Question

A haploid organism produces gametes by mitosis. Does it mean that meiosis never occur...

Answer 1

haploid organisms are mainly prokaryotes like bacteria or archaebacteria

these organisms mostly reproduces by asexual methods like binary fission

so it reproduces mostly through amitosis or mitosis.

meiosis mainly happens in the living organism where sexual reproduction occurs

but there are rare cases where bacteria do meiosis during horizontal gene transfer ie a sexual reproduction in bacterias