CATDOLL : CATDOLL: What kind of earthworm fills in the blanks

What kind of earthworm fill in the blank

What kind of earthworm fill in the blank

Curved earthworms, slender earthworms

Fill in the blanks examples are as follows:

Wriggling earthworm

Slender earthworm

Black earthworm

Terrible earthworm

What does an earthworm look like?

Basic knowledge of earthworms A. The appearance of earthworms: Earthworms are usually slender and cylindrical, with a slightly pointed head and tail. The whole body is composed of several segments. They have no bones and are covered with a thin and pigmented chitin layer. Except for the first two segments, the remaining segments are covered with bristles. Since earthworms are common animals, the specific appearance is omitted. B. The growth of earthworms: The life cycle of earthworms is from the laying of cocoons to the hatching of young earthworms, until they mature, the appearance of rings and the beginning of egg laying. Under artificial breeding conditions, the cocoons of Eisenia fetida need 14 to 28 days to hatch into young earthworms, and then grow into adults after 30 to 45 days. Adult earthworms begin to produce cocoons 5 to 10 days after mating. If the breeding conditions are suitable, mature earthworms produce one cocoon every 1.4 to 5.5 days. The average life cycle (generation interval) of each earthworm is about 70 days. The life span of earthworms is generally calculated from the hatching of young earthworms from cocoons to the natural death of earthworms. Different types of earthworms have different life spans. Earthworms living in natural conditions in the wild have a life span of only two quarters, while under better environmental conditions, their life span can be extended to more than 2-4 years; artificially cultivated earthworms can live up to 10 to 15 years. C. Physiological habits of earthworms: 1. Earthworms are adaptable to burrowing life. Because earthworms live in caves in the soil for a long time, their body morphology and structure are quite adaptable to the living environment. 2. In nature, most earthworms live within 15 to 20 cm of the upper layer of the soil, and the lower the layer, the fewer earthworms there are. 3. Earthworms like warm, humid and quiet environments. The general activity temperature of earthworms is 5℃ to 30℃, and the optimal temperature for growth and reproduction is 15℃ to 25℃. At 0℃ to 5℃, they stop growing and developing and enter a dormant state. Below 0℃ or above 40℃ often leads to death. 4. Earthworms also like to live in a quiet environment and are afraid of noise or vibration. 5. Earthworms are very sensitive to light, like darkness, and are afraid of strong light. They often avoid strong sunlight and ultraviolet rays, but are not afraid of red light and tend to be in weak light. 6. The activities of earthworms are hidden during the day and come out at night, that is, they crawl out of the ground at dusk to find food and mate, and return to the soil in the early morning. D. The feeding characteristics of earthworms: Earthworms like to eat fine, rotten, and wet feed. In addition, they rely on their skin to absorb oxygen dissolved in water, so the supply of water is particularly important. The moisture content of the feed should be about 70%. When squeezing the upper layer of feed with your hands, there should be dripping water between the fingers, and the bottom layer should be 1 to 2 cm of water. Water once in the morning and evening every day in summer, and once every 3 to 5 days in winter, and cover the feed with straw to keep warm and moist. E. The reproductive characteristics of earthworms After the earthworms mature, most of them mate with each other, and the spouses fertilize each other, that is, the sperm is transported to the other's spermatheca for temporary storage. During or after mating, mature eggs begin to be discharged from the female hole of the earthworm and fall into the cocoon formed by the annulus. The fertilization process of the earthworm is that when the embryonic cocoon containing one or more eggs passes through the spermathecae hole, the foreign semen stored in the original mating is discharged into the embryonic cocoon. The process of earthworm cocoon production begins with the secretion of the cocoon membrane and the slender mucus tube outside the annulus of the earthworm body, from ovulation to the fall of the embryonic cocoon from the front end of the earthworm body, and the cocoon is sealed at the front and back. The embryonic development process of the earthworm (i.e. the hatching of the cocoon). It includes three stages: cleavage, germ layer development, and organogenesis.