponding quantities demanded. When we plot this information on a graph, the demand curve emerges, showing the whole spectrum of price-quantity relationships. However, quantity demanded represents individual points on this demand curve, corresponding to a particular price.