CATDOLL : CATDOLL: How to write a brief description of the growth process of silkworms (How to write a brief description of the growth process of silkworms)

1. What is the growth process of silkworms?

Silkworms have four stages: egg, larva, cocoon and adult.

Silkworm eggs are transparent in the early stages and black in the later stages. The newly hatched larvae are black and feed on young mulberry leaves. The later larvae turn white and feed on old mulberry leaves. The fifth-instar larvae will spin silk cocoons and break out of the cocoons after ten days to become adults.

1. Silkworm eggs

The first stage of silkworm growth is the silkworm egg. The silkworm egg is round and small in size. The newly laid silkworm egg is transparent. At this time, wrap the silkworm egg in a paper towel. After a period of time, the silkworm egg will turn black and the larvae will hatch.

2. Larvae

The second stage of silkworm growth is larvae. The newly hatched larvae are black and covered with fine hairs. At this time, they need to be provided with fresh mulberry leaves to supplement their nutrition. After a week, the silkworms will turn white and begin to shed their skin. A larvae must shed its skin four times in total before it can grow to maturity.

2. What is the growth process of silkworms?

Silkworms have four stages: egg, larva, cocoon and adult.

Silkworm eggs are transparent in the early stages and black in the later stages. The newly hatched larvae are black and feed on young mulberry leaves. The later larvae turn white and feed on old mulberry leaves. The fifth-instar larvae will spin silk cocoons and break out of the cocoons after ten days to become adults.

1. Silkworm eggs

The first stage of silkworm growth is the silkworm egg. The silkworm egg is round and small in size. The newly laid silkworm egg is transparent. At this time, wrap the silkworm egg in a paper towel. After a period of time, the silkworm egg will turn black and the larvae will hatch.

2. Larvae

The second stage of silkworm growth is larvae. The newly hatched larvae are black and covered with fine hairs. At this time, they need to be provided with fresh mulberry leaves to supplement their nutrition. After a week, the silkworms will turn white and begin to shed their skin. A larvae must shed its skin four times in total before it can grow to maturity.

3. Briefly introduce the growth process of silkworms?

The growth process of silkworms introduces the morphology of silkworm eggs, silkworm pupae, silkworm moths and the growth characteristics of silkworms.

Silkworm (scientific name: Bombyx mori) is an insect of the order Lepidoptera. It is the main source of silk and plays an important role in human economic life and cultural history. It is native to China and is commonly known as silkworm or nymph in southern China and Taiwan.

The silkworm is called "silkworm" in English because it uses silk to make cocoons. A cocoon is made from a strand of silk that is 300-900 meters long. Today, my country's silk production and exports account for more than 70% of the world's total, and it has become a major silk country that can dominate the world's silk price trend.

4. What is the growth period of silkworms?

The growth cycle of silkworms is generally about 40 days, which is related to humidity, temperature and food. The incubation period of silkworm eggs is about 8-9 days (if accelerated, it is about 2-9 days), the larval stage is about 25 days, the pupa stage is about 14-18 days, and the moth stage is about 3-5 days.

How many days is the growth cycle of a silkworm?

1. Hatching of silkworm eggs: After an 8-9 day accelerator period, the silkworms hatch from the eggs. They are small and black when they first come out, and are commonly known as ant silkworms.

2. First instar: The color of first instar silkworms changes from black to dark brown. They feed on mulberry leaves for 3 to 4 days and do not eat much. They will shed their skin for the first time after entering the dormant period, which lasts for 8 to 12 hours.

3. Second instar: The silkworm grows noticeably bigger and becomes lighter in color. It feeds on mulberry leaves for about 3 days and sleeps for 8 to 12 hours.

4. Third instar: The color of the silkworm body changes to light brown, the appetite begins to increase, and it enters the dormant stage after about 4 days. Silkworms from 1 to 3 instars are generally called young silkworms, and enter the adult stage after 10 to 14 hours.

5. Fourth instar: The silkworms entering the adult silkworm stage develop very quickly and their food intake increases significantly. The fourth instar usually lasts for 5 days, with a long dormancy period, generally called the long dormancy period, which can last up to 30 to 40 hours.

6. Fifth instar: The silkworms eat the most leaves during the first 7 days, accounting for more than 75% of the total leaf intake. After the 7th day, the silkworms begin to shorten and become brighter, and are called mature silkworms. They stop eating and begin to spin silk and make cocoons.

