Amazing genes

Keywords: genetics, grade one in primary school

This article applies to: the first grade of primary school.

Composition source:

This essay is about the first grade of primary school. The title is "The Amazing Genetics". Welcome to contribute.

Amazing genes

(1) birthmark

Some people may know that I have a red birthmark on my left arm. What's going on here? Don't worry, listen to me slowly.

According to my mother, the birthmark on my arm is inherited from my grandfather. What is heredity? Heredity refers to the transmission of genes, so that future generations can acquire the characteristics of their parents. Genetics is the study of this phenomenon. At present, it is known that the existing life on the earth is mainly based on DNA. In addition to heredity, the factors that determine biological characteristics are also the environment and the interaction between environment and heredity.

It is because of heredity that this kind of thing will come to me. Interestingly, my birthmark will always grow with me and will always grow. When I was young, my little finger was only a little bigger. Now, the birthmark accounts for one third of my left arm.

More interestingly, this inheritance has not stopped, and my little nephew Xu Mengde has the same thing on his back.

I didn't expect this magical thing to appear again in the fourth generation. I use a simple table to explain:

Length of service in the family/clan

Location of birthmark

grandpa

neck

Grandpa's son

neck

granddaughter

On the left arm

grandchild

Houbeishang

Four generations of ancestors, without exception. This is the magic gene!

(2) A knot in one's foot

My foot looks a little different from others, because there is a prominent pimple in the middle of the outside of my foot, which my father accidentally found.

Although others have them, they are not as big as mine. Although my father's feet are there, I feel almost no, they are flat; But mine is concave, how strange!

When I first discovered it, what did my father think it was? Just ask me if it hurts? Is it comfortable to walk? Did you knock? It doesn't hurt even if I press the big pimple on my foot hard. What's going on here?

It was not until my family returned to grandma's house that I concentrated on seeing grandpa's feet, and the real answer was revealed: it was hereditary!

But this time is different from last time. I use a simple table to explain:

Length of service in the family/clan

Do you have a big pimple on your foot?

grandpa

have

Grandpa's child

not have

Grandson (me)

have

grandchild

not have

Why is this? It turned out that this gene did not appear in grandpa's children, but it appeared again after a generation, just on me.

At this time, I thought: how can I be so unlucky, how can any genetic genes appear in me! But it doesn't matter

Alas! Genetics. It's amazing. There are too many amazing things in this world! As long as you have a pair of eyes that will find out, everything will appear in front of your eyes. Isn't it?