The silkworm sheds its skin, fourth grade composition

This semester, the science teacher gave each of our classmates a pack of silkworm eggs and asked everyone to raise and observe silkworms. My silkworms broke out of their shells very quickly, because my parents and I fed the ant silkworms well every time with bright green and delicious mulberry leaves, so my silkworm babies grew very fast.

One night, I got up to drink water and see how the silkworms were doing. I found that all the other silkworms were eating mulberry leaves. Only one silkworm had a black head and was lying motionless on a mulberry leaf with its head held high. I thought that this silkworm might not adapt to the environment here. Almost dead. When I got up the next morning, I found that the body of the "dying" silkworm last night was obviously larger than the other silkworms. There was a thin layer of skin around it. It was eating mulberry leaves! It turns out that silkworms really grow up after molting, so how do silkworms molt? I decided to solve this mystery. Every day from now on, I pay close attention to the movements of silkworm babies.

Eight days later, another silkworm baby had a black head and lay motionless on a mulberry leaf with its head held high. When it was about to shed its skin, I gently moved it to the light and observed it carefully. After five minutes, the silkworm's mouthparts were the first to detach, and at the same time a gaping hole opened in the middle of its head. It took the silkworm about 20 minutes to stick its head out of its old skin. Maybe it was too tired, so it rested for about 20 minutes after sticking its head out. After it rested, it dug out the old skin at a very fast speed. This process only took about 1 to 2 minutes. After shedding its skin, the whole silkworm was as white as snow and its body was a little wet. The shed skin is beige, thin, and wrinkled. After a while, the silkworm's mouthparts also fell off. The silkworm that has shed its skin is obviously a circle bigger.

Why do silkworms shed their skin? I searched for relevant information and finally understood the reason.

Silkworms have a strong appetite. They eat mulberry leaves day and night and grow very fast. Molting is because the body has grown and the original skin can no longer wrap its body. A silkworm molts six times in its life. After completing four molts, their body will turn light yellow and the skin will become tighter. It indicates that they will wrap themselves in silk cocoons and metamorphose into pupae in the cocoons.

The process and reasons of silkworm molting are finally understood. It made me realize that there are many things around us worthy of observation and exploration. As long as we observe carefully, think seriously, and study diligently, we can understand them better.