What is the difference between viviparity and oviparity, viviparity, ovoviviparity, oviparity, how t

Ovoviviparous is a form of reproduction in which the eggs of animals are fertilized in the body and develop in the body. Although the fertilized egg develops into a new individual in the mother's body, the relationship between the embryo body and the mother's structure and physiological functions is not close. The nutrients required for embryonic development mainly depend on the absorption of the yolk of the egg itself, and the embryonic body can also exchange some substances with the mother's fallopian tubes.

This is a reproductive mode formed by the long-term adaptation of animals to the adverse environment, and the actual mother mainly plays a protective and incubating role in the embryo.

The fertilized egg of an animal develops into a new individual in the mother's body before it produces the mother's body. However, the nutrients required for its development still depend on the yolk stored by the egg itself, and there is no material exchange relationship with the mother, or it only exchanges gas with the mother in the later stage of embryonic development and has little nutritional connection. It is a situation between oviparity and viviparity.

Cone tooth sharks, star sharks, certain venomous snakes (e.g., pit vipers, sea snakes), and viviparous lizards, such as the Aphyllous Drake, are ovoviviparous.

In the process of sexual reproduction of animals, although the new individual produced is not an egg but a juvenile form, there is a yolk for embryonic nutrition in the mother's body, and the development of the embryo does not directly depend on the mother's nutrition, but only the egg develops and hatches in the mother's body, which is different from the real viviparity of mammals that obtains nutrition by contacting the tissues between the mother, so this kind of reproduction is called ovoviviparity. Pit vipers, field snails, and some fish are ovoviviparous. However, in fish, there are also other ways to develop by maternal nutrition, which is also a true form of viviparity.

For example, crucian carp fertilize, develop, and hatch in the ovaries, while larvae take in nutrients from ovarian tissues in the ovarian cavity through the body epithelium and gill foramen before opening. In addition, sharks and rays rely on yolk for their initial development, but when the yolk is exhausted, they are connected to the so-called uterus in the lower part of the fallopian tube through the yolk sac (there are many villi on the inner wall) and receive nutrients from the mother, behaving similarly to the true viviparity of mammals. In addition, in terms of in vivo fertilization, some have undergone a certain degree of development in the mother's body before laying eggs (such as birds), which can also be called ovoviviparity in the generalized sense.

I'll explain it to the landlord in a colloquial way.

1. Viviparity: The development process of the fetus is completed in the mother's body.

In the process of development and growth, there is an organic bond between the fetus and the mother.

The nutrients needed by the fetus are provided by the mother;

Fetal excretion is excreted through the mother's body.

2. Ovoviviparity:

The development of the fetus is done within the mother's body.

During the development and growth of the fetus, there is no direct contact with the mother. The mother body simply provides a place for development.

3. Oviparity: The development of the fetus is completed outside the mother's body.

The above is limited to the state of nature, and human intervention does not count.

Just specifically, ovoviviparity.

Viviparity: Human, the nutrients required by the embryo are provided by the mother.

Oviparous: Chickens, the nutrients required by the embryo are provided by the yolk.

Ovoviviparous: such as snakes. After the fertilized egg is formed, it does not have an oviparous body that is excreted from the body, but develops in the fallopian tube to form an embryo and slides towards the uterus.

Nutrients for early embryonic development are also provided by the yolk, and it is not until later embryonic development that material exchange with the mother may occur. After the embryo is fully matured, the mother is delivered outside the body. Because the embryo develops from the egg and the offspring leaves the mother's body, it is called ovoviviparity.

Ovoviviparity is a type of fertility between oviparity and viviparity, in which the mother mainly provides protection and hatching for the embryo. It can be understood as an evolution that occurred in response to the harsh environment that oviparity could not cope with (eggs are eaten by other animals).

Needless to say, the difference between oviparity and viviparity, the key is viviparity and ovoviviparity:

Both produce pups directly from the mother; However, the former pups develop in the mother through the placenta and the mother's nutrient and gas exchange, while the latter is in the mother's body but develops by the nutrition in the yolk of the fertilized egg, and there is almost no material exchange with the mother, which can be regarded as "pseudoviviparity".

Viviparity is to directly produce young animals, oviparity is to lay eggs, ovoviviparity is to lay eggs but lactate like platypus.