James Morton, runner-up in the BBC's Great British Bake Off show, urged people to become donors as he met a woman whose life was saved by a liver transplant 20 years ago.
Morton, 21, and Hannah MacKereth met in a Glasgow tearoom to promote the "Wee Chat" campaign for the NHS Organ Donor Register in Scotland.
"I just think that it's such an easy thing to do, organ donation. You can sign up very, very quickly and save a huge number of lives by doing it," Morton said.
"It makes absolutely perfect sense. I think it's a great system and everyone should do their bit to support it.
"It's a very natural thing not to want to think about your own death.
"It's just something that we ignore for the most part and to bring it into the public eye is just a great thing, to get people to take 30 seconds to sign up online and do something brilliant."
The third-year student doctor has learned a great deal about the transplant process during his studies.
He added: "Whenever we get lectures on transplantation they are some of the most inspiring because you see the true difference it can make.
"We look at case studies and viewing it on an individual basis is so much more powerful than viewing it as a whole load of stats.
"You see people who are in hospital three days a week, their diet is limited they can't really do anything, they are tired all the time, they are off work.
"It's a very low quality of life. Then, after a transplant, they are very near normal, they can achieve anything they want."
Ms MacKereth, of Glasgow, underwent a liver transplant at the age of just seven months and is now preparing to mark 20 years since the operation.
She said: "There was no other option: I had to have the transplant or I would have died.
"So, it was either 'make her comfortable and don't put her on the waiting list' or 'put her on the waiting list and hope that she gets a donor'.
"It's just seven little words: 'I'd like to be an organ donor'.
"I just don't see why you wouldn't want to be one: after all, isn't the gift of life the greatest gift you can give?"
More than 600 people in Scotland are currently waiting for a lifesaving transplant due to a deficit of donors.
The majority of people waiting are in need of a kidney at a total of 514.
Although Scotland has the highest rates of registered donors in the UK at 41% of the population, research by NHS Blood and Transplant has revealed that 96% of people would take an organ if they needed it.
Organs which can be transplanted include kidneys, heart, lungs, liver, pancreas and small bowel.
Tissues such as eyes, heart valves, bone, skin and connective tissue can also be used.
Professor John Forsythe, Scotland's lead clinician for organ donation and transplantation, said: "Due to the generosity of the Scottish people, organ donor numbers are increasing and allowing more life-saving transplants.
"But there is much still to do as people wait on lists for their chance to get a transplant.
"Please think about what you would want to happen to you, add your name to the register and have a wee chat to your family too."
More information about the NHS Organ Donor Register can be found online at www.organdonationscotland.org or by texting WEECHAT to 61611.