Simply put, living things tend to be more ordered than their surroundings. This organization extends through several levels ranging from sub-cellular organelles to cells to whole organisms and even populations of organisms. But wait, so do islands, and stars, and iron bars, and rocks . . . . Ability to reproduce This will be a central theme of parts one and two of this course. Living things as a rule can give rise to relatively similar copies of themselves.
Puppies eventually do grow up into something that usually can.
But wait, stars do too . . . . This is something that will be talked about more in the next course in this series when you look more closely at anatomy and physiology. Amoebae and bacteria will move toward food. Cock roaches move away from light. Children take their hands off hot ovens.