Birds Differ from Earlier Vertebrates by ____

question 5

Multiple Choice

Birds differ from earlier vertebrates by ____.

• A) ​the presence of feathers
• B) ​producing land eggs
• C) ​the ability to maintain a constant body temperature through metabolic activities
• D) ​the ability to fertilize eggs internally
• E) ​their possession of a dorsal nerve cord

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Definitions:

Neurosecretory Cells

Specialized neurons that produce and release hormones into the blood or surrounding tissue, bridging the nervous and endocrine systems.

Pituitary Dwarfism

A condition resulting from insufficient growth hormone production by the pituitary gland, leading to shorter than average height.

Growth Hormone

A hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals.

Melatonin

Pineal gland hormone that regulates sleep–wake cycles and seasonal changes; secreted only in the dark.