Because it is flexible. Think about it; the ribs protect both the lungs and the heart. If the ribs were solid bone all the way around then unless you constantly break your ribs you wouldn't be able to expand the cheat to breath. Additionally your lungs would constrict the heart to a degree that it would function properly.
It should be discretionary calories. im sorry if i'm wrong!
That looks like Pseudostratified Columnar. Could be wrong but I'm 95% certain.
Hope this helps
Answer:
Generally, answer B would be the right one.
Explanation:
[source;https://www.healthline.com/health/eating-disorders-causes-risk-factors]
"The exact cause of eating disorders is unknown. However, many doctors believe that a combination of genetic, physical, social, and psychological factors may contribute to the development of an eating disorder.
For instance, researchTrusted Source suggests that serotoninTrusted Source may influence eating behaviors. Serotonin is a naturally-occurring brain chemical that regulates mood, learning, and sleep, as well as other functions.
Societal pressure can also contribute to eating disorders. Success and personal worth are often equated with physical beauty and a slim physique, especially in Western culture. The desire to succeed or feel accepted may fuel behaviors associated with eating disorders,"
Blocked, and the heart can't get oxygen.