But are they really a good idea? Some scientists say it will soon be possible to connect a sick person’s head to a healthy body.
2030 forecast: human head transplants
Trump card: By 2030, could Donald Trump have extended his lifespan (and the life of his presidency) by transplanting his head onto the body of a much younger American? Glossary
Surgeon - Somebody who carries out operations on unwell people.
Transplants - When a part of one individual's body is given to another in surgery.
Unethical - Not morally right.
Experiments - Tests carried out, often by scientists, to find out whether an idea is true.
China - A country in East Asia, home to 1.4 billion people.
Strict - Harsh and believing that rules must be followed exactly.
Spinal cord - The bundle of nerves enclosed in the spine, connecting parts of the body to the brain.
Patient - Somebody being treated by a doctor.