CATDOLL : CATDOLL: What are the main stages of silkworm rearing?

1. What are the four stages a silkworm goes through in its life?

The silkworm's life cycle consists of four stages: egg, larva, pupa, and adult. Silkworms eat a lot of mulberry, so they grow very fast and their body color gradually fades.

But its appetite gradually decreases and it even stops eating completely. It spits out a small amount of silk, fixes its abdominal feet on the silkworm seat, raises its head and chest, and stops moving, as if it is asleep. This is called "sleeping".

2. What are the four main stages in a silkworm’s life?

The silkworm has four developmental stages in its life: egg, larva, pupa and moth. May 1st, sunny. We bought a one-year-old silkworm. When we first saw it, we were shocked. It was black all over and very small.

3. What are the differences in morphology and behavior during the four major stages of a silkworm’s life?

It mainly goes through the following four stages: silkworm eggs, silkworm ants, silkworm pupae, and silkworm moths.

1. Silkworm eggs: Silkworms reproduce by eggs. Silkworm eggs look like fine sesame seeds, about 1 mm wide and 0.5 mm thick. The outer layer of silkworm eggs is a hard eggshell, and the inside is yolk and serosal membrane. The embryo in the fertilized egg continuously absorbs nutrients during the development process and gradually develops into a silkworm.

2. Ant silkworm: When the silkworm hatches from the egg, its body color is brown or black. It is extremely small and has many fine hairs. It looks a bit like an ant, so it is called ant silkworm.

3. Silkworm pupa: After about 4 days of cocooning, the silkworm will turn into a pupa. The body of the silkworm pupa is like a spindle, with three body sections: head, chest and abdomen. When the silkworm first turns into a pupa, its body color is light yellow, and the pupa body is tender and soft, and gradually turns into yellow, tan or brown.

4. Silkworm moth (adult): Silkworm moths are shaped like butterflies, with white scales all over their bodies, but because of their small wings, they have lost the ability to fly. Extended information: Silkworms have a strong appetite. They eat mulberry leaves day and night, so they grow very fast, commonly known as silkworms swallowing whales. There are suction cups on their feet that can be sucked on rough objects. When the color of their heads turns black, it means that they are about to molt. After completing four molts, their bodies will turn light yellow and their skin will become tighter, indicating that they will wrap themselves in silk cocoons and metamorphose into pupae in the cocoons. If the pupa is allowed to metamorphose into an adult, the cocoon will naturally dissolve and drill out, and the silk thread will become shorter because the cocoon will be broken into holes, and it cannot be used for spinning and weaving silk. Therefore, the cocoons should be put into boiling water before they break out of the cocoon to kill the silkworm pupae and make the cocoons easy to disassemble. The worms and pupae of silkworms can be eaten and have therapeutic effects. Adult moths cannot fly, and they are also called "silkworm moths". They are only used to lay eggs to reproduce offspring. Female silkworms are generally fatter than male silkworms. Because of its long history and economic importance, the genes of silkworms have become an important research object of modern science.

4. What are the four stages of a silkworm’s life?

The life cycle of a silkworm is from egg to larva, and then from larva to pupa.

, and then from the pupa to the adult, these four stages are metamorphosis insects.

Silkworm eggs: Silkworms reproduce by eggs. Silkworm eggs look like fine sesame seeds, about 1 mm wide and 0.5 mm thick. A female moth can lay 400 to 500 silkworm eggs. 1700 to 2000 silkworm eggs weigh about 1 gram and have a diameter of 0.2 cm. The color of silkworm eggs is light yellow or yellow when they are first laid, and changes to light red bean color or red bean color after 1 to 2 days, and then turns to gray-green or purple after 3 to 4 days. It no longer changes and is called a fixed color.

5. What is the sequence of changes during a silkworm’s life?

The life of a silkworm: eggs laid by silkworm moths → hatching → cocoons and pupae → moths, completing the cycle of a new generation. This is the life history of a silkworm.

