"Human life is limited, and everyone will get old, sick, and die. But who knows why we get old, sick, and die?"
On the podium, the nearly 70-year-old professor spoke slowly, and his voice echoed through the speakers in the spacious classroom.
"As we all know, the unit of life is a cell. Each of us here is divided from a small fertilized egg cell."
"One becomes two, two becomes four, four becomes eight..."
Under the podium, Chen Chen was leaning on his chin, spinning a gel pen in his right hand, staring at the projection screen in boredom.
"Cells also age and undergo apoptosis. Newly divided cells continue to replace apoptotic cells. This is the secret of our continuous growth."
"However, this division is not infinite."
"In 1965, Professor Hayflick of Stanford University discovered that human cells cannot replicate themselves more than 57 times, and each cell will die after replicating 56 times."
"It's like there is a counter in the cell, which determines when the cell will stop dividing and when the person will age..."
"Theoretically, human cells can divide up to 56 times. Based on the cell division cycle, the maximum life span of a human should be around 120 years old. This theory is called... "
"Crack!"
Just when he was fascinated by it, Chen Chen suddenly slipped his fingers and threw the gel pen away, falling under the table.
Chen Chen immediately bent down and reached out to touch the ground.
"Um?"
Just when his head was lowered below the table, a dark light came into his eyes inadvertently.
Don't ask why light is black. The moment he bent down, Chen Chen did see a black light.
He looked subconsciously.
It was a long strip-like thing, completely black, stuck under the table and embedded in a hidden groove.
So, after Chen Chen picked up the pen, he stretched his arm again and dug at that location.
With a slight exertion, there was a click, and the dark thing was successfully pulled out.
"That classmate over there who is hiding under the table, you answer-"
But at this moment, the professor's voice suddenly came from the podium.
"Pfft!"
There was a burst of low laughter from the best friends in the dormitory behind him.
Chen Chen quickly got out from under the table, his face flushed with embarrassment.
He looked at the professor who was still smiling, then looked down at the textbook, and then he stumbled and said, "H-Haiflik limit?"
"Please take a seat."
The professor pressed his hand and asked Chen Chen to sit down.
The lecture continues.
"At both ends of DNA, there are things called telomeres, which play a crucial role in cell division."
"It is responsible for keeping the chromosomes intact. Each time a cell divides, the telomeres will become shorter. When the telomeres are too short to protect the genetic structure, the cells will inhibit growth, stop replicating, and enter senescence."
"This is the Haiflik limit."
As he spoke, the professor turned around and quickly wrote the words "Haiflik Limit" on the blackboard.
Chen Chen, who sat down again, breathed a sigh of relief. While the professor was turning around to write, he quickly picked up the thing in his hand and took a look.
emmmmm…
This glance made Chen Chen lose all interest.
It turned out that the black thing was nothing but a USB flash drive.
Different from the USB flash drives on the market, this USB flash drive is much longer than ordinary USB flash drives, a full twelve or three centimeters, and looks like a carbon rod.
Only the US interface exposes the fact that it is just a USB flash drive.
In addition, the entire USB flash drive is completely integrated and pitch black, and even the trademark and memory logo do not exist.
However, because of the cool look, Chen Chen finally put the USB flash drive into his trouser pocket and studied it later when he returned to the dormitory.
At this time, the professor continued his lecture: "With the current level of technology, it is impossible for cells to break through the Hayflick limit, but we can also circumvent this problem in other ways..."
As he spoke, the professor wrote five words on the blackboard again:
Eternal Hela.
"Everyone must be thinking, if there was a way to prevent telomeres from fraying, would our cells be immortal?"
"The answer is yes!"
The professor excitedly added the words "HeLa cell line" under "Immortal HeLa".
"The HeLa cell line is a cell line isolated from human cervical cancer tissue in 1951. Its contributor is Henrietta Lacks."
"Researchers found that the cells collected from Lacus not only did not die, but showed signs of growth, with the number of cells doubling every 24 hours."
"It was later discovered that the reason for these cells' immortality lies in the RT tumor virus that causes cervical cancer. The gene of this virus can change the 'switch' of normal cell life span, thereby making cells immortal and multiplying indefinitely."
"In the years that followed, HeLa cells were provided to research institutions across the federation. They helped scientists achieve cell cloning. They were also used to investigate the effects of nuclear radiation on the human body. They were also used on rockets flying into space to study weightlessness. Cell proliferation under conditions… ”
"According to data from medical and biological databases, as of this year, there have been more than 65,000 papers related to HeLa cells, and more than 50 million tons of HeLa cells have been cultured... "
"Thus, there is a common sense that everyone knows in the future - cancer cell lines are 'immortal'. As long as there is a suitable culture environment, they can divide indefinitely."
At this point, many students in the audience began to applaud spontaneously, which was a tribute to the contributor.
"Of course, if we humans use this 'switch', it will be a recipe for death!"
The professor changed the subject and suppressed the applause.
"After all, if the division cycle of cells in our body is disrupted and cannot age on time, it will turn into a malignant tumor and threaten our lives!"
"We humans are constantly advancing on the road of pursuing truth. As early as the clan society period, the average life span of humans was less than 20 years old. By the Middle Ages, the average life span of humans had advanced to 40 years..."
"With the emergence of science, human civilization has completely entered a period of rapid development. In just a few decades, the average life expectancy of people in the Earth Federation has approached 80 years!"
"But is this enough?"
"Even if human beings develop to the extreme, they will only be 120 years old as described by Hayflik's limit, which is far from the level of immortality. So what should we do?"
After a pause, the professor continued.
"So, here comes the turning point..."
"In 2002, this 'switch' was finally found. Cambridge University professor John Sulston and three others discovered a genetic regulation mechanism called 'programmed cell death.'"
The professor once again wrote the words "programmed cell death" on the blackboard and drew a circle.
There was a click, and the chalk suddenly broke because the fingers were too hard.
"This discovery shocked the entire medical community because it determined that cell death is a physiological and active 'suicide', like a program that has been programmed!"
The professor opened his hands and said, "In other words, we think aging is a natural process, but in fact it may be a genetic defect! If we can repair this defect, we can hope to defeat aging and gain immortality!"
The audience suddenly cheered.
As if a brand new door had been opened, Chen Chen's pupils shrank, and he kept repeating those two magical words in a voice that only he could hear.
"eternal life?"
"Eternal life..."
"Therefore, as a major in biological sciences, you are the most promising generation to repair genetic defects."
An expectant smile appeared on the professor's face, "In other words, you are the generation closest to immortality in human history!"
By this time, the course was coming to an end.
The silver-haired professor picked up a handkerchief to wipe his sweat, and concluded with expectation and sigh:
"It has to be said that we humans still know nothing about the vast sea of truth. Perhaps even the unattainable dream of eternal life is just the first step in the pursuit of truth..."
"But no matter what, the future belongs to you..."
"Okay, get out of class is over!"
Bang bang bang bang bang...
The audience immediately burst into warm applause.