Greetings, Mister Principal

Chapter 166: laws of inheritance

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In the greenhouse, the vigorously growing peas had a little dew on them. The morning fog had not yet dissipated. Reiner and several students had already arrived here to check on the condition of the third generation of peas.

They first came to field No. 7, which was larger than the others. Densely packed peas were growing in the field, thriving.

"ah... "

The first time she saw this field, Dana let out a small exclamation.

“Sure enough, there are both tall peas and short peas.”

Xia Luo nodded. In the field in front of her, the seeds of tall-stemmed peas were all planted, but they had two completely different traits.

"Traits that did not appear in the previous generation have appeared in this generation. In this way, the bloodline factors are not fused or assimilated, but exist at the same time."

Fina said to herself, the experimental phenomenon in front of her clearly verified the previous hypothesis. The different blood factors inherited from the parents' generation were clearly displayed in the next generation.

"In this way, the blood factor of tall stems is indeed more powerful than that of short stems. If the two blood factors are combined, the pea will show a stronger trait, but the weak blood factor will not disappear because of this. If it continues to be inherited If this continues, the weak blood factor may reappear."

Xia Luo concluded with enlightenment.

"We might as well count the number of tall pea plants and short pea plants in this field, maybe we can get further information."

Reiner didn't say it directly, but reminded him in this way.

"That makes sense."

Fina nodded and said nothing more. Instead, she walked to one side and started counting.

The three of them spread out and counted the plant types in an area. In less than half an hour, they gathered them together.

"The number of tall pea plants was one hundred and sixty-seven, and the number of short pea plants was fifty-six... The number of tall peas was significantly higher."

Dana looked at the record on the paper and said softly.

"The ratio of these two types is close to three to one, and there seems to be some pattern... "

Fina said calmly, but calculations had already begun in her mind.

She subconsciously put her fingers on her lips and thought, her rimless glasses reflecting the ambiguous sunlight that had passed through the greenhouse dome. Then, as if she had a sudden realization, Fina hurried back to the table and started writing with a pen.

"If we assume that the blood factor of tall peas is A and that of dwarf peas is a, then purebred tall peas should be AA. Similarly, purebred dwarf peas should be aa. The second generation of the cross between the two Pea is Aa."

She uses ancient runes to represent explicit and implicit blood factors.

"According to the results of the experiment, as long as there is blood factor A in peas, they will definitely show the characteristics of tall stems. There is no difference in appearance between AA and Aa. Only aa type peas will show short stems." Stem Characteristics.”

"In this case, the second-generation Aa type peas self-pollinate to obtain the third-generation blood factor type, uh, according to the permutation and combination..."

Dana also wanted to do her best to express herself, but she was stuck in calculations.

"AA, two types of Aa, aa, four arrangements, the final ratio of traits is exactly three to one."

Xia Luo quickly answered this question for Xia Luo.

"So, back to the topic we originally wanted to discuss, traits that did not appear in the parents' generation may appear in the offspring, and traits that exist in the parents' generation may not exist in the offspring. The current experimental results are completely This conjecture can be demonstrated.”

Reiner smiled and concluded that he had already got the answer when he saw the condition of the plants in the field. At this time, he just repeated it in a language that the students could understand.

"What we can now understand is that blood factors control the external performance of species. Blood factors exist in pairs, with dominant and recessive distinctions. When both blood factors are present, the species will show dominant characteristics. , at the same time, when the bloodline factors are passed on to the next generation, the combinations will be randomly and freely assigned, so that it can be used to separate dominant and recessive bloodline factors."

The short-stemmed peas that appeared in this field are actually pure aa type. The tall-stemmed peas can also be screened to obtain pure varieties after the next planting. This method will not derive other traits compared to past breeding. The purebred's methods are much more sophisticated and faster.

You must know that breeding purebreds, especially dominant purebreds, without any theoretical support takes a long time and is very inefficient.

"Let's take a look at the situation in field No. 8."

Reiner added that Field No. 8 also had high-stem peas and short-stem peas, but in addition, Reiner also performed another treatment on the peas in this field. The peas here had both smooth surfaces. , also has wrinkled surfaces.

"Here is the third generation of the second-generation peas I obtained by crossing peas with smooth surfaces on tall stems and peas with wrinkled surfaces on short stems, and then self-crossing them. All the second-generation peas have smooth surfaces on tall stems. Apply the previous Theoretically, smooth surfaces are dominant blood factors relative to wrinkled surfaces.”

Reiner asked three students to count the status of the plants in the field. This time, because they needed to check the status of the pea grains, it took longer. It took a full hour and a half before they got the final results.

"One hundred and ninety-two pea plants with tall stems with smooth surfaces, 63 plants with tall stems with wrinkled surfaces, 64 plants with short stems with smooth surfaces, and 22 plants with short stems with wrinkled surfaces... Four traits The ratio of peas is close to 9:3:3:1... "

Xia Luo calculated, and the three of them quickly began to calculate on paper, trying to analyze the cause of this phenomenon.

After about ten minutes, Fina got the answer first.

"When these plants are classified, the ratio of tall stems to short stems is three to one, and the ratio of smooth surface to wrinkled surface is also three to one. In terms of individual traits, the original separation ratio is still maintained. The current distribution, actual The above is the result of the free combination of the two traits!"

"... This shows that the inheritance of tall stems and short stems, smooth surfaces and wrinkled surfaces are independent of each other and do not affect each other. Pea plants with tall stems and smooth surfaces may appear as peas with short stems and wrinkled surfaces. It’s completely different from the previous generation.”

Xia Luo nodded and continued.

"By analogy, if there are three, four, or more types of traits, similar results may occur. If all the external manifestations of the species are controlled by blood factors, then there will be children and It’s a completely different situation from my parents’ generation!”

This is exactly what happened to Emilia!