Amniota

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Images

Labeled diagram of an amniotic egg showing the embryo surrounded by membranes including the amnion, chorion, yolk sac, and allantois, with albumin, amniotic fluid, yolk, and shell also identified.

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.

Diagram of the tree of life based on the three-domain system, showing Archaea, Bacteria, and Eukaryota branching into four kingdoms: Plants, Animals, Fungi, and Protista, with illustrations of representative organisms for each group.

Amniota: Media

animal group

Images

Labeled diagram of an amniotic egg showing the embryo surrounded by membranes including the amnion, chorion, yolk sac, and allantois, with albumin, amniotic fluid, yolk, and shell also identified.

Amniotic egg.

Encyclopædia Britannica, Inc.

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.

structural components of an egg

The structural components of an egg.

Encyclopædia Britannica, Inc.

Diagram of the tree of life based on the three-domain system, showing Archaea, Bacteria, and Eukaryota branching into four kingdoms: Plants, Animals, Fungi, and Protista, with illustrations of representative organisms for each group.

The three-domain classification of life-forms

The tree of life according to the three-domain system of biological classification,...

Encyclopædia Britannica, Inc.

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