The Example of Ocean and Lake Stickleback Fishes Indicates That

question 66

Multiple Choice

The example of ocean and lake stickleback fishes indicates that morphology can be altered

• A)by altering the expression of a developmental gene in some parts of the body but not others.
• B)by environmental factors (in this case,pollution).
• C)by the elimination of a gene (Pitx1)from a population,which leads to loss of the trait (body armor and spines).
• D)only by changing the sequences of protein- coding genes.

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Definitions:

Short-Run Supply Curve

A supply curve that shows the quantity of a product a firm in a purely competitive industry will offer to sell at various prices in the short run; the portion of the firm’s short-run marginal cost curve that lies above its average-variable-cost curve.

Marginal Cost Curve

A graph that shows the relationship between the marginal cost of producing an additional unit and the quantity of that unit produced.

Supply Curve

A visual chart that illustrates how the price of an item correlates with the amount of the item that sellers are prepared to offer.

Marginal Cost Curve

A graphical representation showing how the cost of producing one more unit of a good or service changes as production volume increases.