CATDOLL : CATDOLL: How do earthworms reproduce?

1. How do earthworms reproduce?

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.

2. How do earthworms reproduce?

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.

3. How do earthworms reproduce?

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.

4. How do earthworms reproduce?

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. (See Figure 17)