CATDOLL : CATDOLL: How earthworms reproduce (how earthworms reproduce)

1. How and when do earthworms reproduce?

Earthworms can reproduce in spring, summer and autumn.

Earthworms are terrestrial invertebrates of the genus Lumbricidae in the family Lumbricidae.

The body of earthworm is segmented but not divided, the papilla is degenerate, and the body surface is covered with bristles.

Earthworms are hermaphrodites. The male reproductive organs are located at the back of the 10th and 11th segments. There are two pairs of testicular sacs, each of which contains a testis and a sperm infundibulum. They are connected to the latter pair of spermatocysts through small holes on the diaphragm. The two pairs of spermatocysts are located in the 11th and 12th segments. After sperm cells are produced in the testis, they first enter the spermatocysts for development, and then return to the testicular sacs after maturity, and are discharged from the sperm infundibulum through the vas deferens.

After the 13th segment, the two vas deferens are parallel to each other. When they reach the 18th segment, they meet with the branch and main ducts of the prostate and are discharged from the male genital opening, which is on both sides of the ventral surface of the 18th segment. The female reproductive organs include a pair of grape-shaped ovaries attached to the back of the diaphragms of the 12th and 13th segments. The mature eggs fall into the body cavity, pass through a pair of egg funnels in the 13th segment, and pass through the shorter oviducts to meet in the 14th segment, and are discharged from the female genital opening, which has only one female genital opening. In addition, there are 2 or 3 pairs of spermatocysts in the 6th to 9th segments, which are places for receiving and storing foreign sperm, and open on both sides of the intersegmental groove between the 6th and 9th segments.

Although earthworms are hermaphrodites, they still need cross-fertilization because their sex cells mature at different times. The male reproductive cells of earthworms mature first. After mating, two earthworms will mate. During mating, the accessory glands secrete mucus, which makes the ventral surfaces of both sides stick to each other, and the head ends are separated into two directions. The male genital opening is opposite to the spermatheca opening of the other body, and semen is discharged from each male genital opening and enters the spermatheca through the spermatheca opening of the other.

After exchanging sperm, the two earthworms separate. When the eggs mature, the annulus secretes a sticky substance, which solidifies outside the annulus to form a ring-shaped mucus tube (earthworm cocoon). The mature eggs are discharged from the female reproductive hole into the earthworm cocoon. When the earthworm moves backward in a wave-like manner, the earthworm cocoon gradually moves forward accordingly. When it moves to the spermatheca hole, the sperm escapes and fertilizes in the cocoon. The earthworm continues to retreat, and finally the earthworm cocoon leaves the body, with both ends closed and remaining in the soil. Each earthworm cocoon has 1 to 3 embryos, which hatch within 2 to 3 weeks. If the environment is not suitable, hatching can be delayed until the spring of the following year.

In addition, earthworms have a strong ability to repair themselves. If an earthworm is cut in the middle, the two broken parts can repair themselves and grow into a complete earthworm again.

2. Can earthworms reproduce? How?

Yes. The sperm and eggs of earthworms mature at different times, so they reproduce by cross-fertilization and mating. During mating, the front ventral surfaces of the two individuals face each other, with their heads facing in opposite directions, and they stick together with the mucus secreted by the reproductive belt. The male genital pores of each are close to the spermatic vesicle pores of the other, and the protrusions of the genital pores send semen into the spermatic vesicles of the other. After exchanging semen, the two earthworms separate.

3. How do earthworms give birth to babies?

It is hermaphroditic and cross-fertilized. During reproduction, it uses an annulus to produce egg cocoons to reproduce the next generation.

Although earthworms are hermaphrodites, they cannot mate with themselves. One of the segments of an earthworm's body is different in color from the other segments. The female reproductive organ of an earthworm is located in the 13th segment, while the male reproductive organ is located in the 10th and 11th segments. The reproductive cells stored in it mature and then exchange mature sperm cells with another earthworm to produce egg cells in the body.

4. How do earthworms reproduce? Are they viviparous or oviparous?

Oviparous.

The sperm and eggs of earthworms do not mature at the same time, so they reproduce by cross-fertilization and mating. During mating, the front ventral surfaces of the two bodies face each other, and the head ends face opposite directions. They are tightly attached to each other by the mucus secreted by the reproductive belt. The male genital openings of each earthworm are close to the spermatocyst openings of the other earthworm, and the sperm is sent into the spermatocyst of the other earthworm through the reproductive protrusions. After exchanging sperm, the two earthworms separate. When the eggs mature, the reproductive belt secretes a sticky substance, forming a mucus tube outside the reproductive belt, and the eggs are ovulated in it. When the earthworm moves backward, the spermatocyst opening moves to the mucus tube, and the sperm is discharged into the tube. The sperm and eggs are fertilized in the mucus tube, and finally the earthworms exit the mucus tube, and the tube remains in the soil, with both ends closed to form an egg cocoon. The eggs develop in the egg cocoon.

