Several questions

> 3. I was told that the more introns that you have, the greater your

Your other questions were answered.

I think you're confusing introns with telomeres here. There's not really a
direct connection between telomere length and lifespan, but it works like
this:

Telomeres are repetetive sequences at the end of chromosomes. When a
chromosome is replicated, the ends get lost, so the telomeres act as a sort
of buffer of losable material.

When you run out of telomeres, your DNA will start missing vital stuff,
eventually, and then you'll die from a lack of one or more vital proteins.
This is a problem with animal clones. The cloned DNA has whatever telomere
length the parent had, whereas an ovum fertilized from a sperm gets its own
brand new set of telomeres.

I don't think this is a normal cause of death in people. I think organs
usually give out, or disease develops, before your run out of telomeres, but
I could be wrong.