Is fish viviparous or oviparous?
The mode of fish reproduction can be divided into three types: oviparity, oviparity and viviparity. But most fish are oviparous, some fish are oviparous, that is, the eggs are hatched in the body, become larvae and then leave the mother, this process looks like viviparity, but strictly speaking, it is also a kind of oviparity.
1. Oviparity
It is a reproductive way for parent fish to fertilise mature eggs directly in water. In this way, the eggs laid by the parent fish are mostly unprotected. It is often swallowed by a variety of enemies, and the fertilization and development of eggs in water are greatly affected by environmental conditions, so the number of eggs laid by fish in the way of egg laying is more.
2. Oviparity
That is, the egg is fertilized in the female fish and develops in the reproductive tract. In the process of development, the nutrition needed by the embryo body, like the egg laying, is completely supplied by the yolk of the fish egg itself. This way is more evolutionary than egg laying, is not affected by the ever-changing environment, and is more conducive to the protection of offspring. For example, fish such as crucian carp and wicker.
III. Viviparity
Eggs are fertilized and developed in vivo. In the process of development, the embryo body not only depends on its own yolk to nourish itself, but also produces many wrinkles and protuberances on the yolk sac wall to combine with the mother to form a yolk sac embryo disk like the umbilical cord. through this link, nutrition can be obtained directly from the mother. This mode of reproduction, similar to that of mammals, is the most progressive because the fertilization and development of eggs are reliable and guaranteed. Such as gray star sharks and real sharks.
Conclusion: the above content is for you to sort out the introduction about whether the fish is viviparous or oviparous, hoping to help friends in need.
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Bafang Laicai can choose peat soil, rotten leaf soil and the right amount of perlite and base fertilizer, or potted with fine sand. Watering conditions should be added according to seasonal changes to keep the basin soil moist. Pay attention to temperature control in winter and shading in summer. Raise money from all sides
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Is fish seafood?
It depends on whether it is freshwater fish or marine fish. For example, carp live in fresh water and are not seafood. Grouper lives in the sea and belongs to seafood. So whether it is seafood or not, it mainly depends on the living environment. What fish doesn't belong to seafood? Carp, black fish, crucian carp
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