"Xiao Zhang, why do you still wear long sleeves on a hot day, can you wear no short-sleeved overalls?" a colleague on the side asked with concern.

"It's okay, I've been a little bit less resistant lately, I catch a cold at every turn, there is air conditioning in the department, I'm comfortable wearing long sleeves" Zhang Qiao smiled shyly, a little embarrassed by such concern.

"Then you have to pay attention, is your body too weak, eat more wolfberry mutton to supplement, how can your body be like this when you are young." Looking at his colleague's serious expression, Zhang Qiao looked embarrassed, "Is it so like kidney deficiency? There are people who make such suggestions at every turn, but there is no harm in supplementing it, I will buy some wolfberries when I go back from work, maybe adding some wolfberries to the blood will have a miraculous effect!" Zhang Qiao began to open his mind again, and he had a crooked idea.

I don't blame my colleagues for being strange, Zhang Qiao is now wearing long clothes and trousers, an autumn white coat on the outside, tightening the cuffs with gloves, wearing a disposable hat on his head, and a mask on his face, like a dress that is about to rush to the front line of infectious diseases. It's the hottest dog day now, and the blazing sun outside is baking the earth, although there is air conditioning in the department, it's no wonder that Zhang Qiao looks like this, and everyone cares about him.

It's so hot. Each air conditioner is turned on to 18 degrees, is adding full horsepower to deliver cool breeze, despite this, everyone still feels hot, on the one hand, the glass is not completely sealed, and there is air communication outside, on the other hand, the department is full of all kinds of instruments, the heat emitted can not be underestimated, everyone is wearing short sleeves, there is a little fat and afraid of heat, already covered in sweat, on the other hand, Zhang Qiao, the bag is tight, there is no sweat on the body.

Zhang Qiao, who bows his head and does things, doesn't care about the evaluation of his colleagues about nothingness, he is immersed in his own spiritual world, since the last time he found out that he has a bloodthirsty impulse, Zhang Qiao will find "nutritious" blood every day to meet his requirements, generally drink about 30ML of blood in the early morning every day, when the seven-day cycle, this number should be multiplied by three, in the laboratory, a resource-rich place, Zhang Qiao is not worried about no food, and even he can pick and choose, choose the most suitable target.

The only thing that made him dissatisfied was that after drinking so much blood, his body not only did not turn for the better, but his skin became more and more pale, and the color of his blood vessels became more and more purple and black, especially on his feet, which had reached the point where people felt abnormal at a glance, so Zhang Qiao usually covered his skin with various things, trying not to make people suspicious, on such a hot day, he was also fully armed, blocking those parts that he didn't want people to see.

Back in the dormitory after work, Zhang Qiao likes to watch the changes in his skin, although pale but elastic, especially increased toughness, last time I didn't believe that the needle pierced the glove, but it didn't puncture the skin, which made Zhang Qiao have a new understanding of the hardness of his skin.

Looking at his pale skin, Zhang Qiao remembered Yuan Mei's description of zombies in "Zi Buyu" in the Qing Dynasty, which has a detailed division of zombies: the corpse shortly after death has a lilac body due to the lack of blood circulation, which is the incomplete form of the zombie and even unable to move freely, which is called purple zombie.

With the passage of time, the yin qi enters the body, and the corpse slowly turns white, and the zombies at this time are very easy to deal with, slow to move, afraid of light, afraid of fire, afraid of water, afraid of chickens, afraid of dogs, and even afraid of people, called white zombies.

Later, the corpse qi emitted by the corpse combined with the power of Taiyin, changing into green, compared with the white zombie, the green zombie jumped extremely fast, not afraid of people, not afraid of domestic animals. The only weakness is the fear of the sun.

In the end, after cultivation, the corpse developed again, growing a body of hair, copper skin and iron bones, agile movement, flying eaves and walls, jumping like flying, not afraid of fire, not afraid of sunlight.

As for the thousands of years of practice mentioned later, the flying stiffness that can use spells to fly to the sky and the earth, and even the countries that walk like the wind, the countries that you see are all in drought, and the drought that comes out and is thousands of miles away, and even the demon god-like skull, Zhang Qiao thinks that this is the fantasy of a novelist, how many years of history of world civilization, and practice for thousands of years at every turn, thousands of years ago the ancients were rowing wooden boats, and now there are aircraft carriers.

If there really was a zombie, Zhang Qiao believes that this must be a strange species that is different from humans, and ancient books always describe that a living person is bitten by a zombie and becomes a zombie after being poisoned, or the geographical location of the special feng shui buried by the resentment has not disappeared and becomes a zombie.

This characteristic is very similar to a virus, which exists in a special environment and can be transmitted through blood. But what kind of people become zombies? Are there any specific rules for the conditions for producing zombies? Who is buried in that giant coffin, is it a zombie? There are no answers to these questions, and Zhang Qiao feels that his head is big.

"What is a zombie virus that can exist with the body of a normal person, after death, through special conditions to make it a new species, and can spread through blood infection. Zhang Qiao thought distressedly, "Symbiosis, coexistence, contagion, transformation, what is it?" Zhang Qiao thought in a divine way, and suddenly a flash of inspiration flashed, like a lightning bolt across the fog of thinking, Zhang Qiao thought of a possibility.

In junior high school biology, it is said that the role of mitochondria in cells is very important, absorbing nutrients and oxygen, carrying out aerobic oxidation, and providing a lot of energy for cell activities.

It can be said that without mitochondria and chloroplasts, there will be no survival of plants, no plants to produce nutrients and oxygen, and there will be no animal activities, then the world will still be a chaotic prehistory, the only single-celled organisms struggle to survive, lose the mitochondria to provide energy, we will degenerate to the era of prokaryotic cells, how can there be such a colorful and beautiful world where all things grow today, and it is impossible to appear the primate of all things - human beings.

The study of mitochondria and chloroplasts has always been valued by the majority of scientists, and when analyzing their genetic material, scientists have found a peculiar phenomenon: mitochondria and chloroplasts have relatively independent DNA and its transcription and translation systems, indicating that they and other components in the cell are not the same source.

Hundreds of millions of years ago, prokaryotic cells engulfed each other, large prokaryotic cells engulfed small prokaryotic cells without digestion, small cells gradually transformed into mitochondria and chloroplasts, and large cells gave up their own respiratory and photosynthetic systems to form symbionts, they cooperated with each other, improved efficiency, and finally won evolution, and let their genes continue to this day. This is the theory of endosymbiosis.