Questions? "The House of the Scorpion"

I have many questions lingering in my head at this point. The main one being what is Matts purpose of being a clone? I believe its to fill El Patrons shoes because he is the clone of El Patron but the book is giving me no evidence to support that. Also why is El Patron 145 years old but no one else in the book lives to be that long? Yeah i get that they have many scientific achievements than we have right now but why is he the only one living that long? My next question is why is everyone so afraid of El Patron? He is a scrawny old man and is in a wheelchair, what could be so scary? A part answer is he is rich and probably has paid gunman watching every single person but I want to know what is so scary about him. My last question is why does Matt belong to the Alacran family as a clone when the family absolutely hates his guts. Why would they spend time and money on this clone and hate him so much? Hopefully I will answer some of these questions as I read farther into the book.