Academician Liu's class is naturally unabsence.

Students who are able to pursue a doctorate degree at the Institute of Zoology of the Chinese Academy of Sciences have an extraordinary thirst for knowledge.

I can't wait for Academician Liu to instill all the knowledge in his brain into them at once, even if he can't digest it immediately, he can listen to it.

Liu Wei dressed like an ordinary student.

Younger in age.

However, after a long time of survival and experience in the wild, his originally handsome face was smeared with a layer of mature man's taste.

Therefore, it seems that it is no different from the doctoral students in the large classroom.

He found a place in the back row and sat down in the aisle.

Academician Liu approached the classroom with his thermos cup, took two sips, and put it on the lectern.

The assistant begins commissioning the mobile teaching equipment.

After the debugging was completed, the assistant nodded to Academician Liu and sat down in the first row by the door.

The classrooms are kept quiet.

It is completely different from the classroom of primary and secondary school students, even if the class has not yet started, there are some problems discussed between the classmates, and the voice is lowered very low, for fear of affecting other students, after all, the people who can sit in this classroom are not much worse than whom!

Liu Wei suddenly felt out of place.

Academician Liu walked up to the stage, landed his right hand on the lid of the thermos cup, and snorted twice to moisten his throat.

The class suddenly entered an atmosphere of curiosity.

All eyes were on the podium.

Academician Liu smiled, "Students, the topic we are discussing today is the excitability of biology, this topic is a commonplace animal physiology topic, and it is also the most basic feature, before starting the formal class, I will show some videos to the students!"

Academician Liu stared at the computer on the podium and clicked play.

The projector projects the video onto the wall around it.

The video being played was edited from the video recorded by Liu Wei's live broadcast.

I have to say that Academician Liu's assistant is a very good editor, who closely grasps the theme of "excitability", and puts the beast in panic, fighting, and mating...... And so on and other exciting video clips came out to make a collection.

Liu Wei himself watched it with enthusiasm.

Compared to the rest of the class, their thinking is more inclined to the reaction of the animal behind the hot blood video.

However, even the most rational person has to pay attention to the other protagonist in the video while watching the video, that is, Liu Wei.

The girl sitting next to Liu Wei, wearing retro round-framed eyes, pushed the glasses frame on the bridge of her nose, looked at the video, and then turned her head to look at Liu Wei.

It seems to be the same person!

She reached out and patted Liu Wei's arm, Liu Wei looked back at her, and she asked, "Classmate, is that person in the video you?"

Liu Wei nodded, "Is there any problem?"

"No, no!" She waved her hand.

Then the students in front and back all looked at Liu Wei and looked at the inconspicuous corner in the back row.

As more and more people look backwards.

This originally quiet classroom gradually became noisy.

Someone recognized Liu Wei sitting in the back row at a glance, "It's really him! I've watched his live broadcast!"

"There is a buddy in our dormitory who watches every day and is fascinated!"

"It is said that he seems to be a student of Academician Liu, a representative of the young generation of animal research practice in China!"

Academician Liu stood on the right side of the classroom, leaning against the window, and his eyes followed the students' eyes to Liu Wei.

Liu Wei kept a smile on his face.

In his heart, he actually hopes that it is a live broadcast now, so he can preach more casually: "Ji Cao, Ji Cao!"

However, it is now in the classroom of a doctoral student at the Institute of Zoology of the Chinese Academy of Sciences.

The atmosphere is completely different.

At least there are no words like ",,, ......," in class.

The video is 15 minutes long.

After the release.

Academician Liu walked up to the podium to close the video, and said with a smile: "When watching the video, the eyes of the students are all looking behind in unison, you should have noticed that the person with the wild ** stream in the video is my student Liu Wei, who is now sitting in the corner on the right."

Before I came to class today, I decided on the topic of discussion in class, and biological excitability covers a wide range of topics.

Broadly understood, the ability of the body to respond when it is stimulated by changes in its surroundings is called excitability.

A change in the environment that causes the body or its tissue cells to react is called a stimulus. The stimulus causes metabolic changes in the cells of the body or its tissues and changes in their activity, which is called a response.

There are two types of reactions: one is from relatively stationary to active, or from weak to strong, which is called excitation.

The other is the change from activity to relative rest, or from strong to weak activity, which is called inhibition.

Whether the response to a stimulus is excitable or inhibited depends on the quality and quantity of the stimulus and the functional state of the body at the time.

In the video that has just been played, the excitement generated by the beast is that there is a relatively static state that becomes an active state, and then Liu Wei uses his experience and professional knowledge to try to change the cognitive environment of the beast, and then makes the active state become a relatively static state, which is inhibition.

We can see that before and after contact, the quality and quantity of the stimulus are balanced, and the body, that is, the beast in the video, switches between the two states.

That's how it works, and before we dive in, I'd like to ask Liu Wei to come up and share with you his understanding of biological excitability!"

Academician Liu took the initiative to clap his hands twice.

The students clapped their hands.

Liu Wei breathed a sigh of relief, found the state of the live broadcast, raised his spirits, and thought about it on the other hand, in fact, he was not so nervous, just treat it as a live broadcast.

He walked up to the stage and said with a smile: "Hello brothers and sisters, it is an honor to come to Mr. Liu's discussion class today.

Relatively speaking, my academic research direction is different from yours, with a bias towards biological evolution, and your academic research biased towards applied science. ”

Looking back at the topic on the screen, he said: "Just now Mr. Liu interpreted excitability in a broad sense, and I will now take you to understand it in a narrow sense, excitability refers to the ability or characteristic of excitatory tissues or cells to react when they are stimulated.

Excitable tissues refer to tissues (or cells) that can produce action potentials when stimulated, and are called excitable tissues (or cells), usually referring to nerves, muscles, and glandular cells.

In fact, almost all living tissues or cells have some degree of ability to respond to external stimuli, but the sensitivity and the form of the response are different.

In various animal tissues, in general nerve cells, muscle cells and glandular cells show high excitability, and in the video just now, the aggression of the crocodile in the face of me is mainly the excitability shown by muscle cells, which we usually call the instinctive response of animals.

And the mating behavior of the elephant in the video is the excitability shown by glandular cells.

In addition, cardiomyocytes are excitatory like nerve cells, and the cyclical changes in excitability are similar to those of nerve cells.

When cardiomyocytes are stimulated to produce an excitation, a series of periodic changes occur in the excitability, which are closely related to the changes in membrane potential and channel function.

......”

Liu Wei's mouth was like a river, and he couldn't stop at all.