I am now reading this book: "The Human Body" by Derek Hall.

The introduction states: The human body can be thought of as a complicated living machine.  It needs energy in the form of food to make it work, it has its own in-built monitoring systems, and it can usually be repaired when it fails.  The result of millions of years of gradual modification and improvement, the human body is versatile and adaptable and is capable of performing remarkable physical and mental feats.

I am now 75 years old and I find that I have a lot to learn - and there are many gaps in my knowledge.  To know how my body works should be very interesting.  What a revelation.  Its fascinating, fantastic even.  I am excited when reading this book.  Yes, life is an adventure!