lifecycle of silkworm
Answers
An egg is the first stage of the life cycle of the silkworm. The egg is laid by a female moth which is mostly the size of small dots. A female moth lays more than 350 eggs at a time. In the springtime, the eggs hatch due to the warmth in the air. This procedure happens once in every year.
A hairy silkworm arises after the eggs crack. In this stage of silkworms, the growth happens. they feed on mulberry leaves and consume a large amount of these leaves for around 30 days before going to the next stage.
In this stage, silkworms spin a protective cocoon around itself. It is the size of a small cotton ball and is made of a single thread of silk.
The pupa stage is a motionless stage. In this stage, people kill the pupa by plunging the cocoon into boiling water and unwind the silk thread.
In this stage, the pupa changes into an adult moth. The female moth lays eggs after mating and thus the life cycle of silkworm begins again.
Extracting silk from the cocoon is known as the processing of silk. Silk is separated from the cocoon by exposing it to sunlight. After the reeling of silk is done, the process of unwinding silk from a cocoon takes place. Silk thread is then bleached. The silk fibre is then spun into silk threads.
The life cycle of silkworm consists of four stages:-
1) The first stage in its life cycle is egg. The female moth lays an egg during summer and remains in the dormant state until the spring. This allows the egg to hatch, the eggshell provides a protective covering for the embryonic development.
2)The second stage is a larval stage. It is the vegetative stage and it is commonly called a silkworm and it is host specific to the mulberry. The silkworm feed on tender mulberry leaves. The larval stage lasts for about 27 days which goes through 5 growth stages called instars (the period between moulting).
3) The third stage pupa. At this stage, it spins a protective cocoon around itself. The cocoon serves as protection for the pupa which is in shades of white, cream and yellow. The final moult takes place inside the cocoon and the larva develops into the brown and chitinous structure called the pupa. The pupa takes about 2-3 weeks to metamorphose into an adult moth.
4) Cocoon is the fourth stage in which the larva spins a silk thread to protect itself from its predators.
5) The adult stage is called the imago. It is the reproductive stage where females lay eggs. Moths can not fly and lack functional mouthparts thus, it can not take in food.