In a Comparison of Birds and Mammals, Having Four Limbs

question 45

Multiple Choice

In a comparison of birds and mammals, having four limbs is

• A) a shared ancestral character.
• B) a shared derived character.
• C) a character useful for distinguishing birds from mammals.
• D) an example of analogy rather than homology.
• E) a character useful for sorting bird species.

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Definitions:

Hemocyanin

A copper-containing protein found in the blood of some invertebrates, such as mollusks and arthropods, responsible for transporting oxygen.

Erythropoietin

A hormone produced by the kidneys that stimulates the production of red blood cells in response to low oxygen levels in tissues.

Mammalian Red Blood Cells

Mammalian red blood cells are biconcave, disk-shaped cells that carry oxygen from the lungs to the body's tissues and remove carbon dioxide, lacking a nucleus when mature.

Phagocytic

Pertaining to cells that have the ability to engulf and absorb particles or other cells through a process called phagocytosis, key for immune defense.