Egg: Quick Facts

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Photos and Videos

Labeled diagram of an animal egg cut in half, showing structural components including the outer shell layers, inner and outer membranes, yolk with its membrane and germinal disc, and albumen with thick and thin egg white, chalaza, and chalaziferous layer.

A variety of bird eggs.

Figure 9: Eggs of spiders are enclosed in silk sacs. (Bottom) cave orb weaver (Meta menardii) with egg sac suspended from ceiling

Cheilomenes lunata

A peacock mantis shrimp, Odontodactylus scyllarus, holds a large cluster of pink eggs with its front limbs on the sandy ocean floor in North Sulawesi, Indonesia.

Close-up of a Polyphemus moth's fuzzy abdomen as it deposits small, round eggs in clusters on a dark tree branch.

snake: hatching

female tussock moth laying eggs

Figure 9: Eggs of spiders are enclosed in silk sacs. (Top) Female wolf spider with her portable egg sac attached to spinnerets

Illustration showing different breeding specializations in anurans, including Hemiphractus with eggs on its back, Phyllomedusa eggs on a leaf, Colostethus male carrying tadpoles, aquatic eggs free-floating or attached to vegetation, Physalaemus pair with foam nest, and Gastrotheca with eggs in a pouch.

Follow the development of rice-paddy fish from fertilization to hatching in a laboratory setting

Follow a female grasshopper as its eggs are fertilized, buried underground, and hatched

Watch green sea turtles hatch from eggs and head to the ocean to avoid predators

See toads engage in amphibious amplexus and witness metamorphosis of tadpoles into toads

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Topics

7 animals that lay the most unusual eggs egg packet albumen vitelline membrane fertilizin eggshell How long do chicken eggs take to hatch?Why are robin eggs blue?Yolk isolecithal yolk

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