Final answer:
Increases in population lead to a rightward shift of the demand curve, representing heightened demand for a product across all price points. This shift is graphically shown as a new curve entirely, not as a movement along the existing curve.
Step-by-step explanation:
If the population of potential buyers for a product increases, we model this by shifting the demand curve to the right. This represents an increase in demand, as more people are willing to buy the product at each price level. Demand factors, such as changes in income, the composition or size of the population, tastes and preferences, the prices of related goods, and future expectations, can all cause shifts in the demand curve. Specifically, an increase in people's income generally increases the demand for a product (shifts the demand curve to the right), while a decrease in income would decrease demand (shifts the demand curve to the left).
Let's apply this principle to our scenario: as the population of potential buyers rises, the resulting increased demand for the product shifts the entire demand curve to the right, not to the left, and does not involve moving along the existing demand curve. This represents an enlarged market for the product with a higher quantity demanded at each price point. This graphical representation is critical to understanding how market dynamics can affect the pricing and sales volume of goods and services.