Genetic Makeup

I have always been fascinated with the DNA of everything. More in clinical ways than theoretical or scientifical. How can I explain it… I want to know the hows and whys of a living organism without spending hours, weeks, years in a laboratory or drowning myself in paperwork. I want to understand why things behave in certain ways. For example, why cacti (and succulents for that matter) know what shape to evolve and what kind of spines, glochids, spinose teeth or whatever they call it to grow to protect themselves. Why they flower when one abuses and neglects them? Why siblings who grew up in the same environment, shared the same genetic makeup, identical background, and upbringing become completely two different individuals, opposite in every way. Why two identical plants, planted side by side in the garden grow completely different from each other, one of them big and robust, the other small, thinly and dying. I once dismantled a transistor radio and a watch of my father out of sheer curiosity. I wanted to know how they work, what makes them tick. I am none the wiser of course after that episode. I lack the knowledge and the drive to pursue the interest. I am more artistically inclined than technical though I like to think I am both. Anyway, isn’t it handy if we understand the mechanism of everything so we can treat them accordingly?