5. What is the growth and development process of silkworms?

The growth process of silkworms:

Silkworm eggs: Silkworms reproduce by eggs. A female moth can lay 400 to 500 silkworm eggs. 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 will no longer change and is called a fixed color. The outer layer of silkworm eggs is a hard eggshell, and inside is yolk and serosal membrane. The embryo in the fertilized egg continuously absorbs nutrients during the development process and gradually develops into an ant silkworm. It crawls out of the eggshell, and the eggshell becomes white or light yellow after it is empty.

Ant silkworm: When the silkworm hatches from the egg, its body is brown or black, very small, and has many fine hairs, 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 wide. After it crawls out of the egg shell, it will eat mulberry leaves after 2 to 3 hours.

Silkworms eat a lot of mulberry, so they grow very fast and their body color gradually fades. But their appetite gradually decreases or even stops eating. They spit out a small amount of silk, fix their abdomen and feet on the silkworm seat, raise their head and chest, and stop moving, as if they are asleep. This is called "sleeping". The sleeping silkworm may seem motionless on the outside, but it is preparing to shed its skin inside. After shedding its old skin, the silkworm enters a new stage of growth. It sheds its skin four times from ant silkworm to spinning silk cocoon.

Silkworm age: also known as age, which indicates the development stage of the silkworm. From the first molt to the first molt is the first age; after waking up from sleep, it enters the second age; after the second molt, it enters the third age; after the third molt, it enters the fourth age, and the fourth molt is also called the long sleep. After the long sleep, it enters the fifth age. The fifth-age silkworm grows very fast, with a body length of 6 to 7 cm and a weight of about 10,000 times the weight of the worm.

Mature silkworms: When silkworms reach the end of the fifth instar, they gradually show the characteristics of maturity: first, the feces they excrete change from hard to soft, and from dark green to leaf green; their appetite decreases, and the amount of food they eat decreases; the front digestive tract is empty, and the chest becomes transparent; 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. Such silkworms are called mature silkworms.

Cocooning: People put mature silkworms in special containers or on cocoons, and the silkworms will spin silk and make cocoons.

Cocooning can be divided into four stages:

1. The mature silkworms first spin out silk, which is attached to the cocooning device, and then spin silk to connect the surrounding cocooning branches to form a cocooning support, that is, a cocooning net. The cocooning net does not have a cocoon shape, but is just some soft and messy cocoon silk layers to serve as a cocooning support.

2. After the silkworms have woven a cocoon net, they continue to spin out messy silk circles to thicken the inner layer of the cocoon net, and then spin silk in an S-shaped pattern, beginning to form the outline of the cocoon, which is called the cocoon coat. The silk fibers of the cocoon coat are thin and brittle, arranged very irregularly, and contain a lot of sericin.

3. After the cocoon is formed, the cocoon cavity gradually becomes smaller, and the front and back ends of the silkworm body bend toward the back to form a "C" shape. The silkworm continues to spit out cocoon silk, and the spinning method changes from S shape to ∞ shape, which starts the process of cocooning.

4. When the silkworm's body is greatly reduced due to spinning a large amount of silk, the swinging speed of the head and thorax slows down and there is no definite rhythm. The silk spinning begins to appear messy, forming a loose and soft cocoon silk layer, which is called pupa lining.

Silkworm pupa: After the silkworms make 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 silkworm pupa from the lines and brown dots on the abdomen. When the silkworm just turns into a pupae, its 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.

Silkworm moth (adult): Silkworm moths are shaped like butterflies, with white scales all over their bodies, but because their two pairs of wings are small, they have lost the ability to fly. The head of the silkworm moth is spherical, with bulging compound eyes and antennae; the chest has three pairs of thoracic legs and two pairs of wings; the abdomen has no ventral legs, and the terminal body segment has evolved into external genitalia. 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, the female moth can lay fertilized eggs 3 to 4 hours after mating. The male dies after mating, and the female moth can lay about 500 eggs in one night, and then slowly dies.

The silkworm lays eggs, hatches into silkworms, turns into pupae, and then turns into moths, completing the cycle of a new generation. This is the life history of the silkworm.

6. What is the growth process of silk?

Silk is made from the silk fluid secreted by mature silkworms when they make cocoons. Silkworms are holometabolous insects that go through four completely different developmental stages in their life: egg, larva, pupa and adult.

Under suitable temperature conditions, the larval stage takes 22 to 26 days from hatching to spinning cocoons. A silkworm eats about 20 to 25 grams of mulberry leaves in its lifetime. It usually hibernates and molts four times, and its weight increases by about 10,000 times when it reaches its peak growth rate.

