Question

how do bread mould multiply

Answer 1

They grow from tiny spores that float around in the air. When some of these spores fall onto a piece of damp food or other materials, they grow into molds. ... The molds that grow in your mold terrarium feed on the bread, cheese, and other foods. A mold produces chemicals that make the food break down and start to rot.

Answer 2

Bread mould multiply by the process of budding.