Which Statement About Gill Ventilation in Fishes Is False

question 124

Multiple Choice

Which statement about gill ventilation in fishes is false?

• A) In some species, gill ventilation occurs via open-mouth swimming.
• B) In most species, gill ventilation occurs via a two-pump mechanism.
• C) During an expiration by a fish using the two-pump mechanism, the mouth cavity contracts, forcing water over the gills.
• D) During an inspiration by a fish using the two-pump mechanism, the opercular cavity expands and the opercular flaps are kept closed.
• E) Tunas use the two-pump mechanism.

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Definitions:

Average Variable Cost

Average Variable Cost is calculated by dividing the total variable costs of production by the quantity of output produced; it varies with production levels.

Monopolistically Competitive

A market structure where many companies sell products that are similar but not identical, allowing for some degree of market power and price control by individual firms.

Profit-Maximizing Level

The optimal point at which the difference between total revenue and total cost is the greatest, indicating the highest possible profit for a firm.

Short Run

a period in economics during which at least one input is fixed and cannot be changed, limiting a firm's ability to adjust production.