<span>They do not possess any skeleton at al</span>
Answer:
More info given below.
Explanation:
This attraction occurs as a result of static charge. You see an atom is referred to as the smallest particle of a substance; and when an atom gains or looses electrons it becomes unstable creating a difference in potential. However in this case rubbing induces friction which induces heat. This heat excites the atom to loose electrons creating a negative charge on the silk and a converse positive charge on the pencil.
Answer:
Birds require high levels of oxygen and, therefore, high rates of gas exchange due to flight demands. Avian resting oxygen consumption is high compared to that of mammals and other vertebrates, and this increases even more during the flight.
Explanation:
Compared to mammals, birds have specific adaptations of the respiratory system that result in higher levels of oxygen exchange.
