Fission, budding and spores: reproducing without a partner

0:00How can a living thing reproduce without a partner?

0:04Reproducing with just one parent, and no partner, is called asexual reproduction.

0:10Here are three common ways: binary fission, budding and spores.

0:16Binary fission means splitting in two. A bacterium, a single cell, does this.

0:23First it copies its DNA, the genetic instructions for the cell.

0:28Then it splits into two identical cells, each with a copy of the DNA.

0:34Some bacteria can divide about every 20 minutes, so in an hour, one cell can become 2, then 4, then 8.

0:44Budding is the second way. This is a hydra, a tiny animal that lives in fresh water.

0:51A small bump called a bud grows on the side of the parent, then grows tentacles.

0:58Then the bud breaks off, and the offspring lives on its own.

1:03Spores are the third way. Bread mould is a fungus that grows round spore cases on thin stalks.

1:10The cases burst and release thousands of spores, tiny cells carried by the air.

1:17Each spore that lands on damp food can grow into a new mould.

1:22In all three, the offspring have the same DNA as the parent, apart from rare copying mistakes. They are genetic copies.

1:31And this is not only for microbes: the hydra is an animal.

1:36Binary fission, budding and spores: three ways one parent can reproduce with no partner.