Silkworm eggs: Silkworm eggs look smaller than sesame seeds, and are round and flat. A female moth can lay 400 to 500 eggs. Silkworm eggs are light yellow when they are first laid, and turn into light red bean or red bean color after 1 to 2 days, and then turn into gray-green or purple after 3 to 4 days, and then they will not change again. Hatching silkworms is a bit like hatching chicks. When we were young, we usually put silkworm eggs in the pockets of our clothes and use our body temperature to accelerate the hatching. We would take them out and have a look when we had nothing to do. Silkworm eggs are like chicken eggs, with a hard shell on the outside, and yolk and serosal membrane inside. The embryo in the fertilized egg continuously absorbs nutrients during the development process, and gradually develops into an ant silkworm, which breaks out of the egg shell.

Ant silkworm: When the silkworm emerges from the eggshell, it is very thin and looks a bit like an ant, so it is called an ant silkworm. The ant silkworm is about 2 mm long and 0.5 mm thick. It will eat mulberry leaves 2 to 3 hours after crawling out of the eggshell.

Silkworm sleep: Silkworms eat a lot of mulberry, and the faster they eat, the faster they grow. When their body color gradually fades and their appetite gradually decreases until they completely fast, they will spit out a small amount of silk, fix their abdominal feet on the silkworm seat, raise their head and chest, and stop moving, as if they are asleep. This is silkworm sleep. The sleeping silkworm may seem motionless on the outside, but it is preparing to shed its skin inside. After shedding the old skin, the silkworm's growth enters a new stage, and it sheds four times from ant silkworm to spinning silk cocoon. Having a dormant nature is one of the growth characteristics of silkworms.

Silkworm age: from the first molt to the first molt is the first age; after waking up from sleep, it enters the second age; after molting again, it enters the third age; after the third molt, it enters the fourth age, and the fourth molt is the long sleep. After the long sleep, it enters the fifth age. The fifth-age silkworms grow very fast. The longest silkworm we raised this time reached 8 cm.

Mature silkworms: When silkworms reach the end of the fifth instar, they gradually show the characteristics of maturity: first, the feces they excrete clearly change from dark green to leaf green; their appetite decreases, and the amount of mulberry food they eat drops significantly; their chest becomes transparent; their bodies turn a little yellow, and then they stop eating completely. Their bodies shorten, and their abdomens tend to be transparent. Their head and chest are raised, they spit out silk threads from their mouths, and they swing left and right and up and down to find a place to build their cocoons. These silkworms are called mature silkworms.

Cocooning: After the silkworms are mature, they are placed in a special container or on a cocooning device, and the silkworms will spin silk and spin cocoons. (The cocooning device is the place for making cocoons. Some branches or chopsticks can be used to make a #-shaped or trident frame.) The process of silkworm cocooning is roughly as follows: the mature silkworms find a good place to make cocoons, first spin out silk, and stick it on the cocooning device to form a cocooning frame, that is, a cocooning net. Continue to spin out messy silk circles to thicken the inner layer of the cocoon net, and then spin silk in an 8-shaped manner, and the outline of the cocoon begins to appear, forming a cocoon coat. After the cocoon coat is formed, the cocoon cavity gradually becomes smaller, and the silk continues to be spun to thicken, which begins the process of forming a cocoon layer. When the silkworm's body is greatly reduced due to spinning a large amount of silk, a loose and soft cocoon silk layer is finally formed, which is called the pupa lining.

Silkworm pupa: About 4 days after the silkworm makes a cocoon, it will turn into a pupa. After about 12 to 15 days, when the pupa body begins to soften again and the pupa skin is a little wrinkled and earthy brown, it will turn into a moth.

Silkworm moth: The silkworm moth that emerges from the cocoon loses its ability to fly because of its two pairs of small wings. The female moth is large and crawls slowly. The male moth is small and crawls faster, with its wings vibrating rapidly, looking for a mate. Generally, after mating for half a day, the female moth can lay fertilized eggs. After mating, the male dies, and the female moth can lay about 500 eggs in one night, and then slowly dies.

6. What are the summary stages of silkworm rearing?

1. Stages of silkworm development

This small animal generally goes through four different stages in its life. These four stages are eggs, which are silkworm eggs, larvae, silkworm pupae, and finally adults, which are what we call silk moths.

