Why does organisms that use internal fertilization produces less offspring than the ones that use external fertilization?

Answer 1

Because internal fertilization requires a womb and placenta to protect and nourish the growing embryos - which limits the number of offspring the mother can produce. Laying eggs outside the body means the female can potentially produce many more off-spring, and thus vastly increase the chances of the species survival.

Answer 2

Why are there generally more eggs and sperm cells produce during external fertilization thean internal fertilization

Answer 3

Animal that produce through internal fertilization produce more eggs than the animals that reproduce through the external fertilization.