what is the difference between internal and external fertilization?

Question

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Answer 1

Internal fertilization is a form of animal fertilization of an ovum by spermatozoon within the body of an inseminated animal, whether female or hermaphroditic. This is distinct from external fertilization, where the union of the ova and spermatoza occur outside of the organism.

In mammals, internal fertilization is done through copulation, which involves the insertion of the penis into the vagina. Some other higher vertebrates animals (most reptiles, most birds, some fish) reproduce internally, but their fertilization is cloacal.

The union of spermatozoon and ovum produces a zygote, which develops into an embryo, which, in turn, continues to develop inside the parent organism. At some point, the growing egg or offspring must be expelled. There are three general ways of doing this:

Oviparous organisms, including most insects and reptiles, monotremes, and all birds lay eggs that continue to develop after being laid, and hatch later.
Viviparous organisms, including almost all mammals (such as whales, kangaroos and humans) bear their young live. The developing young spend proportionately more time within the female's reproductive tract. The young are later released to survive on their own, with varying amounts of help from the parent(s) depending on the species.
Ovoviviparous organisms, like garter snakes, and the Madagascar hissing cockroach, have eggs (with shells) that hatch as they are laid, making it look like "live birth."

External fertilization is a form of fertilization in which a sperm cell is united with an egg cell external to the body of the female. Thus, the fertilization is said to occur "externally". This is distinct from internal fertilization where the union of the egg and sperm occur inside the female after insemination through copulation.

Many aquatic animals reproduce by external fertilization, including fish, whose females spawn ova which are fertilized by the sperm that male fish secrete into the water.

In sexual reproduction, there must be some way of getting the sperm to the egg. Since sperm are designed to be motile in a watery environment, aquatic animals can make use of the water in which they live. In many aquatic animals such as coral or Hydra, eggs and sperm are simultaneously shed into the water, and the sperm swim through the water to fertilize the egg in a process known as broadcast fertilization. In many fish species, including salmon, the female will deposit unfertilized eggs in the substrate and the male will swim by and fertilize them.

Many land plants make use of external fertilization as well. For example, bees and butterflies brush against pollen when gathering nectar from flowers and spread them to another flower of the same species, pollinating that plant.

Answer 2

Internal means the egg is fertilized inside the body due to intercourse. External, well, think of fish. The female lays the clutch of eggs and the male sprays sperm over the unfertilized eggs.

Answer 3

I would imagine the fun factor....
External fertilization takes place in things like frogs and fishes--- the mother squirts out her eggs and the male sprays them with sperm. I don't know where the joy is-- must be some, or they wouldn't be bothered
I guess you already know about internal fertilization--- and most species seem to like it a lot, no matter how brief it might be in our estimation.

Answer 4

The eggs are fertilized inside, internal, and outside, external, of the body.

Answer 5

this is in fact the distinction between reproduction requiring copulation (intercourse - inner) and not (no intercourse, sperm and eggs are deposited one by one). Many fish and perchance some amphibians are exterior fertilizers, yet are especially a lot the sole vertebrates that could try this, through low performance of leaving eggs and sperm out to dry on land.