Which of the Following Statements Comparing Respiration in Fish and in Mammals

question 63

Multiple Choice

Which of the following statements comparing respiration in fish and in mammals is correct?

• A) The respiratory medium for fish carries more oxygen than the respiratory medium of mammals.
• B) A countercurrent exchange mechanism between the respiratory medium and blood flow is seen in mammals but not in fish.
• C) The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional.
• D) In blood, oxygen is primarily transported by plasma in fish, but by red blood cells in mammals.

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Definitions:

Marginal Costs

The supplementary cost arising from the manufacture of an extra unit of a good or service.

Variable Inputs

Inputs that can be adjusted in the short term to alter the level of output in the production process.

Marginal Cost Function

A mathematical representation showing how the cost of producing one additional unit of a good changes as production volume changes.

Optimal Output

The level of production that maximizes a firm’s profit or minimizes its cost under given conditions.