Natural cloning occurs when animals produce genetically identical offspring using asexual reproduction.

Some invertebrates undergo regeneration or fragmentation to form new, genetically identical offspring from parts of their bodies that have broken off.

Invertebrates like Hydra form 'buds' that break off the parent organism and grow into new, genetically identical offspring.

A common form of natural cloning in vertebrates like humans is the formation of monozygotic twins, where an early embryo splits to form two genetically identical embryos.

Artificial embryo twinning is a process in which a single early embryo is manually split to produce multiple identical offspring.

1. A somatic cell nucleus is removed from an adult animal.
2. An ovum of a different female animal of the same species is enucleated.
3. The nucleus from the somatic cell is transferred into the enucleated ovum.
4. The somatic nucleus is fused with the enucleated ovum, often stimulated by electrofusion.
5. The fused cell begins dividing, forming an embryo.
6. This embryo is implanted into the uterus of a surrogate mother.
7. The surrogate eventually gives birth to a clone of the somatic cell donor.

1. A female organism is treated with hormones to produce multiple ova.
2. The ova are extracted and fertilised in a Petri dish by semen to produce an embryo.
3. The embryo divides into several cells and, while the cells are still totipotent, the embryo is split.
4. Each cell is placed into its own Petri dish to develop into individual embryos.
5. The embryos are implanted into the uteruses of surrogate mothers for development.

1. High cost and technically complex.
2. Reduces genetic diversity and increases disease risk.
3. Cloned animals often have shortened lifespans.
4. Some individuals have ethical concerns regarding the destruction of embryos.
5. Cloned animals often have health issues.
6. SCNT is inefficient, as it takes many ova to produce a single cloned offspring due to high failure rates.

1. Medical research - produces genetically identical animals for drug testing and disease modelling.
2. Conservation - offers a method to boost the numbers of endangered species.
3. Agriculture - can replicate animals with desirable characteristics for selective breeding.
4. Pharming - genetically engineered animal clones can be used to produce therapeutic proteins.
5. Stem cells - cloned embryos provide a source of immunocompatible stem cells for tissue repair.

SCNT is a process in which a nucleus is transferred from a somatic (body) cell of one animal into an ovum (egg cell) of another animal to form an embryo.