Embryos with gastrula stage
Shape held by collagen
Shape held by cell wall
Protist called choanoflagellates.
Prokaryotes called streptococcus bacterium.
Eukaryotes called cnidarians.
Cynobacteria called anabaena.
Unlike other animals, sponges lack tissues.
The interior surface of the sponge is lined with choanocytes that have flagella and function in nutrition and gas exchange.
Mesohyl lies within the two layers of a sponge and functions in skeleton formation and dispersal of nutrients.
Sponges have highly developed reproductive organs.
A layer of cells that form during embryogenesis.
A layer of cells that directs movement of water over feeding cell surfaces.
A layer of tissues that protects the body from invading microbes.
A layer of tissues that absorb organic molecules needed for survival.
Absorption of nutrients from the environment.
The ability to move in horizontal directions to capture pray.
The development of specialized sensory organs at front end for guidance.
The development of muscles, digestive, circulatory and nervous systems.
The ability to wave food-gathering tentacles in all directions at once.
Multiple pairs of legs.
A type of exoskeleton.
Regeneration of lost limbs.
Annelid worms and mollusks.
Butterflies and moths.
Sponges and octopus.
Radial or bilateral symmetry.
A well-defined head or no head.
Diploblastic or triploblastic embryos.
True tissues or no tissues.
4, 2, 3, 1
4, 3, 1, 2
3, 4, 1, 2
3, 4, 2, 1
4, 3, 2, 1
The deuterostome condition
Some kind of exoskeleton, or hard outer covering
The diploblastic condition
Agile, speedy, and powerful locomotion
The absence of a brain.
The absence of mesoderm.
A coelom that is not completely lined with mesoderm.
A solid body without a cavity surrounding internal organs.