2. Growth from larva to pupa

The life of a silkworm is about 50 days, which can be said to be relatively short. However, in these 50 days, the silkworm undergoes great changes every day. The growth process from larvae to pupae is the main part and the most changing. The silkworm needs to go through constant sleep and molting from larvae to mature pupae. First, when the larvae hatch from the eggs, they need to eat leaves for three days, then stop eating and sleep, and when they wake up again, they will molt and become second-instar silkworms. Then, according to this method, the second-instar silkworms will eat leaves for a few days and then molt and sleep again, and then become third-instar silkworms. The third-instar silkworms also need to take in a lot of food, and eventually become fourth-instar silkworms. When the fifth-instar silkworms mature, their bodies will become translucent, and at this time they will spin silk and become silkworm pupae.

7. What are the four stages of a silkworm’s life?

The first stage is hatching. The silkworm eggs are similar in appearance to white sesame seeds. As they slowly change, the silkworm babies will emerge from the eggshells, resembling small ants and are called mosquito silkworms.

The second stage is growth. The ant silkworm starts to eat mulberry leaves and slowly turns white. After four moltings, it grows into a larva and is ready to spin silk.

The third stage is cocooning. The silkworm needs two days to spin silk to make a cocoon and then turn into a pupa inside the cocoon.

The fourth stage is the adult. After about ten days, the silkworm breaks out of the cocoon and becomes an adult. It mates in a short period of time, lays sperm and eggs, and then gradually dies.

8. What are the four stages in the life of a silkworm?

The life cycle of a silkworm consists of four stages: egg, larva, pupa and adult.

Silkworm eggs:

Silkworms reproduce by laying eggs. Silkworm eggs look like fine sesame seeds, about 1 mm wide and 0.5 mm thick. A female moth can lay 400 to 500 silkworm eggs. 1700 to 2000 silkworm eggs weigh about 1 gram and have a diameter of 0.2 cm. The color of silkworm eggs is light yellow or yellow when they are first laid, and changes to light red bean color or red bean color after 1 to 2 days, and then turns to gray-green or purple after 3 to 4 days. It no longer changes and is called a fixed color.

The outer layer of the silkworm egg is a hard eggshell, and inside is yolk and serous membrane. The embryo in the fertilized egg continuously absorbs nutrients during the development process and gradually develops into a silkworm. It crawls out of the eggshell, and the eggshell becomes white or light yellow after it is empty.

The first instar is four to five days; the second instar is three to four days; the third instar is four days; the fourth instar is six days; the fifth instar is seven to nine days; the pupal stage is fourteen to eighteen days; and the moth stage is three to five days.

larva:

When the silkworm hatches from the egg, its body is brown or black, very small, and covered with fine hairs, and it looks a bit like an ant, so it is called ant silkworm. The ant silkworm is about 2 mm long and 0.5 mm wide. After it crawls out of the egg shell, it will eat mulberry leaves after 2 to 3 hours.

silkworm chrysalis:

After the silkworms spin cocoons on the cocoon nest, they will turn into pupae after about 4 days. The body shape of the silkworm pupa is like a spindle, with three body sections: head, thorax and abdomen. The head is very small, with compound eyes and antennae; the thorax has thoracic legs and wings; the bulging abdomen has 9 body segments. Professional workers can distinguish the sex of silkworms from the lines and brown dots on the abdomen of the silkworm pupa. When the silkworms first pupate, their body color is light yellow and the pupa body is tender and soft. Gradually, it will turn into yellow, yellow-brown or brown, and the pupa skin will also harden. After about 12 to 15 days, when the pupa body begins to soften again and the pupa skin is a little wrinkled and earthy brown, it will turn into a moth.

9. What are the four main stages in a silkworm’s life?

There are four stages: silkworm egg, silkworm, pupa and silkworm moth.

Silkworm, egg, silkworm pupa and silkworm moth are the four forms that the silkworm will go through in its life. The silkworm goes through four stages in its life: birth, growth and development, reproduction, and death.

Therefore, the answer is: four stages: silkworm egg, silkworm, pupa and silkworm moth.