there could be harmful chemicals
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]
Francis Crick discovered the DNA structure.
All the cells in a person's body have the same DNA and the same genes. However, the difference between cells in different tissues and organs is that the "expression" of the genes differs between cells. ... For example, liver cells have different proteins than skin cells, even though their DNA is the same......this is a google search i hope it helps
Answer;
Because it is cheaper to prevent an illness than to treat an illness
Explanation;
-Health Maintenance Organization(HMO) plans offer a wide range of healthcare services through a network of providers who agree to supply services to members.
-According to HMOs it is better to prevent disease rather than to try to find cures for diseases after they occur, therefore they encourage healthy lifestyle practices.
-Prevention typically consists of methods or activities that seek to reduce or deter specific or predictable problems, protect the current state of well-being, or promote desired outcomes or behaviors.