Technically speaking, neither. See my post #37, starting at the sentence, "Humans have 23 pairs of chromosomes"...
Chromosomes tend to undergo fission and fusion, but the genetic material doesn't magically "appear" or get "lost", it just gets repackaged.
My "cylinder index" is currently at around 23 counting the 9.8hp Merc. that needs a tune-up to run. thanks for asking. shalom