Xueba, I beg you to go and escort him quickly!

Xu Heng, "Pretend! Just pretend!"

Everyone was helpless, "No! It's really insomnia!"

Xu Heng, "???"

Everyone, "Yang Kaixuan told us that you don't even have to take the final exam. I'm envious..."

While being envious, he was also greatly insulted.

Xu Heng, "Uh..."

This big mouth!

Just as I was about to find Yang Kaixuan, he had already slipped away.

Xu Heng, "%￥#￥..."

never mind!

But this matter will be known sooner or later, so let's talk about it.

In the past, I didn't wash up with Xu Heng, and I didn't go to class together. The roommates haven't noticed anything yet.

But today, they set off with Xu Heng, and when Xu Heng returned to class, they also returned to class.

Xu Heng, "You don't eat breakfast?"

They, "Didn't you eat it too?"

Xu Heng, "I have someone to take it with me."

When I arrive at class, a hot breakfast is such a luxury in winter.

Yue Pingting brought breakfast for Xu Heng.

I can see the envy of the roommates one by one.

"Hey... I can't compare with learning, and I can't compare with popularity..."

"Hey... I can only eat dog food!"

Full of negative energy!

Yang Kaixuan kept his head down, doing his own questions.

My hands are red from the cold and shaking!

As for Xu Heng...

Yue Pingting carefully prepared a teacup for Xu Heng.

"Here you are! There's boiling water inside, you cover your hands."

"Also, don't sleep in class in the future, it's too cold."

Xu Heng smiled, "Then swipe your phone..."

Look at this pair!

Proper dog food!

Yue Pingting, "Xu Heng, actually, can you go home now?"

Xu Heng, "Almost!"

Yue Pingting suddenly laughed, her pretty face flushed.

Xu Heng probably guessed why Yue Pingting did this.

Because from Yue Pingting's point of view, since Xu Heng doesn't even have to take exams, why does he still stay at school?Not for herself, she really couldn't think of any reason.

Invisibly, Yue Pingting was warmed up, and she was doubly nice to Xu Heng...

Still in class!

The teachers are still teaching!

Xu Heng swipes his phone...

Short videos, games, dramas...

Really boring.

Go play ball?

It seems that no one can fight with him.

Going to play, can only be completely crushed.

"Hey……"

Brush questions?

Even more impossible!

finally……

Xu Heng locked his target on Yue Pingting.

Since I don't have to take the exam, but she will.

In less than a week, Xu Heng decided to let Yue Pingting improve.

"I'll find some problems for you to do."

Yue Pingting, "Good!"

But after searching and searching, Xu Heng realized that something was wrong.

"Ah...it seems to be out of class...how did you find the microbiology experiment..."

Hurry up and start over from the beginning, in my mouth, I keep talking about the problem of finding high school.

But no matter how hard I searched, I couldn't find the topic I wanted.

Forget it...

Let's go out by ourselves.

Xu Heng found A4 paper, and directly wrote the questions on it.

1 Which of the following statements about inorganic compounds in cells is correct:

A. Free water is the medium of biochemical reactions and does not directly participate in biochemical reactions

B. Bound water is an important component of cell structure and mainly exists in vacuoles

C. Inorganic salts participate in maintaining the acid-base balance of cells, and do not participate in the synthesis of organic matter

D. Inorganic salts mostly exist in the form of ions, which play an important role in maintaining life activities

2 Which of the following statements about biological macromolecules in cells is wrong...

……

Xu Heng's questions are well-proportioned, and he has all given questions in the Olympiad competition. For him, this question is a piece of cake.

In other words, it is simply overkill.

Yue Pingting saw that Xu Heng was writing the topic.

she,"???"

"Xu Heng, why are you copying the title?"

Just after she finished speaking, she noticed that the phone next to Xu Heng was locked, and Xu Heng didn't look at the phone at all!

Oh my god!

Yue Pingting was surprised, seeing that Xu Heng was concentrating on writing the title.

"Xu Heng, have you memorized all the questions?"

"No! Are you making a question?"

Recite the title?

