Birds Generate a Lot of Heat, Especially During Flight

question 30

Multiple Choice

Birds generate a lot of heat, especially during flight. Yet the adipose tissue under their skin and the feathers atop their skin make it difficult to eliminate excess heat across the skin. Which of the following can absorb body heat and eliminate it from the bird most effectively?

• A) lymph in the lymphatic vessels
• B) blood in the heart
• C) blood in the vessels
• D) urine in the bladder
• E) air in the air sacs

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Definitions:

Tectonic Forces

Forces generated by the movement and interaction of the Earth's lithospheric plates, responsible for shaping the earth's surface.

Wall Rocks

The rocks surrounding an igneous intrusion or a mineral deposit.

Dikes

Vertical or steeply inclined sheet-like bodies of igneous rock that cut through sedimentary rock layers.

Intrusive Rock

Igneous rock formed from magma that cools and solidifies within the crust of the planet, creating large crystal grains.