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10 Cards in this Set

  • Front
  • Back
What features of birds enable them to live on land?
lungs, wings, legs, beaks, internal fertilization, shelled, amniotic eggs, endothermic metabolism
Describe how a bird’s respiratory system works, and explain how air sacs improve a bird’s ability to obtain the energy necessary for flight.
Oxygen can enter a birds circulatory system when it inhales and exhales. Inhalation results in oxygen entering the lungs then entering air sacs. When a bird exhales, oxygenated air in the air sacs passes into the lungs, thereby increasing the amount of oxygen available to the bird to generate energy neede for flight.
What is an endotherm? How does being an endotherm have adaptive value for birds that live in polar regions?
Endotherms can regulate their body temperature regardless of the outside temperature
Analyze the relationship between modern birds and dinosaurs.
Most scientists think that modern birds evolved from theropod dinosaurs.
Large, flightless birds once were common in areas that did not have large, carnivorous predators. Many of these birds are now extinct. Form a hypothesis about the evolution and extinction of large, flightless birds.
Large flightless birds evolved in regions where there were few large carnivores. Extinction was probably caused by the introduction of large, carnivorous predators.
Summarize the adaptations birds have that enable them to fly.
-Feathers keep bird insulated and able to fly
-Wings generate lift needed for flight
-Four chambered heart pumps rapidly, giving energy and oxygen needed for flight
-Respiratory system constantly gives bird oxygen in the lungs, which gives it energy for flight
-Endotherms, allows them to maintain high energy levels needed for flight
lightweight, modified scale found only on birds; provides insulation and enables flight.
large breastbone that provides a site for muscle attachment; provides support for the thrust and power produced by birds as they generate motion for flight.
animal that maintains a constant body temperature and is not dependent on the environmental temperature.
process of keeping eggs laid outside of the body warm; also involves periodic turning of the eggs to ensure proper development.