The external ear structure is called the Pinna.
The Pinna helps to channel sound waves into the ear.
Many animals have the ability to move their pinna towards the direction of sound.
I have attached an image of a dog's ear to show you the external structure called the Pinna.
I hope this helps! I'm happy to answer any other questions you might have :)
[Image sourced from: https://www.msdvetmanual.com/dog-owners/ear-disorders-of-dogs/ear-structure-and-function-in-dogs]
Earth's atmosphere helps maintain a constant temperature.
Answer:
When the Cheetah starts running, it generates its energy initially by aerobic respiration, where glucose is oxidised in the presence of oxygen, resulting in generation of ATP