Even Yue Pingting thought it was stupid, so there was only one possibility left, Xu Heng was posing a question to Yue Pingting!

The kind that comes with a pen!

Yue Pingting's scalp was numb.

"It turns out that you always come up with problems like this! Did you do the same thing in the Mathematical Olympiad competition?"

· · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·??????????????

Xu Heng, "Ah... no, that time was much more difficult than this..."

But Yue Pingting couldn't believe it...

"Wait a minute! I thought you would give me physics or mathematics, or even Chinese, but you gave me biology...err..."

"Xu Heng, don't tell me, your biology is also... strong?!"

Yue Pingting has always believed that Xu Heng has perfect marks in some subjects, that's all. It is definitely not like Chinese, mathematics and physics, but now it seems that she underestimated Xu Heng too much.

Xu Heng continued to ask questions.

He intends to produce a complete test paper.

Yue Pingting, "Xu Heng, I'm also brushing up the biology questions, can you help me take a look?"

topic:

The hair color of Duroc pigs is controlled by two pairs of alleles inherited independently. There are three types of hair colors: red hair, brown hair and white hair. The corresponding gene composition is as follows.please answer the following question:

Coat color: red hair, mane, white hair

Genetic composition: A_B_, A_bb, aaB_, aabb

How many genotypes are there in brown haired pigs?

The F1 obtained by crossing two homozygous brown-haired pigs all has red hair, and F1 is mated with male and female to produce F2.

What are the genotypes of the parents in this cross experiment? F1 test cross, what is the phenotype and corresponding proportion of offspring? Homozygous individuals in F2 cross each other, how many genotype combinations can produce brown-haired offspring (regardless of reciprocal crossing)? What is the proportion of homozygotes in F2 brown-haired individuals? Brown-haired individuals in F2 mate with each other, what is the proportion of offspring white-haired individuals?

If there is a pair of genes I, i on another pair of chromosomes, the I gene has an inhibitory effect on the expression of the A and B genes, and the i gene does not inhibit, and shows white hair as I_A_B_.When individuals with genotype IiAaBb mate with males and females, what is the proportion of red-haired individuals in the offspring?What is the proportion of white-haired individuals?

0 . . . . .

Xu Heng raised his eyebrows slightly, and finished reading the question.

Yue Pingting, "This kind of question is too troublesome."

Xu Heng, "Pig coat color is controlled by two pairs of alleles inherited independently, so it can be seen that the inheritance of pig coat color follows the law of free assortment."

Yue Pingting frowned, "And then?"

Xu Heng gave me a blank look, "Then? Then...you give me a conclusion yourself? Pay attention to the topic."

Yue Pingting pouted her lips, "Oh..."

After tossing for several minutes, Yue Pingting was confused and muttered, "AaBb individuals mate with each other, and the offspring A_B_:A_bb:aaB_:aabb=9:3:3:1?"

Xu Heng continued to come up with his own questions, but he followed Yue Pingting's thinking and said, "That's right, this question mainly examines the application of the law of free combination and the application of the 9:3:3:1 variant."

"So, you should do it first. If it's right, I won't tell you. If it's wrong, I'll correct it for you."

Yue Pingting looked at Xu Heng, her beautiful eyes widened, she was using two things at once!

Xu Heng glanced at Yue Pingting, "?"

Yue Pingting immediately answered the question. She bit the bullet and did some calculations before giving the answer.

Xu Heng looked at it, "The front is not bad, as for the back..."

"It's all wrong here, here, here."

“我和你说，F2的基因型及比例为A_B_：A_bb：aaB_：aabb＝9：3：3：1，棕毛猪A_bb：aaB_

所占比例为6/16，其中纯合子为AAbb、aaBB，所占比例为2/16，故F2的棕毛个体中纯合体所占的比例为2/6，也就是1/3。”

"The brown-haired individuals mate with each other, and the hybrid combination and probability of producing white-haired individuals (aabb) are..."

"Finally, do the math, how much is it?"

Yue Pingting decided according to what Xu Heng said, and said, "1/9?"