n. An egg that can be laid on land due to the presence of a fluid-filled amniotic sac (amnion) that cushions and protects the developing embryo. amniote - n. Any of a group of land-dwelling vertebrates that have an amnion during embryonic development, including reptiles, birds, and mammals. Most extant mammals give live birth, the egg being retaine [..]

Producing two different kinds of sporangia, specifically microsporangia and megasporangia. Compare with heterosporous.

n. Very small, free-floating organisms of the ocean or other aquatic systems, including phytoplankton, which produce their own nutrients through photosynthesis, or zooplankton, which get their nutrients from organisms.

n. An external, often hard, covering or integument that provides support and protection to the body.

When the sepals and petals of a flower are indistinguishable, they are referred to as tepals. Tepals are common in many groups of monocots. More info?

That portion of the interior of the Earth that lies between the crust and the core.

Term applied to a group of organisms which does not include the most recent common ancestor of those organisms; the ancestor does not possess the character shared by members of the group. More?

n. A group of islands; an expanse of water with scattered islands.

n. A large circular volcanic depression, often originating due to collapse.

The protein "shell" of a free virus particle.