diumenge, 20 de novembre del 2011
Oviparous
Oviparous animals lay eggs, inside which the young then develop before hatching occurs. Birds, reptiles, amphibians, fish, invertebrates and even some mammals (the monotremes) all lay eggs but they're of very different size and construction. The patterns on bird eggs are produced by glands right at the last moment as the egg is laid. For terrestrial species that lay their eggs on land, a waterproof shell prevents the contents from drying out.
Ovoviviparous
Animals produce eggs, but instead of laying the eggs, the eggs develop within the mother's body.
dimarts, 15 de novembre del 2011
dimarts, 8 de novembre del 2011
diumenge, 6 de novembre del 2011
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