Hummingbirds need large amounts of energy to flap their wings between 60
and 200 times per second. Their wings beat so rapidly that it is difficult to see
them move. They often appear suspended in air for extended periods of time
without changing their location. Hummingbirds have long bills and grooved
tongues to reach into flowers to feed on flower nectar.
Which two body systems are involved based on the information above?
Select one:
•
skeletal and muscular
•
skeletal and endocrine
•
skeletal and digestive
skeletal and circulatory