5. Can earthworms lay eggs? How do they do it?

Earthworms are warm-loving animals. Wild earthworms will burrow into the soil layer and hibernate during long droughts, severe winters, and high-temperature seasons. When raising earthworms artificially, the temperature must be adjusted so that the earthworms can grow and reproduce throughout the year. The most suitable growth temperature for red earthworms is around 25°C. Earthworms are hermaphroditic animals, but they must mate with different sexes. Sexually mature earthworms (i.e., earthworms with reproductive rings) lay eggs one week after mating. However, the frequency of egg laying has a lot to do with temperature. When the temperature is below 10°C, it takes about 35 days to lay one egg; when the temperature is between 18 and 25°C, the humidity is 30% to 50%, and the ventilation is good, generally one egg is laid every 1.5 to 4.5 days; when the temperature is as high as 35°C, the number of eggs laid decreases. The hatching of egg cocoons is also closely related to temperature. When the temperature is lower than 8℃, the egg cocoon stops hatching; at 15℃, the egg cocoon hatches the young earthworms in about 33 days, with a hatching rate of 97%, and an average of 6.8 young earthworms hatched from each egg cocoon; when the average temperature is 20℃, the young earthworms hatch in 19 days; at 32℃, they can hatch in 10 days, but the hatching rate is only 33%, and an average of 2 to 3 young earthworms hatched from each egg cocoon. During the hatching process, when the accumulated temperature of the egg cocoon reaches 220 to 260℃, the young earthworms can hatch (the accumulated temperature of the egg cocoon refers to the sum of the effective temperatures accumulated daily after deducting the invalid temperature of the egg cocoon that stops hatching below 8℃). Therefore, controlling the temperature at 18 to 25℃ is most conducive to earthworm egg laying and hatching. The young earthworms grow to sexual maturity in about 38 days, and the full reproductive period is about 60 days. The egg cocoons produced by an earthworm in a month can gradually hatch 50 to 80 small earthworms.

6. What is the reproduction method of earthworms?

Earthworms are hermaphroditic animals that undergo cross-fertilization. During reproduction, they use an annulus to produce egg cocoons to reproduce the next generation.

The male organs mainly include testes, testicular sacs, spermatocysts, male genital pores, etc.; the female organs mainly include ovaries, fallopian tubes, spermatocysts, female genital pores, etc. Although earthworms are hermaphrodites, most of them mate in heterogamous ways, and some species reproduce parthenogenetically.

7. How do earthworms reproduce?

Earthworms reproduce by being hermaphroditic, with cross-fertilization, and producing egg cocoons through the annulus during reproduction. First of all, earthworms are hermaphroditic, but they cannot mate with themselves. The male reproductive cells mature first, and after maturity, two earthworms must mate. Secondly, an earthworm can produce about 400-500 egg cocoons in its lifetime. Finally, please note that earthworms like warmth, and the optimal temperature for reproduction is 22-26℃. Growth and development will stop below 8℃.

8. How do earthworms reproduce?

Earthworms reproduce in the following ways:

Earthworms are hermaphrodites. The male reproductive organs are located at the back of the 10th and 11th segments. There are two pairs of testicular sacs, each containing a testis and a sperm infundibulum, which are connected to the pair of sperm vesicles at the back through small holes on the diaphragm. The two pairs of sperm vesicles are located in the 11th and 12th segments. After sperm cells are produced in the testis, they first enter the sperm vesicles for development, and then return to the testicular sacs after maturity, and are discharged from the sperm infundibulum through the vas deferens. The two vas deferens are parallel to each other after the 13th segment. When they reach the 18th segment, they meet with the branch and main ducts of the prostate and are discharged from the male genital pore, which is on both sides of the ventral surface of the 18th segment. The female reproductive organs have a pair of grape-shaped ovaries attached to the back of the diaphragm of the 12th and 13th segments. The mature eggs fall into the body cavity, pass through a pair of egg infundibulums in the 13th segment, and pass through the shorter oviduct to meet at the 14th segment, and are discharged from the female genital pore, which has only one female genital pore. In addition, there are 2 or 3 pairs of spermatheca in the 6th to 9th segments, which are places for receiving and storing foreign sperm. They open on both sides of the abdominal intersegmental groove between the 6th and 9th segments.

Although earthworms are hermaphrodites, they still need cross-fertilization because their sex cells mature at different times. The male reproductive cells of earthworms mature first. After mating, the two earthworms will mate. During mating, the accessory glands secrete mucus, which makes the ventral surfaces of both sides stick to each other, and the head ends are separated. The male genital pore is opposite to the spermatheca pore of the opposite sex. The semen is discharged from each male genital pore and enters the spermatheca through the spermatheca pore of the other. After exchanging semen, the two earthworms separate. When the eggs mature, the annulus secretes a viscous substance, which solidifies outside the annulus to form a ring-shaped mucus tube (earthworm cocoon). The mature eggs are discharged from the female genital pore into the earthworm cocoon. When the earthworms make a wave-like backward movement, the earthworm cocoon gradually moves forward accordingly. When it moves to the spermatheca pore, the sperm escapes and fertilizes in the cocoon. The earthworms continue to retreat, and finally the earthworm cocoon leaves the body, with both ends closed and left in the soil. Each earthworm cocoon has 1 to 3 embryos, which hatch within 2 to 3 weeks. If the environment is not suitable, hatching can be delayed until the following spring.

regeneration

The earthworm is a low-level annelid. Although it has a head, a tail, a mouth, a stomach, and an anus, its entire body is like two "tubes" with pointed ends put together. The outer layer is a ring-shaped body wall, which contains a muscle system composed of mesoderm cells. Inside the body is a digestive tract that runs through layers of diaphragms from head to tail. Between the two "tubes" is filled with body cavity fluid.

When the earthworm is cut into two parts, under suitable conditions such as temperature, pH and sterilization, the muscle tissue on the cross section will immediately contract, and part of the muscle will quickly dissolve itself to form a new cell mass. At the same time, white blood cells will gather on the cross section to form an embolism, which will quickly close the wound. The protocells located in the body cavity septum quickly migrate to the cross section and form nodular regeneration buds on the cross section together with the muscle cells that have dissolved themselves. At the same time, the cells of the digestive tract, nervous system, blood vessels and other tissues in the body will rapidly grow into the regeneration buds through a large number of mitosis. In this way, with the continuous proliferation of cells, a new head will grow on the cross section of the section that lacks the head; a tail will grow on the cross section of the section that lacks the tail. In this way, one earthworm becomes two complete earthworms.