7. How many stages are there in the life of a silkworm? What are the characteristics of each stage?

The following introduces the morphology of silkworm eggs, silkworm pupae, silkworm moths and the growth characteristics of silkworms.

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 400-500 silkworm eggs, 1700-2000 silkworm eggs, weighing about 1 gram. The color of silkworm eggs is light yellow or yellow when they are just laid, and turns into light red bean color or red bean color after 1-2 days, and then turns into gray-green or purple after 3-4 days. It will no longer change, which is called fixed color. The outer layer of silkworm eggs is a hard eggshell, and inside is yolk and serosal membrane. The embryo in the fertilized egg continuously absorbs nutrients during the development process and gradually develops into an ant silkworm. It crawls out of the eggshell, and the eggshell becomes white or light yellow after it is empty.

Ant silkworm: When the silkworm hatches from the egg, its body is brown or reddish brown, very small, and has many fine hairs, which 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 wide. After it crawls out of the egg shell, it will eat mulberry leaves after 2 to 3 hours.

The sleeping nature of silkworms: Silkworms eat a lot of mulberry, so they grow very fast and their body color gradually fades. But their appetite gradually decreases or even completely stops eating. They spit out a small amount of silk, fix their abdomen and feet on the silkworm seat, raise their head and chest, and stop moving, as if they are asleep. This is called "sleeping". The sleeping silkworms may seem motionless on the outside, but they are preparing to shed their skin inside. After shedding the old skin, the silkworms enter a new age. From ant silkworms to spinning silk cocoons, they shed their skin four times in total. Having the sleep nature is one of the growth characteristics of silkworms. Sleep nature is a genetic trait of silkworms and is also affected by the environment. The silkworms currently raised in my country belong to the four-sleeping varieties.

Silkworm age: also known as age period, which indicates the development stage of the silkworm. From the ant silkworm 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 also called the long sleep. After the long sleep, it enters the fifth age. The fifth-age silkworm grows very fast, with a body length of 6 to 7 cm and a weight of about 10,000 times the weight of the ant silkworm.

Mature silkworms: When silkworms reach the end of the fifth instar, they gradually show the characteristics of maturity: first, the feces they excrete change from hard to soft, and from dark green to leaf green; their appetite decreases, and the amount of food they eat decreases; the front digestive tract is empty, and the chest becomes transparent; 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. Such silkworms are called mature silkworms.

Cocooning during the adult stage: People put mature silkworms in special containers or on cocoons, and the silkworms will spin silk and make cocoons.

Cocooning can be divided into four processes: 1. The mature silkworms first spit out silk, which is bonded to the cocooning device, and then spit out silk to connect the surrounding cocoon branches to form a cocooning support, that is, a cocooning net. The cocooning net does not have a cocoon shape, but is just some soft and messy cocoon silk layers to serve as a support for cocooning. 2. After the silkworms make a cocooning net, they continue to spit out messy silk circles to thicken the inner layer of the cocoon net, and then spit out silk in an S-shaped manner, and the outline of the cocoon begins to appear, which is called a cocooning coat. The silk fibers of the cocoon coat are fine and brittle, arranged very irregularly, and have a high content of sericin. 3. After the cocoon coat is formed, the cocoon cavity gradually becomes smaller, and the front and rear ends of the silkworm body bend back to form a "C" shape. The silkworm continues to spit out cocoon silk, and the spinning method changes from S shape to ∞ shape, which begins the process of forming a cocoon layer. 4. When the silkworm's body is greatly reduced due to a large amount of silk spinning, the swing speed of the head and thorax slows down, and there is no certain rhythm. The spinning begins to appear messy, forming a loose and soft cocoon silk layer, called a pupa lining.

Silkworm pupa: After the silkworms make cocoons on the cocoon nest, they will turn into pupae about 4 days later. The body of the silkworm pupa is shaped 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 silkworm pupa from the lines and brown dots on the abdomen. When the silkworm just turns into a pupae, its 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.

Silkworm moth (adult): Silkworm moths are shaped like butterflies, with white scales all over their bodies, but because their two pairs of wings are small, they have lost the ability to fly. The head of the silkworm moth is spherical, with bulging compound eyes and antennae; the chest has three pairs of thoracic legs and two pairs of wings; the abdomen has no ventral legs, and the terminal body segment has evolved into external genitalia. 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, the female moth can lay fertilized eggs 3 to 4 hours after mating. The male dies after mating, and the female moth can lay about 500 eggs in one night, and then slowly dies.

The silkworm lays eggs, hatches into silkworms, turns into pupae, and then turns into moths, completing the cycle of a new generation. This is the life history of the silkworm.